diff --git a/.eslintrc.js b/.eslintrc.js
new file mode 100644
index 00000000..e518c29a
--- /dev/null
+++ b/.eslintrc.js
@@ -0,0 +1,253 @@
+"use strict";
+module.exports = {
+	"env": {
+		"node": true,
+		"browser": true,
+		"commonjs": true,
+		"es6": true,
+	},
+	"parserOptions": {
+		"ecmaVersion": 11,
+	},
+
+	"overrides": [
+		{
+			"files": ["test/**/*.js", "plugins/*/test/**/*.js"],
+			"env": {
+				"mocha": "true",
+			},
+			"rules": {
+				"prefer-arrow-callback": "off",
+			},
+		},
+	],
+
+	"rules": {
+		"accessor-pairs": "error",
+		"array-bracket-newline": "off",
+		"array-bracket-spacing": ["error", "never"],
+		"array-callback-return": "error",
+		"array-element-newline": "off",
+		"arrow-body-style": "error",
+		"arrow-parens": "off",
+		"arrow-spacing": ["error", { "after": true, "before": true }],
+		"block-scoped-var": "error",
+		"block-spacing": "error",
+		"brace-style": ["warn", "1tbs", { "allowSingleLine": true }],
+		"callback-return": "off",
+		"camelcase": "off",
+		"capitalized-comments": "off",
+		"class-methods-use-this": "off",
+		"comma-dangle": [
+			"error",
+			{
+				"arrays": "always-multiline",
+				"objects": "always-multiline",
+				"functions": "only-multiline",
+			},
+		],
+		"comma-spacing": "warn",
+		"comma-style": ["error", "last"],
+		"complexity": "warn",
+		"computed-property-spacing": ["error", "never"],
+		"consistent-return": "error",
+		"consistent-this": "error",
+		"curly": "warn",
+		"default-case": "error",
+		"default-case-last": "error",
+		"default-param-last": "error",
+		"dot-location": ["error", "property"],
+		"dot-notation": ["warn", { "allowKeywords": true }],
+		"eol-last": "error",
+		"eqeqeq": "warn",
+		"func-call-spacing": "error",
+		"func-name-matching": "error",
+		"func-names": "off",
+		"func-style": ["error", "declaration"],
+		"function-call-argument-newline": "off",
+		"function-paren-newline": "off",
+		"generator-star-spacing": ["error", { "before": false, "after": true }],
+		"global-require": "warn",
+		"grouped-accessor-pairs": "error",
+		"guard-for-in": "error",
+		"handle-callback-err": "error",
+		"id-blacklist": "error",
+		"id-length": "off",
+		"id-match": "error",
+		"implicit-arrow-linebreak": "error",
+		"indent": ["error", "tab", { "SwitchCase": 1 }],
+		"indent-legacy": "off",
+		"init-declarations": "off",
+		"jsx-quotes": "error",
+		"key-spacing": "error",
+		"keyword-spacing": "warn",
+		"line-comment-position": "off",
+		"linebreak-style": ["error", "unix"],
+		"lines-around-comment": "off",
+		"lines-around-directive": "off",
+		"lines-between-class-members": ["error", "always"],
+		"max-classes-per-file": "off",
+		"max-depth": "warn",
+		"max-len": ["warn", { "code": 120 }],
+		"max-lines": "off",
+		"max-lines-per-function": "off",
+		"max-nested-callbacks": "error",
+		"max-params": "off",
+		"max-statements": "off",
+		"max-statements-per-line": "off",
+		"multiline-comment-style": ["warn", "separate-lines"],
+		"multiline-ternary": "warn",
+		"new-cap": "warn",
+		"new-parens": "error",
+		"newline-after-var": "off",
+		"newline-before-return": "off",
+		"newline-per-chained-call": "off",
+		"no-alert": "error",
+		"no-array-constructor": "error",
+		"no-await-in-loop": "off",
+		"no-bitwise": "off",
+		"no-buffer-constructor": "error",
+		"no-caller": "error",
+		"no-catch-shadow": "error",
+		"no-confusing-arrow": "error",
+		"no-console": "off",
+		"no-constant-condition": ["error", { "checkLoops": false }],
+		"no-constructor-return": "error",
+		"no-continue": "off",
+		"no-div-regex": "error",
+		"no-duplicate-imports": "error",
+		"no-else-return": "warn",
+		"no-empty-function": "off",
+		"no-eq-null": "error",
+		"no-eval": "error",
+		"no-extend-native": "error",
+		"no-extra-bind": "error",
+		"no-extra-label": "error",
+		"no-extra-parens": "off",
+		"no-floating-decimal": "error",
+		"no-implicit-coercion": "error",
+		"no-implicit-globals": "error",
+		"no-implied-eval": "error",
+		"no-inline-comments": "off",
+		"no-invalid-this": "warn",
+		"no-iterator": "error",
+		"no-label-var": "error",
+		"no-lone-blocks": "error",
+		"no-lonely-if": "error",
+		"no-loop-func": "error",
+		"no-magic-numbers": "off",
+		"no-mixed-operators": "warn",
+		"no-mixed-requires": "error",
+		"no-multi-assign": "error",
+		"no-multi-spaces": "error",
+		"no-multi-str": "error",
+		"no-multiple-empty-lines": "error",
+		"no-native-reassign": "error",
+		"no-negated-condition": "off",
+		"no-negated-in-lhs": "error",
+		"no-nested-ternary": "error",
+		"no-new": "error",
+		"no-new-func": "error",
+		"no-new-object": "error",
+		"no-new-require": "error",
+		"no-new-wrappers": "error",
+		"no-octal-escape": "error",
+		"no-param-reassign": "off",
+		"no-path-concat": "error",
+		"no-plusplus": ["warn", { "allowForLoopAfterthoughts": true }],
+		"no-process-env": "error",
+		"no-process-exit": "warn",
+		"no-proto": "error",
+		"no-restricted-exports": "error",
+		"no-restricted-globals": "error",
+		"no-restricted-imports": "error",
+		"no-restricted-modules": "error",
+		"no-restricted-properties": "error",
+		"no-restricted-syntax": "error",
+		"no-return-assign": "error",
+		"no-return-await": "off",
+		"no-script-url": "error",
+		"no-self-compare": "error",
+		"no-sequences": "error",
+		"no-shadow": "warn",
+		"no-spaced-func": "error",
+		"no-sync": "error",
+		"no-tabs": ["error", { "allowIndentationTabs": true }],
+		"no-template-curly-in-string": "error",
+		"no-ternary": "off",
+		"no-throw-literal": "error",
+		"no-trailing-spaces": "error",
+		"no-undef-init": "error",
+		"no-undefined": "off",
+		"no-unmodified-loop-condition": "error",
+		"no-unneeded-ternary": "error",
+		"no-unused-expressions": "error",
+		"no-use-before-define": "warn",
+		"no-useless-backreference": "error",
+		"no-useless-call": "error",
+		"no-useless-computed-key": "error",
+		"no-useless-concat": "error",
+		"no-useless-constructor": "error",
+		"no-useless-rename": "error",
+		"no-useless-return": "error",
+		"no-var": "warn",
+		"no-void": "error",
+		"no-warning-comments": "off",
+		"no-whitespace-before-property": "error",
+		"nonblock-statement-body-position": "error",
+		"object-curly-newline": "error",
+		"object-curly-spacing": "off",
+		"object-shorthand": "off",
+		"one-var": "off",
+		"one-var-declaration-per-line": "error",
+		"operator-assignment": "off",
+		"operator-linebreak": "warn",
+		"padded-blocks": "off",
+		"padding-line-between-statements": "error",
+		"prefer-arrow-callback": "warn",
+		"prefer-const": "off",
+		"prefer-destructuring": "off",
+		"prefer-exponentiation-operator": "error",
+		"prefer-named-capture-group": "off",
+		"prefer-numeric-literals": "error",
+		"prefer-object-spread": "error",
+		"prefer-promise-reject-errors": "error",
+		"prefer-reflect": "off",
+		"prefer-regex-literals": "error",
+		"prefer-rest-params": "error",
+		"prefer-spread": "error",
+		"prefer-template": "warn",
+		"quote-props": "off",
+		"quotes": ["error", "double", { "avoidEscape": true }],
+		"radix": ["error", "always"],
+		"require-atomic-updates": "off", // XXX Not sure why this triggers on process.title = ...
+		"require-await": "off",
+		"require-jsdoc": "off",
+		"require-unicode-regexp": "off",
+		"rest-spread-spacing": ["error", "never"],
+		"semi": "error",
+		"semi-spacing": "error",
+		"semi-style": "off",
+		"sort-imports": "error",
+		"sort-keys": "off",
+		"sort-vars": "error",
+		"space-before-blocks": "warn",
+		"space-before-function-paren": "off",
+		"space-in-parens": ["error", "never"],
+		"space-infix-ops": "off",
+		"space-unary-ops": "error",
+		"spaced-comment": ["warn", "always"],
+		"strict": "error",
+		"switch-colon-spacing": "error",
+		"symbol-description": "error",
+		"template-curly-spacing": ["error", "never"],
+		"template-tag-spacing": "error",
+		"unicode-bom": ["error", "never"],
+		"valid-jsdoc": ["error", { "requireReturn": false }],
+		"vars-on-top": "warn",
+		"wrap-iife": "error",
+		"wrap-regex": "off",
+		"yield-star-spacing": "error",
+		"yoda": ["error", "never", { "exceptRange": true }],
+	},
+};
diff --git a/.travis.yml b/.travis.yml
index 89adafcb..01d17891 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,3 +11,4 @@ script:
   - npm run-script ci-cover
   - cat temp/test/integration/log.txt
   - codecov -f coverage/lcov.info
+  - npm run-script lint
diff --git a/build-mod.js b/build-mod.js
index cf6fa86e..aef57612 100644
--- a/build-mod.js
+++ b/build-mod.js
@@ -12,11 +12,11 @@ async function main() {
 	const args = yargs
 		.scriptName("build")
 		.options({
-			'clean': { describe: "Remove previous builds", type: 'boolean', default: false },
-			'build': { describe: "Build mod", type: 'boolean', default: true },
-			'pack': { describe: "Pack into zip file", type: 'boolean', default: true },
+			"clean": { describe: "Remove previous builds", type: "boolean", default: false },
+			"build": { describe: "Build mod", type: "boolean", default: true },
+			"pack": { describe: "Pack into zip file", type: "boolean", default: true },
 			"source-dir": { describe: "Path to mod source files", nargs: 1, type: "string", default: libPath },
-			'output-dir': { describe: "Path to output built mod", nargs: 1, type: 'string', default: "dist" },
+			"output-dir": { describe: "Path to output built mod", nargs: 1, type: "string", default: "dist" },
 			"bump-patch": { describe: "Increment patch number of build", type: "boolean", default: false },
 			"factorio-version": { describe: "Override factorio_version", type: "string" },
 		})
@@ -45,7 +45,7 @@ async function build(args) {
 	}
 
 	if (args.clean) {
-		let splitter = /^(.*)_(\d+\.\d+\.\d+)(\.zip)?$/
+		let splitter = /^(.*)_(\d+\.\d+\.\d+)(\.zip)?$/;
 		for (let entry of await fs.readdir(args.outputDir)) {
 			let match = splitter.exec(entry);
 			if (match) {
@@ -66,7 +66,7 @@ async function build(args) {
 		if (args.pack) {
 			let zip = new JSZip();
 			let walker = klaw(args.sourceDir)
-				.on('data', item => {
+				.on("data", item => {
 					if (item.stats.isFile()) {
 						// On Windows the path created uses backslashes as the directory sepparator
 						// but the zip file needs to use forward slashes.  We can't use the posix
@@ -76,7 +76,7 @@ async function build(args) {
 					}
 				})
 			;
-			await events.once(walker, 'end');
+			await events.once(walker, "end");
 
 			for (let pathParts of info.additional_files || []) {
 				let filePath = path.join(...pathParts);
@@ -89,7 +89,7 @@ async function build(args) {
 			let modPath = path.join(args.outputDir, `${modName}.zip`);
 			console.log(`Writing ${modPath}`);
 			let writeStream = zip.generateNodeStream().pipe(fs.createWriteStream(modPath));
-			await events.once(writeStream, 'finish');
+			await events.once(writeStream, "finish");
 
 		} else {
 			let modDir = path.join(args.outputDir, modName);
@@ -111,7 +111,7 @@ async function build(args) {
 }
 
 if (module === require.main) {
-	main().catch(err => { console.log(err) });
+	main().catch(err => { console.log(err); });
 }
 
 module.exports = {
diff --git a/clusterctl.js b/clusterctl.js
index 989f9445..b1ae99bd 100644
--- a/clusterctl.js
+++ b/clusterctl.js
@@ -2,11 +2,12 @@
  * Command line interface for controlling a Clusterio cluster
  * @module
  */
+"use strict";
 const jwt = require("jsonwebtoken");
 const fs = require("fs-extra");
 const yargs = require("yargs");
 const version = require("./package").version;
-const asTable = require("as-table").configure({delimiter: ' | '});
+const asTable = require("as-table").configure({ delimiter: " | " });
 const chalk = require("chalk");
 const events = require("events");
 
@@ -21,18 +22,20 @@ const config = require("lib/config");
  * Formats a parsed Factorio output from lib/factorio into a readable
  * colorized output using terminal escape codes that can be printed.
  *
+ * @param {Object} output - Factorio server output.
+ * @returns {string} terminal colorized message.
  * @private
  */
 function formatOutputColored(output) {
 	let time = "";
-	if (output.format === 'seconds') {
-		time = chalk.yellow(output.time.padStart(8)) + ' ';
-	} else if (output.format === 'date') {
-		time = chalk.yellow(output.time) + ' ';
+	if (output.format === "seconds") {
+		time = chalk.yellow(output.time.padStart(8)) + " ";
+	} else if (output.format === "date") {
+		time = chalk.yellow(output.time) + " ";
 	}
 
 	let info = "";
-	if (output.type === 'log') {
+	if (output.type === "log") {
 		let level = output.level;
 		if (level === "Info") {
 			level = chalk.bold.blueBright(level);
@@ -42,10 +45,10 @@ function formatOutputColored(output) {
 			level = chalk.bold.redBright(level);
 		}
 
-		info = level + ' ' + chalk.gray(output.file) + ': ';
+		info = level + " " + chalk.gray(output.file) + ": ";
 
-	} else if (output.type === 'action') {
-		info = '[' + chalk.yellow(output.action) + '] ';
+	} else if (output.type === "action") {
+		info = "[" + chalk.yellow(output.action) + "] ";
 	}
 
 	return time + info + output.message;
@@ -66,7 +69,7 @@ class Command {
 	}
 
 	async run(args, control) {
-		await this._handler.call(this, args, control);
+		await this._handler(args, control);
 	}
 }
 
@@ -76,8 +79,8 @@ class Command {
  * Resolves a string with either an instance name or an id into an integer
  * with the instance ID.
  *
- * @param client - link to master server to query instance on.
- * @param instanceName - string with name or id of instance.
+ * @param {module:lib/link.Link} client - link to master server to query instance on.
+ * @param {string} instanceName - string with name or id of instance.
  * @returns {number} instance ID.
  * @private
  */
@@ -108,8 +111,8 @@ async function resolveInstance(client, instanceName) {
  * Resolves a string with either an slave name or an id into an integer with
  * the slave ID.
  *
- * @param client - link to master server to query slave on.
- * @param slaveName - string with name or id of slave.
+ * @param {module:lib/link.Link} client - link to master server to query slave on.
+ * @param {string} slaveName - string with name or id of slave.
  * @returns {number} slave ID.
  * @private
  */
@@ -140,8 +143,8 @@ async function resolveSlave(client, slaveName) {
  * Resolves a string with either a role name or an id into an object
  * representing the role.
  *
- * @param client - link to master server to query role on.
- * @param roleName - string with name or id of role.
+ * @param {module:lib/link.Link} client - link to master server to query role on.
+ * @param {string} roleName - string with name or id of role.
  * @returns {Object} Role info.
  * @private
  */
@@ -199,10 +202,10 @@ commands.push(new Command({
 		yargs.option("id", { type: "number", nargs: 1, describe: "Slave id", default: null });
 		yargs.option("name", { type: "string", nargs: 1, describe: "Slave name", default: null });
 		yargs.option("generate-token", {
-			type: "boolean", nargs: 0, describe: "Generate authentication token", default: false
+			type: "boolean", nargs: 0, describe: "Generate authentication token", default: false,
 		});
 		yargs.option("output", {
-			type: "string", nargs: 1, describe: "Path to output config (- for stdout)", default: "config-slave.json"
+			type: "string", nargs: 1, describe: "Path to output config (- for stdout)", default: "config-slave.json",
 		});
 	}],
 	handler: async function(args, control) {
@@ -233,29 +236,29 @@ commands.push(new Command({
 	handler: async function(args, control) {
 		let response = await link.messages.listInstances.send(control);
 		console.log(asTable(response.list));
-	}
+	},
 }));
 
 commands.push(new Command({
-	definition: ['create-instance', "Create an instance", (yargs) => {
+	definition: ["create-instance", "Create an instance", (yargs) => {
 		// XXX TODO: set any specific options?
-		yargs.option('name', {
+		yargs.option("name", {
 			type: "string",
 			nargs: 1,
 			describe: "Instance name",
 			group: "Instance Config:",
 		});
-		yargs.option('id', {
+		yargs.option("id", {
 			type: "number",
 			nargs: 1,
 			describe: "Instance ID",
 			group: "Instance Config:",
 		});
-		yargs.option('base', {
+		yargs.option("base", {
 			type: "boolean",
 			nargs: 0,
 			describe: "Specify this is a base config",
-			group: "Instance Config:"
+			group: "Instance Config:",
 		});
 	}],
 	handler: async function(args, control) {
@@ -329,10 +332,10 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['assign-instance', "Assign instance to a slave", (yargs) => {
+	definition: ["assign-instance", "Assign instance to a slave", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to assign", nargs: 1, type: 'string', demandOption: true },
-			'slave': { describe: "Slave to assign to", nargs: 1, type: 'string', demandOption: true },
+			"instance": { describe: "Instance to assign", nargs: 1, type: "string", demandOption: true },
+			"slave": { describe: "Slave to assign to", nargs: 1, type: "string", demandOption: true },
 		});
 	}],
 	handler: async function(args, control) {
@@ -346,9 +349,9 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['create-save', "Create a new save on an instance", (yargs) => {
+	definition: ["create-save", "Create a new save on an instance", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to create on", nargs: 1, type: 'string', demandOption: true },
+			"instance": { describe: "Instance to create on", nargs: 1, type: "string", demandOption: true },
 		});
 	}],
 	handler: async function(args, control) {
@@ -361,9 +364,9 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['export-data', "Export item icons and locale from instance", (yargs) => {
+	definition: ["export-data", "Export item icons and locale from instance", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to export from", nargs: 1, type: 'string', demandOption: true },
+			"instance": { describe: "Instance to export from", nargs: 1, type: "string", demandOption: true },
 		});
 	}],
 	handler: async function(args, control) {
@@ -376,10 +379,10 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['start-instance', "Start instance", (yargs) => {
+	definition: ["start-instance", "Start instance", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to start", nargs: 1, type: 'string', demandOption: true },
-			'save': { describe: "Save load, defaults to latest", nargs: 1, type: 'string' },
+			"instance": { describe: "Instance to start", nargs: 1, type: "string", demandOption: true },
+			"save": { describe: "Save load, defaults to latest", nargs: 1, type: "string" },
 		});
 	}],
 	handler: async function(args, control) {
@@ -393,9 +396,9 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['stop-instance', "Stop instance", (yargs) => {
+	definition: ["stop-instance", "Stop instance", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to stop", nargs: 1, type: 'string', demandOption: true },
+			"instance": { describe: "Instance to stop", nargs: 1, type: "string", demandOption: true },
 		});
 	}],
 	handler: async function(args, control) {
@@ -408,9 +411,9 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['delete-instance', "Delete instance", (yargs) => {
+	definition: ["delete-instance", "Delete instance", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to delete", nargs: 1, type: 'string', demandOption: true },
+			"instance": { describe: "Instance to delete", nargs: 1, type: "string", demandOption: true },
 		});
 	}],
 	handler: async function(args, control) {
@@ -421,17 +424,17 @@ commands.push(new Command({
 }));
 
 commands.push(new Command({
-	definition: ['send-rcon', "Send RCON command", (yargs) => {
+	definition: ["send-rcon", "Send RCON command", (yargs) => {
 		yargs.options({
-			'instance': { describe: "Instance to sent to", nargs: 1, type: 'string', demandOption: true },
-			'command': { describe: "command to send", nargs: 1, type: 'string', demandOption: true },
+			"instance": { describe: "Instance to sent to", nargs: 1, type: "string", demandOption: true },
+			"command": { describe: "command to send", nargs: 1, type: "string", demandOption: true },
 		});
 	}],
 	handler: async function(args, control) {
 		let response = await link.messages.sendRcon.send(control, {
 			instance_id: await resolveInstance(control, args.instance),
-			command: args.command
-		})
+			command: args.command,
+		});
 
 		// Factorio includes a newline in it's response output.
 		process.stdout.write(response.result);
@@ -466,7 +469,7 @@ commands.push(new Command({
 		let response = await link.messages.createRole.send(control, {
 			name: args.name,
 			description: args.description,
-			permissions: args.permissions
+			permissions: args.permissions,
 		});
 		console.log(`Created role ID ${response.id}`);
 	},
@@ -509,7 +512,7 @@ commands.push(new Command({
 		});
 	}],
 	handler: async function(args, control) {
-		let role = await resolveRole(control, args.role)
+		let role = await resolveRole(control, args.role);
 		await link.messages.deleteRole.send(control, { id: role.id });
 	},
 }));
@@ -623,7 +626,7 @@ class Control extends link.Link {
 	// I don't like God classes, but the alternative of putting all this state
 	// into global variables is not much better.
 	constructor(connector) {
-		super('control', 'master', connector);
+		super("control", "master", connector);
 		link.attachAllMessages(this);
 	}
 
@@ -647,7 +650,7 @@ class Control extends link.Link {
 			}
 		}
 
-		await this.connector.close(1001, "Control Quit")
+		await this.connector.close(1001, "Control Quit");
 	}
 }
 
@@ -656,12 +659,12 @@ async function startControl() {
 	yargs
 		.scriptName("clusterctl")
 		.usage("$0 <command> [options]")
-		.option('config', {
+		.option("config", {
 			nargs: 1,
 			describe: "config file to get credentails from",
 			default: "config-control.json",
 			defaultDescription: "auto",
-			type: 'string',
+			type: "string",
 		})
 		.command("control-config", "Manage Control config", config.configCommand)
 		.wrap(yargs.terminalWidth())
@@ -684,7 +687,7 @@ async function startControl() {
 		await controlConfig.load(JSON.parse(await fs.readFile(args.config)));
 
 	} catch (err) {
-		if (err.code === 'ENOENT') {
+		if (err.code === "ENOENT") {
 			console.log("Config not found, initializing new config");
 			await controlConfig.init();
 
@@ -730,10 +733,10 @@ async function startControl() {
 	});
 
 	if (commands.has(commandName)) {
-		command = commands.get(commandName);
+		let command = commands.get(commandName);
 
 		try {
-			await command.run(args, control)
+			await command.run(args, control);
 
 		} catch (err) {
 			if (err instanceof errors.CommandError) {
@@ -761,7 +764,7 @@ module.exports = {
 	_Control: Control,
 
 	_commands: commands,
-}
+};
 
 
 if (module === require.main) {
diff --git a/docs/contributing.md b/docs/contributing.md
index 7deb413b..9370d70d 100644
--- a/docs/contributing.md
+++ b/docs/contributing.md
@@ -11,6 +11,7 @@ Contents
 
 - [Workflow](#workflow)
     - [Starting a Feature Branch](#starting-a-feature-branch)
+    - [Checking your code for errors](#checking-your-code-for-errors)
     - [Submitting a Pull Request](#submitting-a-pull-request)
     - [Editing your Feature Branch](#editing-your-feature-branch)
     - [Resolving Merge Conflicts](#resolving-merge-conflicts)
@@ -76,6 +77,18 @@ you've used before.  But it's nice to have its name be somewhat
 descriptive of what it implements.
 
 
+### Checking your code for errors
+
+There's automated tests and linting setup for the project.  Please do
+add tests for any code you add and run both:
+
+    npm run test
+    npm run lint
+
+To check that your changes pass the integration tests as well as the
+ESLint rules set up for the project.
+
+
 ### Submitting a Pull Request
 
 Once you've commited changes to your feature branch that you want to
@@ -183,21 +196,13 @@ are at least a few things that have been agreed upon.
 
 JavaScript and Lua code should use double quoted strings (`"string"`)
 for all strings with the only exception that strings that contain double
-quotes may use single quotes (i.e., `'String with "quotes"'`.)  For
+quotes may use single quotes (i.e., `'String with "quotes"'`).
 JavaScript template literals may also be used where appropriate.
 
-There are places in the codebase that are using `'single'` quoted
-strings.  Should you be modifying such code use double quotes on new and
-modified lines and leave the rest untouched.
-
 
 ### Indenting
 
-JavaScript code should be indented with tabs.  There are places in the
-codebase that are mixing tabs and spaces or uses only spaces for
-indents.  Should you be modifiying such code that is mixing spaces and
-tabs as indending you should update the indenting to use tabs _on the
-code you change_ while leaving the rest of the code untouched.
+JavaScript code should be indented with tabs.
 
 Lua code should be indented with 4 spaces.
 
diff --git a/docs/jsdoc.json b/docs/jsdoc.json
index 54216916..19005b30 100644
--- a/docs/jsdoc.json
+++ b/docs/jsdoc.json
@@ -16,7 +16,6 @@
             "clusterctl.js",
             "lib/",
             "plugins/",
-            "routes/",
             "routes.js"
         ],
         "excludePattern": "node_modules"
diff --git a/lib/config/classes.js b/lib/config/classes.js
index 1e3d1c39..ca369270 100644
--- a/lib/config/classes.js
+++ b/lib/config/classes.js
@@ -47,7 +47,7 @@ class InvalidField extends Error { };
 function splitOn(separator, string) {
 	let index = string.indexOf(separator);
 	if (index === -1) {
-		return [string, ''];
+		return [string, ""];
 	}
 	return [string.slice(0, index), string.slice(index + separator.length)];
 }
@@ -73,7 +73,7 @@ class Config extends events.EventEmitter {
 		super();
 
 		if (!this.constructor._finalized) {
-			throw new Error(`Cannot instantiate incomplete Config class ${this.constructor.name}`)
+			throw new Error(`Cannot instantiate incomplete Config class ${this.constructor.name}`);
 		}
 
 		this._groups = new Map();
@@ -120,6 +120,8 @@ class Config extends events.EventEmitter {
 
 	/**
 	 * Serialize the config to a plain JavaScript object
+	 *
+	 * @returns {Object} JSON serializable representation of the config.
 	 */
 	serialize() {
 		let groups = [...this._unknownGroups.values()];
@@ -135,6 +137,9 @@ class Config extends events.EventEmitter {
 	 *
 	 * Updates all groups in the config with groups in the serialized
 	 * config passed.
+	 *
+	 * @param {Object} serializedConfig - Output from .serialize().
+	 * @param {boolean} notify - Invoke fieldChanged events if true.
 	 */
 	update(serializedConfig, notify) {
 		this._validate(serializedConfig);
@@ -150,34 +155,47 @@ class Config extends events.EventEmitter {
 
 	/**
 	 * Get the value for a config field
+	 *
+	 * @param {string} name - Name of field to get.
+	 * @returns {*} the value for the field.
 	 */
 	get(name) {
-		let [group, field] = splitOn('.', name);
+		let [group, field] = splitOn(".", name);
 		return this.group(group).get(field);
 	}
 
 	/**
 	 * Set the value for a config field
+	 *
+	 * @param {string} name - Name of field to set.
+	 * @param {*} value - the value to set on field
 	 */
 	set(name, value) {
-		let [group, field] = splitOn('.', name);
-		return this.group(group).set(field, value);
+		let [group, field] = splitOn(".", name);
+		this.group(group).set(field, value);
 	}
 
 	/**
 	 * Set property of an object value for a config field
+	 *
+	 * @param {string} name - Name of field to set property on.
+	 * @param {string} prop - Name of property to set on field.
+	 * @param {*} value - the value to set the property to.
 	 */
 	setProp(name, prop, value) {
-		let [group, field] = splitOn('.', name);
-		return this.group(group).setProp(field, prop, value);
+		let [group, field] = splitOn(".", name);
+		this.group(group).setProp(field, prop, value);
 	}
 
 	/**
 	 * Get the config group instance with the given name
+	 *
+	 * @param {string} name - Name of group to get.
+	 * @returns {module:lib/config.ConfigGroup} config group.
 	 */
 	group(name) {
 		if (!this._initialized) {
-			throw new Error(`${this.constructor.name} instance is uninitialized`)
+			throw new Error(`${this.constructor.name} instance is uninitialized`);
 		}
 		let group = this._groups.get(name);
 		if (!group) {
@@ -223,6 +241,8 @@ class Config extends events.EventEmitter {
 	 *
 	 * Adds the ConfigGroup to this config as a group that will get
 	 * initialized, loaded and serialized with this config class.
+	 *
+	 * @param {module:lib/config.ConfigGroup} group - class to register.
 	 */
 	static registerGroup(group) {
 		this._initSubclass();
@@ -261,9 +281,9 @@ class ConfigGroup {
 	 * After the creation of the new config group you have to call
 	 * either .init() or .load() on it in order to fully initialize it.
 	 */
-	constructor(serializedGroup) {
+	constructor() {
 		if (!this.constructor._finalized) {
-			throw new Error(`Cannot instantiate incomplete ConfigGroup class ${this.constructor.name}`)
+			throw new Error(`Cannot instantiate incomplete ConfigGroup class ${this.constructor.name}`);
 		}
 
 		this._fields = new Map();
@@ -276,6 +296,8 @@ class ConfigGroup {
 	 *
 	 * Computes and assigns the initial values for all fields of the
 	 * config group.
+	 *
+	 * @param {module:lib/config.Config} config - Config group belongs to.
 	 */
 	async init(config) {
 		this._config = config;
@@ -287,7 +309,7 @@ class ConfigGroup {
 
 			let value = null;
 			if (typeof def.initial_value === "function") {
-				value = await def.initial_value()
+				value = await def.initial_value();
 
 			} else if (def.initial_value !== undefined) {
 				value = def.initial_value;
@@ -303,6 +325,10 @@ class ConfigGroup {
 	 * Loads all the values from the passed serialized version of the
 	 * group and then initializes any possible missing fields from it to
 	 * their default values.
+	 *
+	 * @param {module:lib/config.Config} config - Config group belongs to.
+	 * @param {Object} serializedGroup -
+	 *     Result from a previous call to .serialize().
 	 */
 	async load(config, serializedGroup) {
 		this.update(serializedGroup, false);
@@ -320,6 +346,9 @@ class ConfigGroup {
 
 	/**
 	 * Get value for field
+	 *
+	 * @param {string} name - Name of field to get.
+	 * @returns {*} Value stored for the field.
 	 */
 	get(name) {
 		if (!this.constructor._definitions.has(name)) {
@@ -335,6 +364,8 @@ class ConfigGroup {
 	 * The field must be defined for the config group and the value is
 	 * type checked against the field definition.
 	 *
+	 * @param {string} name - Name of field to set.
+	 * @param {*} value - Value to set for field.
 	 * @throws {module:lib/config.InvalidField} if field is not defined.
 	 * @throws {module:lib/config.InvalidValue} if value is not allowed for the field.
 	 */
@@ -350,7 +381,7 @@ class ConfigGroup {
 		}
 
 		if (def.enum && !def.enum.includes(value)) {
-			throw new InvalidValue(`Expected one of [${def.enum.join(', ')}], not ${value}`);
+			throw new InvalidValue(`Expected one of [${def.enum.join(", ")}], not ${value}`);
 		}
 
 		if (basicType(value) === "string") {
@@ -364,24 +395,22 @@ class ConfigGroup {
 					value = Number.parseFloat(value);
 				}
 
-			} else if (def.type === "object" ) {
+			} else if (def.type === "object") {
 				try {
 					value = JSON.parse(value);
 				} catch (err) {
-					throw new InvalidValue(`Error parsing value for ${name}: ${err.message}`)
+					throw new InvalidValue(`Error parsing value for ${name}: ${err.message}`);
 				}
 			}
 		}
 
 		if (value === null) {
 			if (!def.optional) {
-				throw new InvalidValue(`Field ${name} cannot be null`)
+				throw new InvalidValue(`Field ${name} cannot be null`);
 			}
 
-		} else {
-			if (basicType(value) !== def.type) {
-				throw new InvalidValue(`Expected type of ${name} to be ${def.type}, not ${basicType(value)}`);
-			}
+		} else if (basicType(value) !== def.type) {
+			throw new InvalidValue(`Expected type of ${name} to be ${def.type}, not ${basicType(value)}`);
 		}
 
 		let prev = this._fields.get(name);
@@ -397,6 +426,9 @@ class ConfigGroup {
 	 * Update value of stored object field by setting the specified property
 	 * on it.  The field must be defined as an object for the config group.
 	 *
+	 * @param {string} name - Name of field to set property on.
+	 * @param {string} prop - Name of property to set on field.
+	 * @param {*} value - the value to set the property to.
 	 * @throws {module:lib/config.InvalidField} if field is not defined.
 	 * @throws {module:lib/config.InvalidValue} if field is not an object.
 	 */
@@ -430,6 +462,10 @@ class ConfigGroup {
 	 *
 	 * Overwrites the values of all the fields in this config group that
 	 * has a valid value in the passed serialized group with that value.
+	 *
+	 * @param {Object} serializedGroup -
+	 *     Result from a previous call to .serialize().
+	 * @param {boolean} notify - Invoke fieldChanged events if true.
 	 */
 	update(serializedGroup, notify) {
 		if (basicType(serializedGroup) !== "object") {
@@ -455,10 +491,9 @@ class ConfigGroup {
 				if (value !== null && basicType(value) !== def.type) {
 					continue;
 				}
-			} else {
-				if (basicType(value) !== def.type) {
-					continue;
-				}
+
+			} else if (basicType(value) !== def.type) {
+				continue;
 			}
 
 			if (def.enum && !def.enum.includes(value)) {
@@ -475,6 +510,8 @@ class ConfigGroup {
 
 	/**
 	 * Serialize the config to a plain JavaScript object
+	 *
+	 * @returns {Object} JSON serializable representation of the group.
 	 */
 	serialize() {
 		let fields = {};
@@ -517,34 +554,34 @@ class ConfigGroup {
 	/**
 	 * Define a new configuration field
 	 *
-	 * The following properties are supported:
-	 * - type:
+	 * @param {Object} item - Field definition.
+	 * @param {string} item.type -
 	 *     string declaring the type of the config value, supports
 	 *     boolean, string, number and object.
-	 * - name:
+	 * @param {string} item.name -
 	 *     Name of the configuration field.  Should follow the
 	 *     lower_case_underscore style.
-	 * - title:
+	 * @param {string} item.title -
 	 *     Text used to identify the config field in user interfaces.
-	 * - description:
+	 * @param {string} item.description -
 	 *     Text used to describe the config field in user interfaces.
-	 * - enum (optional):
+	 * @param {Array=} item.enum -
 	 *     Array of all values that are acceptible.  Useful for making
 	 *     enumerated values.
-	 * - optional (optional):
+	 * @param {boolean=} item.optional -
 	 *     True if this field can be set to null.  Defaults to false.
-	 * - initial_value (optional):
+	 * @param {*=} item.initial_value -
 	 *     Value this config field should take in a newly initialized
 	 *     config.  This can also be an async function returning the
 	 *     value to use.
 	 */
 	static define(item) {
 		if (this._finalized) {
-			throw new Error(`Cannot define field for ConfigGroup class ${this.name} after it has been finalized`)
+			throw new Error(`Cannot define field for ConfigGroup class ${this.name} after it has been finalized`);
 		}
 
 		if (basicType(this.groupName) !== "string") {
-			throw new Error(`Expected ConfigGroup class ${this.name} to have the groupName property set to a string`)
+			throw new Error(`Expected ConfigGroup class ${this.name} to have the groupName property set to a string`);
 		}
 
 		this._initSubclass();
@@ -556,7 +593,7 @@ class ConfigGroup {
 			if (!itemKeys.includes(prop)) {
 				throw new Error(`${prop} is required when defining an field`);
 			}
-		})
+		});
 
 		// Validate properties
 		let validTypes = ["boolean", "string", "number", "object"];
@@ -615,10 +652,11 @@ class ConfigGroup {
 			throw new Error(`Config field ${item.name} has already been defined`);
 		}
 
-		let computed = Object.assign({
+		let computed = {
 			optional: false,
 			fullName: `${this.groupName}.${item.name}`,
-		}, item)
+			...item,
+		};
 
 		if (!computed.optional && computed.initial_value === undefined) {
 			throw new Error(`Non-optional field ${item.name} needs an initial_value`);
@@ -632,7 +670,7 @@ class ConfigGroup {
 	 */
 	static finalize() {
 		if (basicType(this.groupName) !== "string") {
-			throw new Error(`Expected ConfigGroup class ${this.name} to have the groupName property set to a string`)
+			throw new Error(`Expected ConfigGroup class ${this.name} to have the groupName property set to a string`);
 		}
 
 		this._initSubclass();
@@ -672,4 +710,4 @@ module.exports = {
 	Config,
 	ConfigGroup,
 	PluginConfigGroup,
-}
+};
diff --git a/lib/config/definitions.js b/lib/config/definitions.js
index 212c6813..02f2ee6d 100644
--- a/lib/config/definitions.js
+++ b/lib/config/definitions.js
@@ -15,7 +15,7 @@ const classes = require("./classes");
  * @memberof module:lib/config
  */
 class MasterGroup extends classes.ConfigGroup { }
-MasterGroup.groupName = "master"
+MasterGroup.groupName = "master";
 MasterGroup.define({
 	name: "database_directory",
 	title: "Database directory",
@@ -28,7 +28,7 @@ MasterGroup.define({
 	title: "HTTP Port",
 	description: "Port to listen for HTTP connections on, set to null to not listen for HTTP connections.",
 	type: "number",
-	optional: true
+	optional: true,
 });
 MasterGroup.define({
 	name: "https_port",
@@ -139,7 +139,7 @@ SlaveGroup.define({
 	name: "factorio_directory",
 	description: "Path to directory to look for factorio installs",
 	type: "string",
-	initial_value: "factorio"
+	initial_value: "factorio",
 });
 SlaveGroup.define({
 	name: "instances_directory",
@@ -189,7 +189,7 @@ SlaveConfig.registerGroup(SlaveGroup);
  * @memberof module:lib/config
  */
 class InstanceGroup extends classes.ConfigGroup { }
-InstanceGroup.groupName = "instance"
+InstanceGroup.groupName = "instance";
 InstanceGroup.define({
 	name: "name",
 	type: "string",
@@ -314,6 +314,7 @@ function validateGroup(pluginInfo, groupName) {
 /**
  * Registers the config groups for the provided plugin infos
  *
+ * @param {Array<Object>} pluginInfos - Array of plugin info objects.
  * @memberof module:lib/config
  */
 function registerPluginConfigGroups(pluginInfos) {
@@ -362,6 +363,7 @@ function finalizeConfigs() {
  * Can be passed to yargs.command to implement a config command.  Use
  * handleConfigCommand to do the requested action.
  *
+ * @param {Object} yargs - yargs command builder.
  * @memberof module:lib/config
  */
 function configCommand(yargs) {
@@ -379,6 +381,9 @@ function configCommand(yargs) {
  *
  * Handle the actions that are made available by configCommand.
  *
+ * @param {Object} args - yargs args object.
+ * @param {module:lib/config.Config} instance - Config instance.
+ * @param {string} configPath - Path to configuration file.
  * @memberof module:lib/config
  */
 async function handleConfigCommand(args, instance, configPath) {
@@ -438,4 +443,4 @@ module.exports = {
 	finalizeConfigs,
 	configCommand,
 	handleConfigCommand,
-}
+};
diff --git a/lib/config/index.js b/lib/config/index.js
index f591436e..fa9b93b2 100644
--- a/lib/config/index.js
+++ b/lib/config/index.js
@@ -3,7 +3,8 @@
  * @author Hornwitser
  * @module lib/config
  */
+"use strict";
 module.exports = {
 	...require("./classes"),
 	...require("./definitions"),
-}
+};
diff --git a/lib/database.js b/lib/database.js
index 85894de0..74b59853 100644
--- a/lib/database.js
+++ b/lib/database.js
@@ -21,7 +21,7 @@ const { basicType } = require("lib/helpers");
 function mapToObject(map) {
 	let obj = {};
 	for (let [key, value] of map) {
-		if (typeof key !== 'string') {
+		if (typeof key !== "string") {
 			throw new Error(
 				`Expected all keys to be string but got ${typeof key}`
 			);
@@ -105,11 +105,11 @@ async function loadJsonArrayAsMap(filePath) {
 		let map = new Map();
 		for (let element of parsed) {
 			if (basicType(element) !== "object") {
-				throw new Error(`Expected all elements to be objects`);
+				throw new Error("Expected all elements to be objects");
 			}
 
 			if (element.id === undefined) {
-				throw new Error(`Expected all elements to have an id property`);
+				throw new Error("Expected all elements to have an id property");
 			}
 
 			map.set(element.id, element);
@@ -144,7 +144,6 @@ async function saveMapAsJsonArray(filePath, map) {
 }
 
 
-
 function checkName(name) {
 	if (typeof name !== "string") {
 		throw new Error("name must be a string");
@@ -232,7 +231,7 @@ class ItemDatabase {
 		checkName(name);
 
 		if (!this._items.has(name)) {
-			return 0
+			return 0;
 		}
 
 		return this._items.get(name);
@@ -287,4 +286,4 @@ module.exports = {
 	loadJsonArrayAsMap,
 	saveMapAsJsonArray,
 	ItemDatabase,
-}
+};
diff --git a/lib/errors.js b/lib/errors.js
index 2b9a6bdd..7ec888ea 100644
--- a/lib/errors.js
+++ b/lib/errors.js
@@ -2,6 +2,7 @@
  * Errors thrown in Clusterio
  * @module
  */
+"use strict";
 
 /**
  * Thrown by commands when they fail
@@ -71,4 +72,4 @@ module.exports = {
 	StartupError,
 	EnvironmentError,
 	PluginError,
-}
+};
diff --git a/lib/factorio/export.js b/lib/factorio/export.js
index 4c2d08cb..c1ac3da5 100644
--- a/lib/factorio/export.js
+++ b/lib/factorio/export.js
@@ -21,7 +21,7 @@ const buildMod = require("../../build-mod");
  */
 async function generateExportMod(server) {
 	let dependencies = [];
-	let splitter = /^(.*)_(\d+\.\d+\.\d+)(\.zip)?$/
+	let splitter = /^(.*)_(\d+\.\d+\.\d+)(\.zip)?$/;
 	for (let entry of await fs.readdir(server.writePath("mods"))) {
 		let match = splitter.exec(entry);
 		if (match && match[1] !== "export") {
@@ -106,8 +106,11 @@ async function loadFile(server, modVersions, modPath) {
  *
  * @param {module:lib/factorio.FactorioServer} server -
  *     The server to generate the export mod for.
+ * @param {Map<string, string>} modVersions -
+ *     Mapping of mod name to versions to get icons from.
  * @param {Array<Object>} items - Array of item prototypes.
- * @return {itemSheet: Jimp, itemData: Map<string, Object>} Item spritesheet and metadata.
+ * @return {{itemSheet: Jimp, itemData: Map<string,Object>}}
+ *     Item spritesheet and metadata.
  * @memberof module:lib/factorio
  * @private
  * @inner
@@ -193,6 +196,7 @@ async function exportItems(server, modVersions, items) {
 					iconLayer.scale(realScale);
 				}
 
+				// eslint-disable-next-line no-loop-func
 				iconLayer.scan(0, 0, iconLayer.bitmap.width, iconLayer.bitmap.height, function(x, y, sidx) {
 					x += xs;
 					y += ys;
@@ -248,7 +252,7 @@ async function exportItems(server, modVersions, items) {
 
 	iconSheet.crop(0, 0, width, Math.ceil(pos / (width / size)) * size);
 
-	return {iconSheet, itemData};
+	return { iconSheet, itemData };
 }
 
 /**
@@ -259,9 +263,10 @@ async function exportItems(server, modVersions, items) {
  *
  * @param {module:lib/factorio.FactorioServer} server -
  *     The server to export the locale from.
- * @param modVersions {Map<string, string>} modVersions -
+ * @param {Map<string, string>} modVersions -
  *     Mapping of mod name to version to export locale from.
- * @param modOrder {Array<string>} modOrder - Load order of the mods.
+ * @param {Array<string>} modOrder - Load order of the mods.
+ * @param {string} languageCode - Language to export locale for.
  * @returns {Map<string, string>} merged locale information
  * @memberof module:lib/factorio
  * @private
@@ -338,7 +343,7 @@ async function exportData(server) {
 		throw new Error("No items got exported");
 	}
 
-	let {iconSheet, itemData} = await exportItems(server, modVersions, items);
+	let { iconSheet, itemData } = await exportItems(server, modVersions, items);
 	let locale = await exportLocale(server, modVersions, modOrder, "en");
 
 	// Free up the memory used by zip files loaded during the export.
diff --git a/lib/factorio/index.js b/lib/factorio/index.js
index 5faa36f6..f6104a77 100644
--- a/lib/factorio/index.js
+++ b/lib/factorio/index.js
@@ -3,8 +3,9 @@
  * @module lib/factorio
  * @author Hornwitser
  */
+"use strict";
 module.exports = {
 	...require("lib/factorio/export"),
-	...require('lib/factorio/patch'),
-	...require('lib/factorio/server'),
+	...require("lib/factorio/patch"),
+	...require("lib/factorio/server"),
 };
diff --git a/lib/factorio/patch.js b/lib/factorio/patch.js
index e7545be1..6742a21f 100644
--- a/lib/factorio/patch.js
+++ b/lib/factorio/patch.js
@@ -27,6 +27,7 @@ const knownScenarios = {
  * Returns the name of the folder that all files in the zip file is
  * contained in.  Throws an error if there are multiple such folders.
  *
+ * @param {module:jszip.JSZip} zip - Zip to search through.
  * @returns {string} name of the root folder.
  * @memberof module:lib/factorio
  * @private
@@ -44,12 +45,12 @@ function findRoot(zip) {
 		if (root === null) {
 			root = pathRoot;
 		} else if (root !== pathRoot) {
-			throw new Error(`Zip contains multiple root folders`);
+			throw new Error("Zip contains multiple root folders");
 		}
 	});
 
 	if (root === null) {
-		throw new Error(`Empty zip file`);
+		throw new Error("Empty zip file");
 	}
 
 	return root;
@@ -60,19 +61,20 @@ function findRoot(zip) {
  * Generates control.lua code for loading the Clusterio modules
  *
  * @param {Object} patchInfo - The patch info files's json content
+ * @returns {string} Generated control.lua code.
  * @memberof module:lib/factorio
  * @private
  * @inner
  */
 function generateLoader(patchInfo) {
 	let lines = [
-		'-- Auto generated scenario module loader created by Clusterio',
-		'-- Modifications to this file will be lost when loaded in Clusterio',
+		"-- Auto generated scenario module loader created by Clusterio",
+		"-- Modifications to this file will be lost when loaded in Clusterio",
 		`clusterio_patch_number = ${patchInfo.patch_number}`,
-		'',
+		"",
 		'local event_handler = require("event_handler")',
-		'',
-		'-- Scenario modules',
+		"",
+		"-- Scenario modules",
 	];
 
 	for (let moduleName of patchInfo["scenario"]["modules"]) {
@@ -80,8 +82,8 @@ function generateLoader(patchInfo) {
 	}
 
 	lines.push(...[
-		'',
-		'-- Clusterio modules',
+		"",
+		"-- Clusterio modules",
 	]);
 
 	for (let module of patchInfo["modules"]) {
@@ -97,9 +99,9 @@ function generateLoader(patchInfo) {
 	}
 
 	// End last line with a newline
-	lines.push('');
+	lines.push("");
 
-	return lines.join('\n');
+	return lines.join("\n");
 }
 
 /**
@@ -188,7 +190,7 @@ function reorderDependencies(modules) {
 
 			if (cycle.includes(module.name)) {
 				cycle.push(module.name);
-				cycle.splice(0, cycle.indexOf(module.name))
+				cycle.splice(0, cycle.indexOf(module.name));
 				throw new Error(`Module dependency loop detected: ${cycle.join(" -> ")}`);
 			}
 
@@ -251,9 +253,9 @@ async function patch(savePath, modules) {
 		let moduleInfo = {
 			"name": module.name,
 			"files": [],
-		}
+		};
 
-		let dirs = [[module.path, '']];
+		let dirs = [[module.path, ""]];
 		while (dirs.length) {
 			let [dir, relativeDir] = dirs.pop();
 			for (let entry of await fs.readdir(dir, { withFileTypes: true })) {
@@ -282,7 +284,7 @@ async function patch(savePath, modules) {
 	root.file("clusterio.json", JSON.stringify(patchInfo, null, 4));
 
 	// Write back the save
-	let stream = zip.generateNodeStream({compression: "DEFLATE"});
+	let stream = zip.generateNodeStream({ compression: "DEFLATE" });
 	let pipe = stream.pipe(fs.createWriteStream(savePath));
 	await events.once(pipe, "finish");
 }
@@ -294,4 +296,4 @@ module.exports = {
 	_findRoot: findRoot,
 	_generateLoader: generateLoader,
 	_reorderDependencies: reorderDependencies,
-}
+};
diff --git a/lib/factorio/server.js b/lib/factorio/server.js
index 30843c19..9b2a033b 100644
--- a/lib/factorio/server.js
+++ b/lib/factorio/server.js
@@ -16,6 +16,7 @@ const errors = require("lib/errors");
  * Determines the version of Factorio the datadir is pointing to by
  * reading the changelog.txt in it.
  *
+ * @param {string} changelogPath - Path to changelog.txt.
  * @memberof module:lib/factorio
  * @private
  * @inner
@@ -47,6 +48,9 @@ async function getVersion(changelogPath) {
 /**
  * Comparison function for sorting Factorio version strings
  *
+ * @param {string} a - Version to compare.
+ * @param {string} b - Version to compare.
+ * @returns {number} 1 if a < b, 0 if a = b and -1 if a > b.
  * @memberof module:lib/factorio
  * @private
  * @inner
@@ -74,6 +78,11 @@ function versionOrder(a, b) {
  * Searches the given factorio dir for an installation of Factorio of
  * the target version.
  *
+ * @param {string} factorioDir - Path to Factorio installation dir(s).
+ * @param {string} targetVersion -
+ *     Version to look for, supports the special value "latest" for the
+ *     latest version available.
+ * @returns {Array} Array with path to data dir and version found.
  * @memberof module:lib/factorio
  * @private
  * @inner
@@ -140,7 +149,7 @@ function randomDynamicPort() {
 	const start = 49152;
 	const end = 65535 + 1;
 
-	return Math.floor(Math.random() * (end - start) + start)
+	return Math.floor(Math.random() * (end - start) + start);
 }
 
 /**
@@ -157,10 +166,10 @@ function randomDynamicPort() {
  */
 async function generatePassword(length) {
 	function validChar(byte) {
-		const ranges = ['az', 'AZ', '09'];
-		return ranges.some(range =>
+		const ranges = ["az", "AZ", "09"];
+		return ranges.some(range => (
 			range.codePointAt(0) <= byte && byte <= range.codePointAt(1)
-		);
+		));
 	}
 	let randomBytesAsync = util.promisify(crypto.randomBytes);
 
@@ -206,7 +215,7 @@ class LineSplitter {
 	 */
 	constructor(callback) {
 		this._callback = callback;
-		this._partial = null
+		this._partial = null;
 	}
 
 	/**
@@ -278,12 +287,12 @@ function parseOutput(line, source) {
 	let output = {
 		source,
 		received: Date.now(),
-	}
+	};
 
 	// There are three broad categories of output from Factorio, the first kind
 	// starts with the seconds since the server started and has a format of
 	// "   0.704 message"
-	const secRegex = /^ {0,3}(\d+\.\d+) (.*)$/
+	const secRegex = /^ {0,3}(\d+\.\d+) (.*)$/;
 	let secMatch = secRegex.exec(line);
 	if (secMatch) {
 		output.format = "seconds";
@@ -293,7 +302,7 @@ function parseOutput(line, source) {
 		// A seconds output has two different kinds of formats: The first is a
 		// log level and source location and has a format of
 		// "Level File.cpp:123: message"
-		const secLogRegex = /^(\w+) (\w+\.cpp:\d+): (.*)$/
+		const secLogRegex = /^(\w+) (\w+\.cpp:\d+): (.*)$/;
 		let secLogMatch = secLogRegex.exec(secContent);
 		if (secLogMatch) {
 			output.type = "log";
@@ -310,7 +319,7 @@ function parseOutput(line, source) {
 	// The second category of output starts with a date stamp of the format
 	// "yyyy-mm-dd hh:mm:ss message"
 	} else {
-		const dateRegex = /^(\d{4}-\d\d-\d\d \d\d:\d\d:\d\d) (.*)$/
+		const dateRegex = /^(\d{4}-\d\d-\d\d \d\d:\d\d:\d\d) (.*)$/;
 		let dateMatch = dateRegex.exec(line);
 		if (dateMatch) {
 			output.format = "date";
@@ -319,7 +328,7 @@ function parseOutput(line, source) {
 
 			// A date output has two general formats.  The first is an action
 			// followed by a message and has a format of "[ACTION] message"
-			const dateActionRegex = /^\[(\w+)\] (.*)$/
+			const dateActionRegex = /^\[(\w+)\] (.*)$/;
 			let dateActionMatch = dateActionRegex.exec(dateContent);
 			if (dateActionMatch) {
 				output.type = "action";
@@ -355,29 +364,29 @@ function parseOutput(line, source) {
 const outputHeuristics = [
 	// Message indicating the RCON interface has started
 	{
-		filter: { type: 'log', message: /^Starting RCON interface/ },
+		filter: { type: "log", message: /^Starting RCON interface/ },
 		action: function(output) {
-			this._startRcon().catch((err) => { this.emit('error', err); });
+			this._startRcon().catch((err) => { this.emit("error", err); });
 		},
 	},
 
 	// Message indicating the server is done starting up
 	{
-		filter: { type: 'log', message: /^updateTick\(\d+\) changing state from\(CreatingGame\) to\(InGame\)$/ },
+		filter: { type: "log", message: /^updateTick\(\d+\) changing state from\(CreatingGame\) to\(InGame\)$/ },
 		action: function(output) {
-			this._notifyGameReady().catch((err) => { this.emit('error', err); });
-		}
+			this._notifyGameReady().catch((err) => { this.emit("error", err); });
+		},
 	},
 
 	// Message indicating the server has started an autosave
 	{
 		filter: {
-			type: 'log',
+			type: "log",
 			message: /^Saving to _autosave\d+ \((non-)?blocking\)\.$/,
 		},
 		action: function(output) {
 			let name = /^Saving to (_autosave\d+) /.exec(output.message)[1];
-			this.emit('_autosave', name);
+			this.emit("_autosave", name);
 		},
 	},
 
@@ -395,7 +404,7 @@ const outputHeuristics = [
 	// Message indicating the server has finished saving
 	{
 		filter: {
-			type: 'log',
+			type: "log",
 			message: [
 				"Saving finished",
 
@@ -404,18 +413,18 @@ const outputHeuristics = [
 			],
 		},
 		action: function(output) {
-			this.emit('_saved');
-		}
+			this.emit("_saved");
+		},
 	},
 
 	// Message indicating the server is shutting down
 	{
 		filter: {
-			type: 'generic',
-			message: /^Quitting: /
+			type: "generic",
+			message: /^Quitting: /,
 		},
 		action: function(output) {
-			this.emit('_quitting');
+			this.emit("_quitting");
 
 			// On windows the Factorio server will wait for input on the console input buffer
 			// when an error occurs.  Since we can't send input there we terminate the server
@@ -423,14 +432,14 @@ const outputHeuristics = [
 			if (process.platform === "win32" && output.message === "Quitting: multiplayer error.") {
 				this._server.kill();
 			}
-		}
+		},
 	},
 
 	// Messages that might be tha cause of an unexpected shutdown.
 	{
 		filter: {
-			type: 'log',
-			level: 'Error',
+			type: "log",
+			level: "Error",
 			message: [
 				"MultiplayerManager failed: \"Binding IPv4 socket failed: Permission denied\"",
 				"MultiplayerManager failed: Host address is already in use.",
@@ -442,8 +451,8 @@ const outputHeuristics = [
 	},
 	{
 		filter: {
-			type: 'log',
-			level: 'Error',
+			type: "log",
+			level: "Error",
 			message: [
 				"Can't bind socket: Address already in use",
 				"Can't bind socket: Permission denied",
@@ -515,22 +524,22 @@ class FactorioServer extends events.EventEmitter {
 		// Array of possible causes for an unexpected shutdown
 		this._unexpected = [];
 
-		this._stdout = new LineSplitter((line) => { this._handleOutput(line, 'stdout'); });
-		this._stderr = new LineSplitter((line) => { this._handleOutput(line, 'stderr'); });
+		this._stdout = new LineSplitter((line) => { this._handleOutput(line, "stdout"); });
+		this._stderr = new LineSplitter((line) => { this._handleOutput(line, "stderr"); });
 
 		// Track autosaving
 		this._runningAutosave = null;
 		this.on("_autosave", function(name) {
 			this.emit("autosave-start", name);
 			this._runningAutosave = name;
-		})
+		});
 
 		this.on("_saved", function() {
 			if (this._runningAutosave) {
 				this.emit("autosave-finished", this._runningAutosave);
 				this._runningAutosave = null;
 			}
-		})
+		});
 	}
 
 	_check(expectedStates) {
@@ -542,40 +551,40 @@ class FactorioServer extends events.EventEmitter {
 	}
 
 	async _handleIpc(line) {
-		let channelEnd = line.indexOf('?');
+		let channelEnd = line.indexOf("?");
 		if (channelEnd === -1) {
 			throw new Error(`Malformed IPC line "${line.toString()}"`);
 		}
 
 		let channel = line
 			.slice(6, channelEnd)
-			.toString('utf-8')
-			.replace(/\\x([0-9a-f]{2})/g, (match, p1) =>
+			.toString("utf-8")
+			.replace(/\\x([0-9a-f]{2})/g, (match, p1) => (
 				String.fromCharCode(parseInt(p1, 16))
-			)
+			))
 		;
 
-		let type = line.slice(channelEnd + 1, channelEnd + 2).toString('utf-8');
+		let type = line.slice(channelEnd + 1, channelEnd + 2).toString("utf-8");
 		let content;
-		if (type === 'j') {
-			content = JSON.parse(line.slice(channelEnd + 2).toString('utf-8'));
+		if (type === "j") {
+			content = JSON.parse(line.slice(channelEnd + 2).toString("utf-8"));
 
-		} else if (type === 'f') {
-			let fileName = line.slice(channelEnd + 2).toString('utf-8');
-			let filePath = this.writePath('script-output', fileName);
+		} else if (type === "f") {
+			let fileName = line.slice(channelEnd + 2).toString("utf-8");
+			let filePath = this.writePath("script-output", fileName);
 
 			// Prevent malicious names
 			if (/[\\/\0]/.test(fileName)) {
-				throw new Error(`Invalid IPC file name '${fileName}'`)
+				throw new Error(`Invalid IPC file name '${fileName}'`);
 			}
 
-			if (fileName.endsWith('.json')) {
-				content = JSON.parse(await fs.readFile(filePath, 'utf-8'));
+			if (fileName.endsWith(".json")) {
+				content = JSON.parse(await fs.readFile(filePath, "utf-8"));
 				await fs.unlink(filePath);
 
 			} else {
-				let format = fileName.slice(fileName.lastIndexOf('.') + 1);
-				throw new Error(`Unknown IPC file format '${format}'`)
+				let format = fileName.slice(fileName.lastIndexOf(".") + 1);
+				throw new Error(`Unknown IPC file format '${format}'`);
 			}
 
 		} else {
@@ -589,13 +598,13 @@ class FactorioServer extends events.EventEmitter {
 
 	_handleOutput(line, source) {
 		if (line.slice(0, 6).equals(Buffer.from("\f$ipc:"))) {
-			this._handleIpc(line).catch(err => this.emit('error', err));
+			this._handleIpc(line).catch(err => this.emit("error", err));
 			return;
 		}
 
 		this.emit(source, line);
 
-		let output = parseOutput(line.toString('utf-8'), source);
+		let output = parseOutput(line.toString("utf-8"), source);
 		heuristicLoop: for (let heuristic of outputHeuristics) {
 			for (let [name, expected] of Object.entries(heuristic.filter)) {
 				if (!Object.hasOwnProperty.call(output, name)) {
@@ -610,10 +619,8 @@ class FactorioServer extends events.EventEmitter {
 					if (!expected.includes(output[name])) {
 						continue heuristicLoop;
 					}
-				} else {
-					if (expected !== output[name]) {
-						continue heuristicLoop;
-					}
+				} else if (expected !== output[name]) {
+					continue heuristicLoop;
 				}
 			}
 
@@ -621,7 +628,7 @@ class FactorioServer extends events.EventEmitter {
 			heuristic.action.call(this, output);
 		}
 
-		this.emit('output', output);
+		this.emit("output", output);
 	}
 
 	async _startRcon() {
@@ -642,8 +649,8 @@ class FactorioServer extends events.EventEmitter {
 		};
 
 		this._rconClient = new rconClient.Rcon(config);
-		this._rconClient.on("error", err => { /* Ignore */ });
-		this._rconClient.on('authenticated', () => { this._rconReady = true; this.emit('rcon-ready'); });
+		this._rconClient.on("error", () => { /* Ignore */ });
+		this._rconClient.on("authenticated", () => { this._rconReady = true; this.emit("rcon-ready"); });
 		this._rconClient.on("end", () => {
 			this._rconClient = null;
 			this._rconReady = false;
@@ -685,37 +692,37 @@ class FactorioServer extends events.EventEmitter {
 	}
 
 	_attachStdio() {
-		this._server.stdout.on('data', chunk => { this._stdout.data(chunk); });
-		this._server.stdout.on('close', () => { this._stdout.end(); });
-		this._server.stderr.on('data', chunk => { this._stderr.data(chunk); });
-		this._server.stderr.on('close', () => { this._stderr.end(); });
+		this._server.stdout.on("data", chunk => { this._stdout.data(chunk); });
+		this._server.stdout.on("close", () => { this._stdout.end(); });
+		this._server.stderr.on("data", chunk => { this._stderr.data(chunk); });
+		this._server.stderr.on("close", () => { this._stderr.end(); });
 	}
 
 	_watchExit() {
-		this._server.on('exit', (code, signal) => {
+		this._server.on("exit", (code, signal) => {
 			if (this._state !== "stopping") {
 				if (this._unexpected.length === 0) {
-					if (signal === 'SIGKILL') {
-						this.emit('error', new errors.EnvironmentError(
+					if (signal === "SIGKILL") {
+						this.emit("error", new errors.EnvironmentError(
 							"Factorio server was unexpectedly killed, is the system low on memory?"
 						));
 
 					} else {
 						let msg;
 						if (code !== null) {
-							msg = `Factorio server unexpectedly shut down with code ${code}`
+							msg = `Factorio server unexpectedly shut down with code ${code}`;
 						} else {
 							msg = `Factorio server was unexpectedly shut by down by signal ${signal}`;
 						}
 
-						this.emit('error', new Error(msg));
+						this.emit("error", new Error(msg));
 					}
 
 				} else if (this._unexpected.length === 1) {
-					this.emit('error', new Error(this._unexpected[0]));
+					this.emit("error", new Error(this._unexpected[0]));
 
 				} else {
-					this.emit('error', new Error(
+					this.emit("error", new Error(
 						"Factorio server unexpectedly shut down. Possible causes:\n- "+
 						this._unexpected.join("\n- ")
 					));
@@ -737,12 +744,12 @@ class FactorioServer extends events.EventEmitter {
 
 	async _notifyGameReady() {
 		this._gameReady = true;
-		this.emit('game-ready');
+		this.emit("game-ready");
 	}
 
 	async _waitForReady() {
 		if (!this._gameReady) {
-			await events.once(this, 'game-ready');
+			await events.once(this, "game-ready");
 		}
 	}
 
@@ -761,14 +768,14 @@ class FactorioServer extends events.EventEmitter {
 
 		await this._writeConfigIni();
 		this._server = child_process.spawn(
-			this.dataPath('..', 'bin', 'x64', 'factorio'),
+			this.dataPath("..", "bin", "x64", "factorio"),
 			[
-				'--config', this.writePath('config.ini'),
-				'--create', this.writePath('saves', name),
+				"--config", this.writePath("config.ini"),
+				"--create", this.writePath("saves", name),
 			],
 			{
 				detached: true,
-				stdio: 'pipe',
+				stdio: "pipe",
 			}
 		);
 
@@ -776,7 +783,7 @@ class FactorioServer extends events.EventEmitter {
 		this._server.once("exit", () => this.emit("exit"));
 
 		try {
-			let [code, signal] = await events.once(this._server, 'exit');
+			let [code, signal] = await events.once(this._server, "exit");
 			if (code !== 0) {
 				throw new Error(`Factorio exited with status ${code}`);
 			}
@@ -799,17 +806,17 @@ class FactorioServer extends events.EventEmitter {
 
 		await this._writeConfigIni();
 		this._server = child_process.spawn(
-			this.dataPath('..', 'bin', 'x64', 'factorio'),
+			this.dataPath("..", "bin", "x64", "factorio"),
 			[
-				'--config', this.writePath('config.ini'),
-				'--start-server', this.writePath('saves', save),
-				'--port', this.gamePort,
-				'--rcon-port', this.rconPort,
-				'--rcon-password', this.rconPassword,
+				"--config", this.writePath("config.ini"),
+				"--start-server", this.writePath("saves", save),
+				"--port", this.gamePort,
+				"--rcon-port", this.rconPort,
+				"--rcon-password", this.rconPassword,
 			],
 			{
 				detached: true,
-				stdio: 'pipe',
+				stdio: "pipe",
 			}
 		);
 
@@ -832,17 +839,17 @@ class FactorioServer extends events.EventEmitter {
 
 		await this._writeConfigIni();
 		this._server = child_process.spawn(
-			this.dataPath('..', 'bin', 'x64', 'factorio'),
+			this.dataPath("..", "bin", "x64", "factorio"),
 			[
-				'--config', this.writePath('config.ini'),
-				'--start-server-load-scenario', scenario,
-				'--port', this.gamePort,
-				'--rcon-port', this.rconPort,
-				'--rcon-password', this.rconPassword,
+				"--config", this.writePath("config.ini"),
+				"--start-server-load-scenario", scenario,
+				"--port", this.gamePort,
+				"--rcon-port", this.rconPort,
+				"--rcon-password", this.rconPassword,
 			],
 			{
 				detached: true,
-				stdio: 'pipe',
+				stdio: "pipe",
 			}
 		);
 
@@ -865,13 +872,13 @@ class FactorioServer extends events.EventEmitter {
 	 * @returns {string} response from server.
 	 */
 	async sendRcon(message, expectEmpty) {
-		this._check(["running", "stopping"])
+		this._check(["running", "stopping"]);
 		if (!this._rconReady) {
-			await events.once(this, 'rcon-ready');
+			await events.once(this, "rcon-ready");
 		}
 
 		let response = await this._rconClient.send(message);
-		if (expectEmpty && response !== '') {
+		if (expectEmpty && response !== "") {
 			throw new Error(`Expected empty response but got "${response}"`);
 		}
 		return response;
@@ -923,7 +930,7 @@ class FactorioServer extends events.EventEmitter {
 			// If RCON is not yet fully connected that operation needs to
 			// complete before the RCON connection can be closed cleanly.
 			if (!this._rconReady) {
-				await events.once(this, 'rcon-ready');
+				await events.once(this, "rcon-ready");
 			}
 
 			await this._rconClient.end();
@@ -942,16 +949,16 @@ class FactorioServer extends events.EventEmitter {
 		// stop if it's stuck with an infinite lua code loop.  In either
 		// case there's no recovering from it.
 		if (process.platform !== "win32") {
-			this.on('_quitting', setAlive);
-			await events.once(this._server, 'exit');
+			this.on("_quitting", setAlive);
+			await events.once(this._server, "exit");
 
 			clearTimeout(timeoutId);
-			this.off('_quitting', setAlive);
+			this.off("_quitting", setAlive);
 
 		// On windows the process is terminated immediately, but to keep
 		// ordering wait until after the exit event here.
 		} else {
-			await events.once(this._server, 'exit');
+			await events.once(this._server, "exit");
 		}
 	}
 
@@ -981,14 +988,14 @@ class FactorioServer extends events.EventEmitter {
 		this._check(["running"]);
 
 		let check = await this.sendRcon("/sc rcon.print('disabled')");
-		if (check === 'disabled\n') {
+		if (check === "disabled\n") {
 			return false;
 		}
 
 		// Factorio will print a warning to the console and ask for the command
 		// to be runned again before disabling achievements and allowing commands.
 		check = await this.sendRcon("/sc rcon.print('disabled')");
-		if (check === 'disabled\n') {
+		if (check === "disabled\n") {
 			return true;
 		}
 
@@ -1001,6 +1008,9 @@ class FactorioServer extends events.EventEmitter {
 	 * Creates a path using path.join with the given parts that's relative to
 	 * the data directory of the Factorio server.  Not valid before init has
 	 * been called.
+	 *
+	 * @param {...string} parts - Extra parts to add to the data path.
+	 * @returns {string} Data directory path.
 	 */
 	dataPath(...parts) {
 		return path.join(this._dataDir, ...parts);
@@ -1011,6 +1021,9 @@ class FactorioServer extends events.EventEmitter {
 	 *
 	 * Creates a path using path.join with the given parts that's relative to
 	 * the write directory of the Factorio server.
+	 *
+	 * @param {...string} parts - Extra parts to add to the write path.
+	 * @returns {string} Write directory path.
 	 */
 	writePath(...parts) {
 		return path.join(this._writeDir, ...parts);
@@ -1032,7 +1045,7 @@ class FactorioServer extends events.EventEmitter {
 			path: {
 				"read-data": this.dataPath(),
 				"write-data": this.writePath(),
-			}
+			},
 		});
 		await fs.outputFile(this.writePath("config.ini"), content);
 	}
diff --git a/lib/fileOps/fileOps.js b/lib/fileOps/fileOps.js
index ed42b794..07415560 100644
--- a/lib/fileOps/fileOps.js
+++ b/lib/fileOps/fileOps.js
@@ -1,6 +1,7 @@
 /**
  * @module lib/fileOps
  */
+"use strict";
 const fs = require("fs-extra");
 const path = require("path");
 
@@ -33,4 +34,4 @@ async function getNewestFile(directory, filter = (name) => true) {
 
 module.exports = {
 	getNewestFile,
-}
+};
diff --git a/lib/fileOps/index.js b/lib/fileOps/index.js
index 5df8775d..0e9bcbe8 100644
--- a/lib/fileOps/index.js
+++ b/lib/fileOps/index.js
@@ -1,2 +1,3 @@
+"use strict";
 const fileOps = require("./fileOps");
-module.exports = fileOps;
\ No newline at end of file
+module.exports = fileOps;
diff --git a/lib/generateSSLcert.js b/lib/generateSSLcert.js
index 4fbafd1b..fee1b50b 100644
--- a/lib/generateSSLcert.js
+++ b/lib/generateSSLcert.js
@@ -1,3 +1,4 @@
+"use strict";
 const forge = require("node-forge");
 const fs = require("fs-extra");
 const util = require("util");
@@ -17,7 +18,7 @@ module.exports = async function({
 	log("Generating SSL certificate with "+bits+" bits at "+sslCertPath);
 
 	let startNs = hrtime();
-	let keypair = await util.promisify(forge.pki.rsa.generateKeyPair)({bits: bits, e: 0x10001});
+	let keypair = await util.promisify(forge.pki.rsa.generateKeyPair)({ bits: bits, e: 0x10001 });
 	log("Generated 2048bit keypair in: "+(Number(hrtime()-startNs) / 1e6)+" ms");
 
 	startNs = hrtime();
@@ -41,4 +42,4 @@ module.exports = async function({
 	await fs.outputFile(sslCertPath, forge.pki.certificateToPem(cert));
 
 	log("Generated certificate in: "+(Number(hrtime()-startNs) / 1e6)+" ms");
-}
+};
diff --git a/lib/hash.js b/lib/hash.js
index 9bb694ed..147ebb50 100644
--- a/lib/hash.js
+++ b/lib/hash.js
@@ -2,25 +2,26 @@
  * Hashing functions
  * @module
  */
-const crypto = require('crypto');
-const fs = require('fs');
+"use strict";
+const crypto = require("crypto");
+const fs = require("fs");
 
 
 /**
  * Returns a promise that resolves to the SHA1 hash of the stream given
  *
- * @param stream - Node stream of the content to hash.
+ * @param {Stream} stream - Node stream of the content to hash.
  * @returns {Promise<string>} hash of the stream.
  */
 function hashStream(stream) {
 	return new Promise(function(resolve, reject) {
-		let hasher = crypto.createHash('sha1')
-		hasher.setEncoding('hex')
-		hasher.on('finish', function() {
+		let hasher = crypto.createHash("sha1");
+		hasher.setEncoding("hex");
+		hasher.on("finish", function() {
 			resolve(hasher.read());
 		});
 
-		stream.on('error', function(error) {
+		stream.on("error", function(error) {
 			// the docs doesn't say anything about what's passed on error
 			reject(error);
 		});
@@ -42,4 +43,4 @@ function hashFile(path) {
 module.exports = {
 	hashStream,
 	hashFile,
-}
+};
diff --git a/lib/helpers.js b/lib/helpers.js
index afc1f9bf..8fa63587 100644
--- a/lib/helpers.js
+++ b/lib/helpers.js
@@ -2,6 +2,7 @@
  * Collection of small utilites that are useful in multiple places.
  * @module
  */
+"use strict";
 
 /**
  * Return a string describing the type of the value passed
@@ -9,7 +10,7 @@
  * Works the same as typeof, excpet that null and array types get their
  * own string.
  *
- * @param value - value to return the type of.
+ * @param {*} value - value to return the type of.
  * @returns {string} basic type of the value passed.
  */
 function basicType(value) {
@@ -20,4 +21,4 @@ function basicType(value) {
 
 module.exports = {
 	basicType,
-}
+};
diff --git a/lib/link/connectors.js b/lib/link/connectors.js
index 271fa326..a7997f0a 100644
--- a/lib/link/connectors.js
+++ b/lib/link/connectors.js
@@ -94,7 +94,9 @@ class WebSocketBaseConnector extends events.EventEmitter {
 	/**
 	 * Send a message over the socket
 	 *
-	 * @returns the sequence number of the message sent
+	 * @param {string} type - Message type to send.
+	 * @param {Object} data - Data to send with message.
+	 * @returns {number} the sequence number of the message sent
 	 */
 	send(type, data) {
 		if (!["handshake", "connected", "closing"].includes(this._state)) {
@@ -181,6 +183,9 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 	 *
 	 * Used in the register function in order to send the register handshake
 	 * message over the WebSocket.
+	 *
+	 * @param {string} type - Message type to send.
+	 * @param {Object} data - Data to send with message.
 	 */
 	sendHandshake(type, data) {
 		this._check(["handshake"]);
@@ -191,6 +196,9 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 	 * Close the connection with the given reason.
 	 *
 	 * Sends a close frame and disconnects the connector.
+	 *
+	 * @param {number} code - WebSocket close code.
+	 * @param {string} reason - WebSocket close reason.
 	 */
 	async close(code, reason) {
 		if (this._state === "new") {
@@ -226,7 +234,7 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 		url.pathname += "api/socket";
 
 		// Open WebSocket to master
-		console.log(`SOCKET | connecting to ${url}`)
+		console.log(`SOCKET | connecting to ${url}`);
 
 		this._socket = new WebSocket(url, {
 			// For now we do not verify TLS certificates since the default setup is
@@ -261,7 +269,7 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 		}
 
 		let delay = Math.random() * this._reconnectDelay;
-		console.log(`SOCKET | waiting ${delay.toLocaleString("en", { maximumFractionDigits: 2 })} seconds for reconnect`)
+		console.log(`SOCKET | waiting ${delay.toLocaleString("en", { maximumFractionDigits: 2 })} seconds for reconnect`);
 		this._reconnectId = setTimeout(() => {
 			this._reconnectId = null;
 			this._doConnect();
@@ -302,18 +310,6 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 			console.error("SOCKET | Error:", err);
 		});
 
-		/*
-		this._socket.on("unexpected-response", (req, res) => {
-			let data = "";
-			res.on('data', (chunk) => { data += chunk; });
-			res.on('end', () => {
-				console.error(`SOCKET | Unexpeced Response ${res.statusCode}`);
-				console.error(data);
-				this._socket.emit("error", new Error(`Unexpected Response ${res.statusCode}`));
-			});
-		});
-		*/
-
 		this._socket.on("open", () => {
 			console.log("SOCKET | Open");
 		});
@@ -356,7 +352,7 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 		}
 
 		let { seq, type, data } = message;
-		if (type == 'hello') {
+		if (type == "hello") {
 			console.log(`SOCKET | received hello from master version ${data.version}`);
 			this.emit("hello", data);
 			if (this._sessionToken) {
@@ -369,7 +365,7 @@ class WebSocketClientConnector extends WebSocketBaseConnector {
 				this.register();
 			}
 
-		} else if (type === 'ready') {
+		} else if (type === "ready") {
 			console.log("SOCKET | received ready from master");
 			this._state = "connected";
 			this._sessionToken = data.session_token;
@@ -449,10 +445,12 @@ class VirtualConnector extends events.EventEmitter {
 	/**
 	 * Send a message to the other end of the connector
 	 *
-	 * @returns the sequence number of the message sent
+	 * @param {string} type - Message type to send.
+	 * @param {Object} data - Data to send with message.
+	 * @returns {number} the sequence number of the message sent
 	 */
 	send(type, data) {
-		this.other.emit('message', { seq: this._seq, type, data });
+		this.other.emit("message", { seq: this._seq, type, data });
 		return this._seq++;
 	}
 }
diff --git a/lib/link/index.js b/lib/link/index.js
index e5c18c5f..2690e686 100644
--- a/lib/link/index.js
+++ b/lib/link/index.js
@@ -3,8 +3,9 @@
  * @module lib/link
  * @author Hornwitser
  */
+"use strict";
 module.exports = {
-	...require('lib/link/link'),
-	...require('lib/link/messages'),
-	...require('lib/link/connectors'),
+	...require("lib/link/link"),
+	...require("lib/link/messages"),
+	...require("lib/link/connectors"),
 };
diff --git a/lib/link/link.js b/lib/link/link.js
index 67d2fc37..d05cfb53 100644
--- a/lib/link/link.js
+++ b/lib/link/link.js
@@ -30,17 +30,17 @@ class Link {
 		this._validators = new Map();
 
 		// Process messages received by the connector
-		connector.on('message', payload => {
+		connector.on("message", payload => {
 			try {
 				this.processMessage(payload);
 			} catch (err) {
 				if (err instanceof errors.InvalidMessage) {
-					console.error(`Invalid message on ${this.source}-${this.target} link: ${err.message}`)
+					console.error(`Invalid message on ${this.source}-${this.target} link: ${err.message}`);
 					if (err.errors) {
 						console.error(err.errors);
 					}
 				} else {
-					this.connector.emit('error', err);
+					this.connector.emit("error", err);
 				}
 			}
 		});
@@ -72,6 +72,7 @@ class Link {
 	 * Validates and invokes the handler and/or waiters for a message that has
 	 * been received.  An unhandled message is considered to be an error.
 	 *
+	 * @param {Object} message - Message to process.
 	 * @throws {module:lib/errors.InvalidMessage}
 	 *     if validation failed, is missing, the message is invalid, or no
 	 *     handlers/waiters were invoked to handle the message.
@@ -102,6 +103,7 @@ class Link {
 	/**
 	 * Invoke the handler for this message if it exists
 	 *
+	 * @param {Object} message - Message to invoke handlers on.
 	 * @returns {Boolean} true if a handler was invoked.
 	 */
 	_processHandler(message) {
@@ -117,6 +119,7 @@ class Link {
 	/**
 	 * Invokes the waiters for this message if any
 	 *
+	 * @param {Object} message - Message to invoke waiters on.
 	 * @returns {Boolean} true if a waiter was triggered.
 	 */
 	_processWaiters(message) {
@@ -196,6 +199,9 @@ class Link {
 	 * as any properties specified in data.  For example specifying { foo:
 	 * 21 } as the data will cause it to wait until a message with the right
 	 * type and a foo property value of 21 in the data payload.
+	 *
+	 * @param {string} type - Message type to wait for.
+	 * @param {Object} data - Properties to match in the message data.
 	 */
 	async waitFor(type, data) {
 		if (!this._validators.has(type)) {
@@ -243,4 +249,4 @@ class Link {
 
 module.exports = {
 	Link,
-}
+};
diff --git a/lib/link/messages.js b/lib/link/messages.js
index c157dc7e..fd0d0876 100644
--- a/lib/link/messages.js
+++ b/lib/link/messages.js
@@ -11,8 +11,8 @@ const errors = require("lib/errors");
 class Message {
 	/**
 	 * Name of the plugin this message belongs to, or null.
-	 * @returns {?string}
-	 **/
+	 * @returns {?string} - plugin name or null if not from a plugin.
+	 */
 	get plugin() {
 		if (this._plugin === undefined) {
 			let index = this.type.indexOf(":");
@@ -67,8 +67,8 @@ class Request extends Message {
 		this.permission = permission || null;
 		this.forwardTo = forwardTo;
 
-		this.requestType = type + '_request';
-		this.responseType = type + '_response';
+		this.requestType = type + "_request";
+		this.responseType = type + "_response";
 
 		if (permission === undefined && links.includes("control-master")) {
 			throw new Error(`permission is required for ${this.type} request over control-master links`);
@@ -77,10 +77,11 @@ class Request extends Message {
 			throw new Error(`permission is not allowed on ${this.type} request as it is not over control-master link`);
 		}
 
-		if (forwardTo === 'instance') {
-			requestProperties = Object.assign(
-				{"instance_id": { type: "integer" }}, requestProperties
-			);
+		if (forwardTo === "instance") {
+			requestProperties = {
+				"instance_id": { type: "integer" },
+				...requestProperties,
+			};
 
 		} else if (forwardTo !== "master" && forwardTo !== null) {
 			throw new Error(`Invalid forwardTo value ${forwardTo}`);
@@ -122,7 +123,7 @@ class Request extends Message {
 						},
 					],
 				},
-			}
+			},
 		});
 	}
 
@@ -158,7 +159,7 @@ class Request extends Message {
 
 			// Use forwarder if handler is not present.
 			if (!handler) {
-				if (this.forwardTo === 'instance') {
+				if (this.forwardTo === "instance") {
 					handler = link.forwardRequestToInstance;
 				} else if (this.forwardTo === "master") {
 					handler = link.forwardRequestToMaster;
@@ -185,7 +186,7 @@ class Request extends Message {
 						response = {};
 					}
 
-					if (!this._responseValidator({ seq: 0, type: this.responseType, response})) {
+					if (!this._responseValidator({ seq: 0, type: this.responseType, response })) {
 						console.error(this._responseValidator.errors);
 						throw new Error(`Validation failed responding to ${this.requestType}`);
 					}
@@ -208,11 +209,13 @@ class Request extends Message {
 	 * Sends the given data over the link as the request payload and waits
 	 * for the response.
 	 *
+	 * @param {module:lib/link.Link} link - Link to send request over.
+	 * @param {Object} data - Data to send with the request.
 	 * @returns {object} response data
 	 */
 	async send(link, data = {}) {
 		// XXX validate link target/source?
-		if (!this._requestValidator({ seq: 0, type: this.requestType, data})) {
+		if (!this._requestValidator({ seq: 0, type: this.requestType, data })) {
 			console.error(this._requestValidator.errors);
 			throw new Error(`Validation failed sending ${this.requestType}`);
 		}
@@ -226,7 +229,7 @@ class Request extends Message {
 }
 
 
-let messages = {}
+let messages = {};
 
 // Connection requests
 let wsLinks = ["master-control", "control-master", "master-slave", "slave-master"];
@@ -256,8 +259,8 @@ messages.debugDumpWs = new Request({
 
 // Management requests
 messages.listSlaves = new Request({
-	type: 'list_slaves',
-	links: ['control-master'],
+	type: "list_slaves",
+	links: ["control-master"],
 	permission: "core.slave.list",
 	responseProperties: {
 		"list": {
@@ -278,8 +281,8 @@ messages.listSlaves = new Request({
 });
 
 messages.listInstances = new Request({
-	type: 'list_instances',
-	links: ['control-master'],
+	type: "list_instances",
+	links: ["control-master"],
 	permission: "core.instance.list",
 	responseProperties: {
 		"list": {
@@ -324,8 +327,8 @@ messages.createSlaveConfig = new Request({
 });
 
 messages.setInstanceOutputSubscriptions = new Request({
-	type: 'set_instance_output_subscriptions',
-	links: ['control-master'],
+	type: "set_instance_output_subscriptions",
+	links: ["control-master"],
 	permission: "core.instance.follow_log",
 	requestProperties: {
 		"instance_ids": {
@@ -336,8 +339,8 @@ messages.setInstanceOutputSubscriptions = new Request({
 });
 
 messages.createInstance = new Request({
-	type: 'create_instance',
-	links: ['control-master'],
+	type: "create_instance",
+	links: ["control-master"],
 	permission: "core.instance.create",
 	requestProperties: {
 		"serialized_config": { type: "object" },
@@ -380,8 +383,8 @@ messages.setInstanceConfigProp = new Request({
 });
 
 messages.assignInstanceCommand = new Request({
-	type: 'assign_instance_command',
-	links: ['control-master'],
+	type: "assign_instance_command",
+	links: ["control-master"],
 	permission: "core.instance.assign",
 	requestProperties: {
 		"instance_id": { type: "integer" },
@@ -390,29 +393,29 @@ messages.assignInstanceCommand = new Request({
 });
 
 messages.assignInstance = new Request({
-	type: 'assign_instance',
-	links: ['master-slave'],
+	type: "assign_instance",
+	links: ["master-slave"],
 	requestProperties: {
 		"serialized_config": { type: "object" },
 	},
-	forwardTo: 'instance',
-})
+	forwardTo: "instance",
+});
 
 messages.startInstance = new Request({
-	type: 'start_instance',
-	links: ['control-master', 'master-slave', 'slave-instance'],
+	type: "start_instance",
+	links: ["control-master", "master-slave", "slave-instance"],
 	permission: "core.instance.start",
 	requestProperties: {
 		"save": { type: ["string", "null"] },
 	},
-	forwardTo: 'instance',
+	forwardTo: "instance",
 });
 
 messages.createSave = new Request({
-	type: 'create_save',
-	links: ['control-master', 'master-slave', 'slave-instance'],
+	type: "create_save",
+	links: ["control-master", "master-slave", "slave-instance"],
 	permission: "core.instance.create_save",
-	forwardTo: 'instance',
+	forwardTo: "instance",
 });
 
 messages.exportData = new Request({
@@ -423,30 +426,30 @@ messages.exportData = new Request({
 });
 
 messages.stopInstance = new Request({
-	type: 'stop_instance',
-	links: ['control-master', 'master-slave', 'slave-instance'],
+	type: "stop_instance",
+	links: ["control-master", "master-slave", "slave-instance"],
 	permission: "core.instance.stop",
-	forwardTo: 'instance',
+	forwardTo: "instance",
 });
 
 messages.deleteInstance = new Request({
-	type: 'delete_instance',
-	links: ['control-master', 'master-slave'],
+	type: "delete_instance",
+	links: ["control-master", "master-slave"],
 	permission: "core.instance.delete",
-	forwardTo: 'instance',
+	forwardTo: "instance",
 });
 
 messages.sendRcon = new Request({
-	type: 'send_rcon',
-	links: ['control-master', 'master-slave', 'slave-instance'],
+	type: "send_rcon",
+	links: ["control-master", "master-slave", "slave-instance"],
 	permission: "core.instance.send_rcon",
-	forwardTo: 'instance',
+	forwardTo: "instance",
 	requestProperties: {
 		"command": { type: "string" },
 	},
 	responseProperties: {
 		"result": { type: "string" },
-	}
+	},
 });
 
 messages.listPermissions = new Request({
@@ -501,7 +504,7 @@ messages.createRole = new Request({
 	},
 	responseProperties: {
 		"id": { type: "integer" },
-	}
+	},
 });
 
 messages.updateRole = new Request({
@@ -583,8 +586,8 @@ messages.deleteUser = new Request({
 });
 
 messages.getMetrics = new Request({
-	type: 'statistics_exporter:get_metrics',
-	links: ['master-slave', 'slave-instance'],
+	type: "statistics_exporter:get_metrics",
+	links: ["master-slave", "slave-instance"],
 	responseProperties: {
 		"results": { type: "array" },
 	},
@@ -632,20 +635,21 @@ class Event extends Message {
 		this.forwardTo = forwardTo;
 		this.broadcastTo = broadcastTo;
 
-		if (forwardTo === 'instance') {
-			eventProperties = Object.assign(
-				{"instance_id": { type: "integer" }}, eventProperties
-			);
+		if (forwardTo === "instance") {
+			eventProperties = {
+				"instance_id": { type: "integer" },
+				...eventProperties,
+			};
 
-		} else if (forwardTo !== 'master' && forwardTo !== null) {
+		} else if (forwardTo !== "master" && forwardTo !== null) {
 			throw new Error(`Invalid forwardTo value ${forwardTo}`);
 		}
 
-		if (broadcastTo !== 'instance' && broadcastTo !== null) {
+		if (broadcastTo !== "instance" && broadcastTo !== null) {
 			throw new Error(`Invalid broadcastTo value ${broadcastTo}`);
 		}
 
-		this.eventType = type + '_event';
+		this.eventType = type + "_event";
 		this._eventValidator = schema.compile({
 			$schema: "http://json-schema.org/draft-07/schema#",
 			properties: {
@@ -685,17 +689,17 @@ class Event extends Message {
 		if (this.links.includes(`${link.target}-${link.source}`)) {
 			// Use forwarder if handler is not present.
 			if (!handler) {
-				if (this.forwardTo === 'instance') {
+				if (this.forwardTo === "instance") {
 					handler = link.forwardEventToInstance;
-				} else if (this.forwardTo === 'master') {
+				} else if (this.forwardTo === "master") {
 					handler = link.forwardEventToMaster;
 				}
 			}
 
 			if (
-				this.broadcastTo === 'instance'
+				this.broadcastTo === "instance"
 				&& [
-					'instance-slave', 'slave-master', 'control-master', 'master-slave'
+					"instance-slave", "slave-master", "control-master", "master-slave",
 				].includes(`${link.target}-${link.source}`)
 			) {
 				if (!handler) {
@@ -705,7 +709,7 @@ class Event extends Message {
 					handler = async (message, event) => {
 						await link.broadcastEventToInstance(message, event);
 						await originalHandler.call(link, message, event);
-					}
+					};
 				}
 			}
 
@@ -726,9 +730,12 @@ class Event extends Message {
 	 * Send event over the given link
 	 *
 	 * Sends the given event data over the link.
+	 *
+	 * @param {module:lib/link.Link} link - Link to send event over.
+	 * @param {Object} data - Data to send with the event.
 	 */
 	send(link, data = {}) {
-		if (!this._eventValidator({ seq: 0, type: this.eventType, data})) {
+		if (!this._eventValidator({ seq: 0, type: this.eventType, data })) {
 			console.error(this._eventValidator.errors);
 			throw new Error(`Validation failed sending ${this.eventType}`);
 		}
@@ -754,7 +761,7 @@ messages.instanceInitialized = new Event({
 		"plugins": {
 			type: "object",
 			additionalProperties: { type: "string" },
-		}
+		},
 	},
 });
 messages.instanceStarted = new Event({
@@ -765,7 +772,7 @@ messages.instanceStarted = new Event({
 	},
 });
 messages.instanceStopped = new Event({
-	type: 'instance_stopped',
+	type: "instance_stopped",
 	links: ["instance-slave", "slave-master"],
 	eventProperties: {
 		"instance_id": { type: "integer" },
@@ -773,8 +780,8 @@ messages.instanceStopped = new Event({
 });
 
 messages.updateInstances = new Event({
-	type: 'update_instances',
-	links: ['slave-master'],
+	type: "update_instances",
+	links: ["slave-master"],
 	eventProperties: {
 		"instances": {
 			type: "array",
@@ -792,9 +799,9 @@ messages.updateInstances = new Event({
 });
 
 messages.instanceOutput = new Event({
-	type: 'instance_output',
-	links: ['instance-slave', 'slave-master', 'master-control'],
-	forwardTo: 'master',
+	type: "instance_output",
+	links: ["instance-slave", "slave-master", "master-control"],
+	forwardTo: "master",
 	eventProperties: {
 		"instance_id": { type: "integer" },
 		"output": {
@@ -843,11 +850,12 @@ messages.playerEvent = new Event({
  * link instance as the concatenation of the name of the message, the
  * name of message class, and 'Handler'.
  *
+ * @param {module:lib/link.Link} link - Link to attach messages to.
  * @memberof module:lib/link
  */
 function attachAllMessages(link) {
 	for (let [name, message] of Object.entries(messages)) {
-		message.attach(link, link[name + message.constructor.name + 'Handler']);
+		message.attach(link, link[name + message.constructor.name + "Handler"]);
 	}
 }
 
@@ -860,4 +868,4 @@ module.exports = {
 	attachAllMessages,
 
 	messages,
-}
+};
diff --git a/lib/luaTools.js b/lib/luaTools.js
index 7566e03e..48ad79dd 100644
--- a/lib/luaTools.js
+++ b/lib/luaTools.js
@@ -2,9 +2,13 @@
  * Utilities for dealing with Lua
  * @module
  */
+"use strict";
 
 /**
  * Escapes a string for inclusion into a lua string
+ *
+ * @param {string} content - String to escape.
+ * @returns {string} Escaped string.
  */
 function escapeString(content) {
 	return content
@@ -19,4 +23,4 @@ function escapeString(content) {
 
 module.exports = {
 	escapeString,
-}
+};
diff --git a/lib/manager/modManager.js b/lib/manager/modManager.js
index 80e3b140..19fb28ac 100644
--- a/lib/manager/modManager.js
+++ b/lib/manager/modManager.js
@@ -1,41 +1,45 @@
+// This file will be rewritten from scratch
+/* eslint-disable */
 /**
 Provides tools to manage mods in a clusterio install
 @module
 */
 
-const asTable = require("as-table").configure({delimiter: ' | '});
+"use strict";
+const asTable = require("as-table").configure({delimiter: " | "});
 const moment = require("moment");
 const syncRequest = require("sync-request");
 const fs = require("fs-extra");
-const https = require('follow-redirects').https;
+const https = require("follow-redirects").https;
 const factorioAPI = require("node-factorio-api");
 const sLog = require("single-line-log").stdout;
-const query = require('cli-interact').getYesNo;
+const query = require("cli-interact").getYesNo;
 const path = require("path");
 
 const fileOps = require("lib/fileOps");
 
 
 function ellipse(str, max){
-   return str.length > (max - 3) ? str.substring(0,max-3) + '...' : str;
+	return str.length > (max - 3) ? str.substring(0,max-3) + "..." : str;
 }
 
 // https://stackoverflow.com/questions/15900485/correct-way-to-convert-size-in-bytes-to-kb-mb-gb-in-javascript
 function formatBytes(size, decimals) {
-	if (bytes === 0) return '0 Bytes';
+	if (bytes === 0) return "0 Bytes";
 
 	const k = 1024;
 	const dm = decimals < 0 ? 0 : decimals;
-	const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
+	const sizes = ["Bytes", "KB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"];
 
 	const i = Math.floor(Math.log(bytes) / Math.log(k));
 
-	return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
+	return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + " " + sizes[i];
 }
 
 
 /**
 Lists mods for an instance as a table. Warning, handles printing internally.
+@param {Object} config - Obsolete config
 @param {Instance} instance - Instance object, see slave.js
 
 @example
@@ -52,7 +56,7 @@ async function listMods(config, instance) {
 			factorioAPI.authenticate({
 				username: config.username,
 				token: config.token,
-				require_ownership: false
+				require_ownership: false,
 			}).then(token => {
 				console.log("* Currently installed:");
 				factorioAPI.readModZips().then(list => {
@@ -63,14 +67,14 @@ async function listMods(config, instance) {
 							date:mod.date,
 							factorio_ver:mod.factorio_version,
 							author:mod.author,
-						}
+						};
 					})));
 				});
 				// Had issues earlier due to bug in node-factorio-api, see https://github.com/Danacus/node-factorio-api/issues/2
 				// bug is resolved, thanks to @Danacus and @brotherpot
 				factorioAPI.getModsFromSaves().then(list => {
 					console.log("* Mods used in save:");
-					console.log(asTable(list[0].mods))
+					console.log(asTable(list[0].mods));
 				});
 			}).catch(reason => {
 				console.log("Failed to authenticate to factorio.com! Please check your connection and the username+token used for authentication in config.json");
@@ -78,14 +82,14 @@ async function listMods(config, instance) {
 			});
 		} else {
 			// list shared mods in /sharedMods/
-			factorioAPI.init(false, 'sharedMods/', '', instance.server.version);
+			factorioAPI.init(false, "sharedMods/", "", instance.server.version);
 			factorioAPI.authenticate({
 				username: config.username,
 				token: config.token,
-				require_ownership: false
+				require_ownership: false,
 			}).then(() => {
-				console.log("\r\n")
-				console.log("* Mods shared by all instances:")
+				console.log("\r\n");
+				console.log("* Mods shared by all instances:");
 				factorioAPI.getInstalledMods().then(mods => {
 					console.log(asTable(mods));
 					resolve();
@@ -108,6 +112,7 @@ async function listMods(config, instance) {
 Searches mods.factorio.com for mods matching a search term and prints
 the results to console as a neat looking table
 
+@param {Object} config - Obsolete config
 @param {string} searchTerm What to search for
 */
 async function findMods(config, searchTerm) {
@@ -116,7 +121,7 @@ async function findMods(config, searchTerm) {
 		factorioAPI.authenticate({
 			username: config.username,
 			token: config.token,
-			require_ownership: false
+			require_ownership: false,
 		}).then(token => {
 			factorioAPI.searchMods(searchTerm).then(mods => {
 				let result = asTable(mods.reverse().map(mod => {
@@ -128,7 +133,7 @@ async function findMods(config, searchTerm) {
 						latest_version: mod.latest_release.version,
 						owner:mod.owner,
 						//license: mod.license_name,
-					}
+					};
 				}));
 				resolve(result);
 				// console.log(result);
@@ -154,7 +159,7 @@ async function addMod(config, term, instance) {
 				factorioAPI.authenticate({
 					username: config.username,
 					token: config.token,
-					require_ownership: false
+					require_ownership: false,
 				}).then(() => {
 					factorioAPI.searchMods(term.split("/")[term.split("/").length-1]).then(body => {
 						console.log("Im gonna download: "+body[0].name + " in version: " + body[0].latest_release.version);
@@ -168,7 +173,7 @@ async function addMod(config, term, instance) {
 				// treat it as a github releases download
 				let apiURL = "https://api.github.com/repos/" + term.split("/")[3] + "/" + term.split("/")[4] + "/releases"; // https://api.github.com/repos/Danielv123/factorioClusterioMod/releases
 
-				let res = syncRequest('GET', apiURL, {"headers":{"User-Agent":"factorioClusterio"}});
+				let res = syncRequest("GET", apiURL, {"headers":{"User-Agent":"factorioClusterio"}});
 				let url = JSON.parse(res.getBody())[0].assets[0].browser_download_url;
 				let name = JSON.parse(res.getBody())[0].assets[0].name;
 				if (url) {
@@ -177,7 +182,7 @@ async function addMod(config, term, instance) {
 					let bytesDownloaded = 0;
 					let downloadStartTime = Date.now();
 					https.get(url, function(response) {
-						let bytesToDownload = response.headers['content-length'];
+						let bytesToDownload = response.headers["content-length"];
 						response.pipe(file);
 						response.on("data", chunk => {
 							bytesDownloaded += chunk.length;
@@ -188,7 +193,7 @@ async function addMod(config, term, instance) {
 							"about "+timeToComplete+" seconds remaining ("+formatBytes(bytesPerSecond)+"/s)");
 						}).on("end", x => {
 							sLog.clear();
-							console.log(" Downloaded in "+moment.utc(moment.duration(Date.now()-downloadStartTime).as('milliseconds')).format('mm:ss')); // because sLog.clear() doesn't seem to do the job of ending the line properly
+							console.log(" Downloaded in "+moment.utc(moment.duration(Date.now()-downloadStartTime).as("milliseconds")).format("mm:ss")); // because sLog.clear() doesn't seem to do the job of ending the line properly
 							resolve();
 						});
 					});
@@ -199,10 +204,10 @@ async function addMod(config, term, instance) {
 				factorioAPI.authenticate({
 					username: config.username,
 					token: config.token,
-					require_ownership: false
+					require_ownership: false,
 				}).then(() => {
 					factorioAPI.searchMods(term).then(body => {
-						console.log(body)
+						console.log(body);
 						console.log("Im gonna download: "+body[0].name + " in version: " + body[0].latest_release.version);
 						factorioAPI.downloadMod( {name: body[0].name, version: body[0].latest_release.version}).then(()=>{
 							console.log("Mod downloaded");
@@ -242,7 +247,7 @@ async function removeMod(config, term, instance, force = false) {
 						fs.unlinkSync(path.join(modDirectory, modsMatchingFilter[i]));
 						console.log("Deleted "+modsMatchingFilter[i]);
 					}
-				} else console.log("Did not delete mods.")
+				} else console.log("Did not delete mods.");
 			}
 			resolve();
 		} else {
@@ -261,10 +266,10 @@ the latest release, saving it to /sharedMods
 function downloadFromGitURL(url) {
 	console.log("Downloading mod from "+url);
 	// get JSON data about releases
-	let res = syncRequest('GET', url, {"headers":{"User-Agent":"factorioClusterio"}});
+	let res = syncRequest("GET", url, {"headers":{"User-Agent":"factorioClusterio"}});
 	let downloadUrl = JSON.parse(res.getBody())[0].assets[0].browser_download_url;
 	let name = JSON.parse(res.getBody())[0].assets[0].name;
-	console.log(JSON.parse(res.getBody()))
+	console.log(JSON.parse(res.getBody()));
 	if (downloadUrl) {
 		console.log(downloadUrl);
 		let file = fs.createWriteStream("sharedMods/"+name);
@@ -291,4 +296,4 @@ module.exports = {
 	addMod,
 	removeMod,
 	downloadFromGitURL,
-}
+};
diff --git a/lib/npmPostinstall.js b/lib/npmPostinstall.js
index ad3cbe83..cc23a327 100644
--- a/lib/npmPostinstall.js
+++ b/lib/npmPostinstall.js
@@ -1,6 +1,7 @@
-var http = require('http');
-var https = require('https');
-var fs = require('fs-extra');
+"use strict";
+var http = require("http");
+var https = require("https");
+var fs = require("fs-extra");
 
 
 function makeDirectory(path){
@@ -25,7 +26,7 @@ function download(url, file, callback){
 			// this might be an invalid path!
 			fs.stat(pathArray.join("/"), (err, stat) => {
 				if(err){
-					makeDirectory(pathArray.join("/")).then(()=>{
+					makeDirectory(pathArray.join("/")).then(() => {
 						doDownload(url, file, callback);
 					});
 				} else {
@@ -76,12 +77,12 @@ let downloadList = [
 		url: "https://fonts.googleapis.com/css?family=Roboto",
 		file: "static/external/css/Roboto.css",
 	},
-]
+];
 
 // initiate folder creations and downloads
 function processMkdirRecursive(callback){
 	let item = directories.shift();
-	makeDirectory(item).then(()=>{
+	makeDirectory(item).then(() => {
 		if(directories.length == 0){
 			if(callback) callback();
 		} else {
@@ -91,7 +92,7 @@ function processMkdirRecursive(callback){
 }
 function processDownloadRecursive(callback){
 	let item = downloadList.shift();
-	download(item.url, item.file, item.callback).then(()=>{
+	download(item.url, item.file, item.callback).then(() => {
 		if(downloadList.length == 0){
 			if(callback) callback();
 		} else {
diff --git a/lib/objectOps.js b/lib/objectOps.js
index 23053af3..1fe093cc 100644
--- a/lib/objectOps.js
+++ b/lib/objectOps.js
@@ -1,37 +1,39 @@
 /**
-Helper functions related to objects
-@module
-*/
+ * Helper functions related to objects
+ * @module
+ */
+"use strict";
 
 /**
-Deep clones an object, is actually just JSON.parse(JSON.stringify()) but looks cleaner.
-@param {object} obj to clone
-@returns {object}
-
-@example
-a = {"thingy":"with a value"};
-b = a;
-a == b; // true
-c = objectOps.deepclone(a);
-a == c; // false
-*/
+ * Deep clones an object, is actually just JSON.parse(JSON.stringify()) but looks cleaner.
+ * @param {object} obj to clone
+ * @returns {object} The cloned object.
+ *
+ * @example
+ * a = {"thingy":"with a value"};
+ * b = a;
+ * a == b; // true
+ * c = objectOps.deepclone(a);
+ * a == c; // false
+ */
 module.exports.deepclone = function(obj){
 	return JSON.parse(JSON.stringify(obj));
-}
-/**
-Checks if a string is valid JSON using try/catch. If passed an object it will always return true.
-@param {string} string to verify
-@returns {boolean}
+};
 
-@example
-objectOps.isJSON("99 bottles of beer"); // false
-objectOps.isJSON("99"); // true
-objectOps.isJSON({"thingy":"that is an object"}); // true
-objectOps.isJSON(JSON.stringify({"thingy":"that is an object"})); // true
-*/
+/**
+ * Checks if a string is valid JSON using try/catch. If passed an object it will always return true.
+ * @param {string} string to verify
+ * @returns {boolean} true if valid JSON.
+ *
+ * @example
+ * objectOps.isJSON("99 bottles of beer"); // false
+ * objectOps.isJSON("99"); // true
+ * objectOps.isJSON({"thingy":"that is an object"}); // true
+ * objectOps.isJSON(JSON.stringify({"thingy":"that is an object"})); // true
+ */
 module.exports.isJSON = function(string){
 	let stringIsJson = false;
-	let x
+	let x;
 	try {
 		x = JSON.parse(string);
 	} catch (e){
@@ -41,4 +43,4 @@ module.exports.isJSON = function(string){
 		stringIsJson = true;
 	}
 	return stringIsJson;
-}
+};
diff --git a/lib/plugin.js b/lib/plugin.js
index 20f8fed3..867e4048 100644
--- a/lib/plugin.js
+++ b/lib/plugin.js
@@ -9,6 +9,11 @@ const path = require("path");
 const errors = require("lib/errors");
 
 
+/**
+ * Conceptual base for master and instance plugins.
+ * @typedef {module:lib/plugin.BaseMasterPlugin|module:lib/plugin.BaseInstancePlugin} module:lib/plugin.BasePlugin
+ */
+
 /**
  * Base class for instance plugins
  * @static
@@ -51,7 +56,7 @@ class BaseInstancePlugin {
 	 * @param {module:lib/config.ConfigGroup} group -
 	 *     The group who's field got changed on.
 	 * @param {string} field - Name of the field that changed.
-	 * @param prev - The previous value of the field.
+	 * @param {*} prev - The previous value of the field.
 	 */
 	async onInstanceConfigFieldChanged(group, field, prev) { }
 
@@ -68,7 +73,7 @@ class BaseInstancePlugin {
 	 * the Gauges/Counters/etc in onMetric and let Clusterio deal will
 	 * collecting the values.
 	 *
-	 * @returns an async iterator of prometheus metric results or undefined.
+	 * @returns {*} an async iterator of prometheus metric results or undefined.
 	 */
 	async onMetrics() { }
 
@@ -99,16 +104,23 @@ class BaseInstancePlugin {
 	 *
 	 * Called when the Factorio server outputs a line on either stdout or
 	 * stderr.  The output is a parsed form of the line and contains the
-	 * following properties (those marked with ? are optional):
+	 * following properties:
 	 *
-	 * - source: Where the message came from, one of "stdout" and "stderr".
-	 * - format: Timestamp format, one of "date", "seconds" and "none".
-	 * - time?: Timestamp of the message.  Not present if format is "none".
-	 * - type: Type of message, one of "log", "action" and "generic".
-	 * - level?: Log level for "log" type.  i.e "Info" normally.
-	 * - file?: File reported for "log" type.
-	 * - action?: Kind of action for "action" type. i.e "CHAT" for chat.
-	 * - message: Main content of the line.
+	 * @param {Object} output - parsed server output.
+	 * @param {string} output.source -
+	 *     Where the message came from, one of "stdout" and "stderr".
+	 * @param {string} output.format -
+	 *     Timestamp format, one of "date", "seconds" and "none".
+	 * @param {string=} output.time -
+	 *     Timestamp of the message.  Not present if format is "none".
+	 * @param {string} output.type -
+	 *     Type of message, one of "log", "action" and "generic".
+	 * @param {string=} output.level -
+	 *     Log level for "log" type.  i.e "Info" normally.
+	 * @param {string=} output.file - File reported for "log" type.
+	 * @param {string=} output.action -
+	 *     Kind of action for "action" type. i.e "CHAT" for chat.
+	 * @param {string} output.message - Main content of the line.
 	 */
 	async onOutput(output) { }
 
@@ -215,7 +227,7 @@ class BaseMasterPlugin {
 	 * the Gauges/Counters/etc in onMetric and let Clusterio deal will
 	 * collecting the values.
 	 *
-	 * @returns an async iterator of prometheus metric results or undefined.
+	 * @returns {*} an async iterator of prometheus metric results or undefined.
 	 */
 	async onMetrics() { }
 
@@ -249,9 +261,9 @@ class BaseMasterPlugin {
 	 *
 	 * Invoked when the connection to the slave has been closed.
 	 *
-	 * @param {string} event - one of connect, drop, and close
 	 * @param {module:master~SlaveConnection} connection -
 	 *     The connection the event occured on.
+	 * @param {string} event - one of connect, drop, and close
 	 */
 	onSlaveConnectionEvent(connection, event) { }
 
@@ -311,6 +323,7 @@ class BaseMasterPlugin {
  * module.  Once loaded the info modules will not be reloaded should this
  * function be called again.
  *
+ * @param {string} baseDir - posix relative path to plugin directory.
  * @returns {Map<string, Object>} mapping of plugin name to info module.
  * @static
  */
@@ -321,10 +334,10 @@ async function loadPluginInfos(baseDir) {
 
 		try {
 			// Note: Require path is relative to this module
-			pluginInfo = require(path.posix.join('..', baseDir, pluginDir, 'info'));
+			pluginInfo = require(path.posix.join("..", baseDir, pluginDir, "info"));
 
 		} catch (err) {
-			if (err.code === 'MODULE_NOT_FOUND') {
+			if (err.code === "MODULE_NOT_FOUND") {
 				continue;
 			} else {
 				throw new errors.PluginError(pluginDir, err);
@@ -350,7 +363,8 @@ async function loadPluginInfos(baseDir) {
  *
  * @param {module:lib/link.Link} link - Link to attach handlers to.
  * @param {object} pluginInfo - Plugin info object.
- * @param plugin - The instance of the plugin to use handlers from.
+ * @param {module:lib/plugin.BasePlugin} plugin -
+ *     The instance of the plugin to use handlers from.
  */
 function attachPluginMessages(link, pluginInfo, plugin) {
 	let messageDefinitions = pluginInfo.messages || [];
@@ -359,7 +373,7 @@ function attachPluginMessages(link, pluginInfo, plugin) {
 			throw new Error(`Type of ${name} message must start with "${pluginInfo.name}:"`);
 		}
 
-		let handler = name + messageFormat.constructor.name + 'Handler';
+		let handler = name + messageFormat.constructor.name + "Handler";
 		if (plugin === null || !plugin[handler]) {
 			messageFormat.attach(link);
 
@@ -374,7 +388,7 @@ function attachPluginMessages(link, pluginInfo, plugin) {
 /**
  * Invokes the given hook on all plugins
  *
- * @param {Map<string, Object} plugins -
+ * @param {Map<string, Object>} plugins -
  *     Mapping of plugin names to plugins to invoke the hook on.
  * @param {string} hook - Name of hook to invoke.
  * @param {...*} args - Arguments to pass on to the hook.
diff --git a/lib/prometheus.js b/lib/prometheus.js
index 8913f52a..b461d60d 100644
--- a/lib/prometheus.js
+++ b/lib/prometheus.js
@@ -1,10 +1,11 @@
+"use strict";
 class Metric {
 	constructor(type, name, help, labels = []) {
-		if (typeof name !== 'string') {
+		if (typeof name !== "string") {
 			throw new Error("Expected name to be a string");
 		}
 
-		if (typeof help !== 'string') {
+		if (typeof help !== "string") {
 			throw new Error("Expected help to be a string");
 		}
 
@@ -46,7 +47,7 @@ function escapeLabelValue(value) {
 }
 
 function labelsToKey(labels, metricLabels) {
-	let items = []
+	let items = [];
 	if (labels.length === 1 && typeof labels[0] === "object") {
 		labels = labels[0];
 		for (let name of metricLabels) {
@@ -73,7 +74,7 @@ function labelsToKey(labels, metricLabels) {
 		}
 
 		if (labels.length > metricLabels.length) {
-			throw new Error(`Extra positional label`);
+			throw new Error("Extra positional label");
 		}
 
 		for (let i=0; i < metricLabels.length; ++i) {
@@ -86,14 +87,14 @@ function labelsToKey(labels, metricLabels) {
 		}
 	}
 
-	return items.join(',');
+	return items.join(",");
 }
 
 function keyToLabels(key) {
 	let labels = new Map();
 
-	if (key !== '') for (let pair of key.split(',')) {
-		let [name, value] = pair.split('=', 2);
+	if (key !== "") for (let pair of key.split(",")) {
+		let [name, value] = pair.split("=", 2);
 		labels.set(name, value
 			.slice(1, -1)
 			.replace(/\\"/g, "\"")
@@ -111,9 +112,9 @@ class ValueCollector extends Collector {
 		let register = true;
 		let callback = null;
 		for (let [name, value] of Object.entries(options)) {
-			if (name === 'labels') { labels = value; }
-			else if (name === 'register') { register = value; }
-			else if (name === 'callback') { callback = value; }
+			if (name === "labels") { labels = value; }
+			else if (name === "register") { register = value; }
+			else if (name === "callback") { callback = value; }
 			else { throw new Error(`Unrecognized option '${name}'`); }
 		}
 
@@ -151,7 +152,7 @@ class ValueCollector extends Collector {
 
 	remove(...labels) {
 		let key = labelsToKey(labels, this.metric.labels);
-		if (key === '') {
+		if (key === "") {
 			throw new Error("labels cannot be empty");
 		}
 		this._children.delete(key);
@@ -166,11 +167,11 @@ class ValueCollector extends Collector {
 		function removeMatchingLabels(mapping, labels) {
 			for (let key of mapping.keys()) {
 				let candidate = keyToLabels(key);
-				let hasLabels = Object.entries(labels).every(([name, value]) => {
-					return candidate.get(name) === value;
-				});
+				let hasLabels = Object.entries(labels).every(([name, value]) => (
+					candidate.get(name) === value
+				));
 				if (hasLabels) {
-					mapping.delete(key)
+					mapping.delete(key);
 				}
 			}
 		}
@@ -208,7 +209,7 @@ class CounterChild extends ValueCollectorChild {
 			throw new Error("Expected value to be a positive number");
 		}
 
-		this._values.set(this._key, this._values.get(this._key) + value)
+		this._values.set(this._key, this._values.get(this._key) + value);
 	}
 }
 
@@ -224,19 +225,19 @@ class Counter extends ValueCollector {
 
 class GaugeChild extends ValueCollectorChild {
 	inc(value = 1) {
-		this._values.set(this._key, this._values.get(this._key) + value)
+		this._values.set(this._key, this._values.get(this._key) + value);
 	}
 
 	dec(value = 1) {
-		this._values.set(this._key, this._values.get(this._key) - value)
+		this._values.set(this._key, this._values.get(this._key) - value);
 	}
 
 	set(value) {
-		this._values.set(this._key, value)
+		this._values.set(this._key, value);
 	}
 
 	setToCurrentTime() {
-		this._values.set(this._key, Date.now() / 1000)
+		this._values.set(this._key, Date.now() / 1000);
 	}
 }
 
@@ -309,9 +310,9 @@ function escapeHelp(help) {
 
 function formatValue(value) {
 	if (value === Infinity) {
-		return '+Inf';
+		return "+Inf";
 	} else if (value === -Infinity) {
-		return '-Inf';
+		return "-Inf";
 	} else {
 		return value.toString();
 	}
@@ -323,14 +324,14 @@ async function* expositionLines(resultsIterator) {
 		if (first) {
 			first = false;
 		} else {
-			yield `\n`
+			yield "\n";
 		}
 
 		yield `# HELP ${result.metric.name} ${escapeHelp(result.metric.help)}\n`;
 		yield `# TYPE ${result.metric.name} ${result.metric.type}\n`;
 
 		for (let [key, value] of result.samples) {
-			if (key === '') {
+			if (key === "") {
 				yield `${result.metric.name} ${formatValue(value)}\n`;
 			} else {
 				yield `${result.metric.name}{${key}} ${formatValue(value)}\n`;
@@ -340,7 +341,7 @@ async function* expositionLines(resultsIterator) {
 }
 
 async function exposition(resultsIterator = defaultRegistry.collect()) {
-	let exposition = '';
+	let exposition = "";
 	for await (let line of expositionLines(resultsIterator)) {
 		exposition += line;
 	}
@@ -348,16 +349,16 @@ async function exposition(resultsIterator = defaultRegistry.collect()) {
 }
 
 // HTTP Content-Type for the exposition format that's implemented
-exposition.contentType = 'text/plain; version=0.0.4';
+exposition.contentType = "text/plain; version=0.0.4";
 
 function serializeResult(result, options = {}) {
 	let addLabels = null;
 	let metricName = result.metric.name;
 	let metricHelp = result.metric.help;
 	for (let [name, value] of Object.entries(options)) {
-		if (name === 'addLabels') { addLabels = value; }
-		else if (name === 'metricName') { metricName = value; }
-		else if (name === 'metricHelp') { metricHelp = value; }
+		if (name === "addLabels") { addLabels = value; }
+		else if (name === "metricName") { metricName = value; }
+		else if (name === "metricHelp") { metricHelp = value; }
 		else { throw new Error(`Unrecognized option '${name}'`); }
 	}
 
@@ -370,7 +371,7 @@ function serializeResult(result, options = {}) {
 		samples = new Map();
 		let key = labelsToKey([addLabels], [...Object.keys(addLabels)]);
 		for (let [labels, value] of result.samples.entries()) {
-			if (labels === '') { samples.set(key, value); }
+			if (labels === "") { samples.set(key, value); }
 			else { samples.set(`${labels},${key}`, value); }
 		}
 	}
@@ -395,12 +396,12 @@ function deserializeResult(serializedResult) {
 			serializedResult.metric.labels,
 		),
 		samples: new Map(serializedResult.samples),
-	}
+	};
 }
 
 let defaultCollectors = {};
 defaultCollectors.processCpuSecondsTotal = new Gauge(
-	'process_cpu_seconds_total',
+	"process_cpu_seconds_total",
 	"Total user and system CPU time spent in seconds.",
 	{
 		callback: async function() {
@@ -411,7 +412,7 @@ defaultCollectors.processCpuSecondsTotal = new Gauge(
 );
 
 defaultCollectors.processResidentMemoryBytes = new Gauge(
-	'process_resident_memory_bytes',
+	"process_resident_memory_bytes",
 	"Resident memory size in bytes.",
 	{
 		callback: function() {
@@ -421,7 +422,7 @@ defaultCollectors.processResidentMemoryBytes = new Gauge(
 );
 
 defaultCollectors.processHeapBytes = new Gauge(
-	'process_heap_bytes',
+	"process_heap_bytes",
 	"Process heap size in bytes.",
 	{
 		callback: function() {
@@ -431,7 +432,7 @@ defaultCollectors.processHeapBytes = new Gauge(
 );
 
 defaultCollectors.processStartTimeSeconds = new Gauge(
-	'process_start_time_seconds',
+	"process_start_time_seconds",
 	"Start time of the process since unix epoch in seconds."
 );
 defaultCollectors.processStartTimeSeconds.setToCurrentTime();
diff --git a/lib/schema.js b/lib/schema.js
index 84fc6de0..66f038bd 100644
--- a/lib/schema.js
+++ b/lib/schema.js
@@ -2,7 +2,8 @@
  * JSON schemas used for validating link messages
  * @module
  */
-const ajv = new (require('ajv'))({
+"use strict";
+const ajv = new (require("ajv"))({
 	verbose: true,
 	format: "full",
 	extendRefs: "fail",
@@ -73,7 +74,7 @@ const serverHandshake = ajv.compile({
 	$schema: "http://json-schema.org/draft-07/schema#",
 	title: "Server Handshake",
 	description: "Message sent from the server to a client during the handshake",
-	allOf: [ messageSchema ],
+	allOf: [messageSchema],
 	anyOf: [
 		{
 			properties: {
@@ -87,7 +88,7 @@ const serverHandshake = ajv.compile({
 							type: "object",
 							additionalProperties: { type: "string" },
 						},
-					}
+					},
 				},
 			},
 		},
@@ -136,7 +137,7 @@ const clientHandshake = ajv.compile({
 	$schema: "http://json-schema.org/draft-07/schema#",
 	title: "Client Message",
 	description: "Message sent from a client to the server",
-	allOf: [ messageSchema ],
+	allOf: [messageSchema],
 	anyOf: [
 		{
 			properties: {
@@ -168,7 +169,7 @@ const clientHandshake = ajv.compile({
 						"token": { type: "string" },
 						"agent": { type: "string" },
 						"version": { type: "string" },
-					}
+					},
 				},
 			},
 		},
diff --git a/lib/users.js b/lib/users.js
index 4cc855fb..11ef3fde 100644
--- a/lib/users.js
+++ b/lib/users.js
@@ -53,7 +53,7 @@ function definePermission({ name, title, description, grantByDefault=false }) {
 	}
 
 	if (permissions.has(name)) {
-		throw new Error(`Permission '${name}' is already defined`)
+		throw new Error(`Permission '${name}' is already defined`);
 	}
 
 	permissions.set(name, new Permission(name, title, description, grantByDefault));
@@ -95,6 +95,7 @@ class Role {
  *
  * Ensures the role with id 0 exisits and has the core.admin permission.
  *
+ * @param {Map<number, module:lib/user.Role>} roles - role storage to modify.
  * @returns {module:lib/permission.Role} the default admin role
  * @static
  */
@@ -115,7 +116,7 @@ function ensureDefaultAdminRole(roles) {
  * assigned by default.  Note that this may not be the same role as the one
  * that is assigned to new users by default.
  *
- * @returns {module:lib/permission.Role} the default player role
+ * @param {Map<number, module:lib/user.Role>} roles - role storage to modify.
  * @static
  */
 function ensureDefaultPlayerRole(roles) {
@@ -156,7 +157,7 @@ class User {
 
 		/**
 		 * Roles this user has
-		 * @type {Set<module:lib/permissions.Role}
+		 * @type {Set<module:lib/permissions.Role>}
 		 */
 		this.roles = new Set();
 		if (roles) {
@@ -186,6 +187,7 @@ class User {
 	 * Generate access token for this user
 	 *
 	 * @param {string} secret - Secret to sign token with.
+	 * @returns {string} JWT access token for the user.
 	 */
 	createToken(secret) {
 		return jwt.sign({ aud: "user", user: this.name }, secret);
@@ -197,7 +199,7 @@ class User {
 	 * Sets the tokenValidAfter property to the current time, which causes
 	 * all currently issued tokens for the user to become invalid.
 	 */
-	invalidateToken(secret) {
+	invalidateToken() {
 		this.tokenValidAfter = Math.floor(Date.now() / 1000);
 	}
 
@@ -208,6 +210,7 @@ class User {
 	 * permission.  If the permission is not granted for the user a
 	 * "Permission denied" error is thrown.
 	 *
+	 * @param {string} permission - The permission to check for.
 	 * @throws {Error} if the user does noh have the given permission.
 	 */
 	checkPermission(permission) {
diff --git a/master.js b/master.js
index f8210c09..234bd8bc 100644
--- a/master.js
+++ b/master.js
@@ -16,11 +16,12 @@
 // const updater = require("./updater");
 // updater.update().then(console.log);
 
+"use strict";
 const deepmerge = require("deepmerge");
 const path = require("path");
 const fs = require("fs-extra");
-const jwt = require('jsonwebtoken');
-const crypto = require('crypto');
+const jwt = require("jsonwebtoken");
+const crypto = require("crypto");
 const moment = require("moment");
 const request = require("request");
 const setBlocking = require("set-blocking");
@@ -49,30 +50,30 @@ const config = require("lib/config");
 const users = require("lib/users");
 
 const express = require("express");
-const compression = require('compression');
-const cookieParser = require('cookie-parser');
+const compression = require("compression");
+const cookieParser = require("cookie-parser");
 // Required for express post requests
 const bodyParser = require("body-parser");
-const fileUpload = require('express-fileupload');
+const fileUpload = require("express-fileupload");
 var app = express();
 var httpServer;
 var httpsServer;
 
 app.use(cookieParser());
 app.use(bodyParser.json({
-	limit: '10mb',
+	limit: "10mb",
 }));
 app.use(bodyParser.urlencoded({
 	parameterLimit: 100000,
-	limit: '10mb',
-	extended: true
+	limit: "10mb",
+	extended: true,
 }));
 app.use(fileUpload());
 app.use(compression());
 
 // dynamic HTML generations with EJS
-app.set('view engine', 'ejs');
-app.set('views', ['views', 'plugins']);
+app.set("view engine", "ejs");
+app.set("views", ["views", "plugins"]);
 
 // give ejs access to some interesting information
 app.use(function(req, res, next){
@@ -88,12 +89,12 @@ app.use(function(req, res, next){
 
 require("./routes")(app);
 // Set folder to serve static content from (the website)
-app.use(express.static('static'));
+app.use(express.static("static"));
 
 const endpointHitCounter = new prometheus.Counter(
 	"clusterio_master_http_endpoint_hits_total",
 	"How many requests a particular HTTP endpoint has gotten",
-	{ labels: ['route'] }
+	{ labels: ["route"] }
 );
 
 const wsMessageCounter = new prometheus.Counter(
@@ -126,11 +127,11 @@ const wsActiveSlavesGauge = new prometheus.Gauge(
 async function getMetrics(req, res, next) {
 	endpointHitCounter.labels(req.route.path).inc();
 
-	let results = []
+	let results = [];
 	let pluginResults = await plugin.invokeHook(masterPlugins, "onMetrics");
 	for (let metricIterator of pluginResults) {
 		for await (let metric of metricIterator) {
-			results.push(metric)
+			results.push(metric);
 		}
 	}
 
@@ -167,10 +168,10 @@ async function getMetrics(req, res, next) {
 
 
 	let text = await prometheus.exposition(results);
-	res.set('Content-Type', prometheus.exposition.contentType);
+	res.set("Content-Type", prometheus.exposition.contentType);
 	res.send(text);
 }
-app.get('/metrics', (req, res, next) => getMetrics(req, res, next).catch(next));
+app.get("/metrics", (req, res, next) => getMetrics(req, res, next).catch(next));
 
 
 function validateSlaveToken(req, res, next) {
@@ -232,9 +233,9 @@ app.put("/api/upload-export",
 );
 
 const masterConnectedClientsCount = new prometheus.Gauge(
-	'clusterio_master_connected_clients_count', "How many clients are currently connected to this master server",
+	"clusterio_master_connected_clients_count", "How many clients are currently connected to this master server",
 	{
-		labels: ['type'], callback: async function(gauge) {
+		labels: ["type"], callback: async function(gauge) {
 			gauge.labels("slave").set(slaveConnections.size);
 			gauge.labels("control").set(controlConnections.length);
 		},
@@ -246,6 +247,10 @@ const db = {};
 
 /**
  * Load Map from JSON file in the database directory.
+ *
+ * @param {string} databaseDirectory - Path to master database directory.
+ * @param {string} file - Name of file to load.
+ * @returns {Map} file loaded as a map.
  */
 async function loadMap(databaseDirectory, file) {
 	let databasePath = path.resolve(databaseDirectory, file);
@@ -267,7 +272,7 @@ async function loadInstances(databaseDirectory, file) {
 		}
 
 	} catch (err) {
-		if (err.code !== 'ENOENT') {
+		if (err.code !== "ENOENT") {
 			throw err;
 		}
 	}
@@ -314,17 +319,21 @@ async function loadUsers(databaseDirectory, file) {
  */
 function createUser(name) {
 	if (db.users.has(name)) {
-		throw new Error(`User '${name}' already exists`)
+		throw new Error(`User '${name}' already exists`);
 	}
 
 	let defaultRoleId = masterConfig.get("master.default_role_id");
-	user = new users.User({ name, roles: [defaultRoleId] }, db.roles);
+	let user = new users.User({ name, roles: [defaultRoleId] }, db.roles);
 	db.users.set(name, user);
 	return user;
 }
 
 /**
  * Save Map to JSON file in the database directory.
+ *
+ * @param {string} databaseDirectory - Path to master database directory.
+ * @param {string} file - Name of file to save.
+ * @param {Map} map - Mapping to save into file.
  */
 async function saveMap(databaseDirectory, file, map) {
 	let databasePath = path.resolve(databaseDirectory, file);
@@ -365,14 +374,14 @@ async function saveUsers(databaseDirectory, file) {
  * Innitiate shutdown of master server
  */
 async function shutdown() {
-	console.log('Shutting down');
+	console.log("Shutting down");
 	let exitStartTime = Date.now();
 	try {
 		console.log("Saving configs");
 		await fs.outputFile(masterConfigPath, JSON.stringify(masterConfig.serialize(), null, 4));
 
-		await saveMap(masterConfig.get('master.database_directory'), "slaves.json", db.slaves);
-		await saveInstances(masterConfig.get('master.database_directory'), "instances.json", db.instances);
+		await saveMap(masterConfig.get("master.database_directory"), "slaves.json", db.slaves);
+		await saveInstances(masterConfig.get("master.database_directory"), "instances.json", db.instances);
 		await saveUsers(masterConfig.get("master.database_directory"), "users.json");
 
 		await plugin.invokeHook(masterPlugins, "onShutdown");
@@ -439,7 +448,7 @@ async function downloadPage(url) {
 app.get("/api/modmeta", async function(req, res) {
 	endpointHitCounter.labels(req.route.path).inc();
 	res.header("Access-Control-Allow-Origin", "*");
-	res.setHeader('Content-Type', 'application/json');
+	res.setHeader("Content-Type", "application/json");
 	let modData = await downloadPage("https://mods.factorio.com/api/mods/" + req.query.modname);
 	res.send(modData);
 });
@@ -452,7 +461,7 @@ app.get("/api/modmeta", async function(req, res) {
  */
 class BaseConnection extends link.Link {
 	constructor(target, connector) {
-		super('master', target, connector);
+		super("master", target, connector);
 		link.attachAllMessages(this);
 		for (let masterPlugin of masterPlugins.values()) {
 			plugin.attachPluginMessages(this, masterPlugin.info, masterPlugin);
@@ -465,7 +474,7 @@ class BaseConnection extends link.Link {
 			throw new errors.RequestError(`Instance with ID ${message.data.instance_id} does not exist`);
 		}
 
-		let slaveId = instance.config.get('instance.assigned_slave');
+		let slaveId = instance.config.get("instance.assigned_slave");
 		if (slaveId === null) {
 			throw new errors.RequestError("Instance is not assigned to a slave");
 		}
@@ -475,7 +484,7 @@ class BaseConnection extends link.Link {
 			throw new errors.RequestError("Slave containing instance is not connected");
 		}
 		if (request.plugin && !connection.plugins.has(request.plugin)) {
-			throw new errors.RequestError(`Slave containing instance does not have ${request.plugin} plugin`)
+			throw new errors.RequestError(`Slave containing instance does not have ${request.plugin} plugin`);
 		}
 
 		return await request.send(connection, message.data);
@@ -485,7 +494,7 @@ class BaseConnection extends link.Link {
 		let instance = db.instances.get(message.data.instance_id);
 		if (!instance) { return; }
 
-		let slaveId = instance.config.get('instance.assigned_slave');
+		let slaveId = instance.config.get("instance.assigned_slave");
 		if (slaveId === null) { return; }
 
 		let connection = slaveConnections.get(slaveId);
@@ -526,10 +535,10 @@ class BaseConnection extends link.Link {
 	}
 }
 
-let controlConnections = new Array();
+let controlConnections = [];
 class ControlConnection extends BaseConnection {
 	constructor(registerData, connector, user) {
-		super('control', connector)
+		super("control", connector);
 
 		this._agent = registerData.agent;
 		this._version = registerData.version;
@@ -551,7 +560,7 @@ class ControlConnection extends BaseConnection {
 
 		this.ws_dumper = null;
 		this.connector.on("connect", () => {
-			this.connector._socket.clusterio_ignore_dump = !!this.ws_dumper;
+			this.connector._socket.clusterio_ignore_dump = Boolean(this.ws_dumper);
 		});
 		this.connector.on("close", () => {
 			if (this.ws_dumper) {
@@ -617,7 +626,7 @@ class ControlConnection extends BaseConnection {
 		let instanceConfig = new config.InstanceConfig();
 		await instanceConfig.load(message.data.serialized_config);
 
-		let instanceId = instanceConfig.get("instance.id")
+		let instanceId = instanceConfig.get("instance.id");
 		if (db.instances.has(instanceId)) {
 			throw new errors.RequestError(`Instance with ID ${instanceId} already exists`);
 		}
@@ -630,7 +639,7 @@ class ControlConnection extends BaseConnection {
 			throw new errors.RequestError(`Instance with ID ${message.data.instance_id} does not exist`);
 		}
 
-		if (instance.config.get('instance.assigned_slave') !== null) {
+		if (instance.config.get("instance.assigned_slave") !== null) {
 			await this.forwardRequestToInstance(message, request);
 		}
 		db.instances.delete(message.data.instance_id);
@@ -644,7 +653,7 @@ class ControlConnection extends BaseConnection {
 
 		return {
 			serialized_config: instance.config.serialize(),
-		}
+		};
 	}
 
 	async updateInstanceConfig(instance) {
@@ -685,7 +694,7 @@ class ControlConnection extends BaseConnection {
 			throw new errors.RequestError(`Instance with ID ${message.data.instance_id} does not exist`);
 		}
 
-		let {field, prop, value} = message.data;
+		let { field, prop, value } = message.data;
 		instance.config.setProp(field, prop, value);
 		await this.updateInstanceConfig(instance);
 	}
@@ -708,7 +717,7 @@ class ControlConnection extends BaseConnection {
 			throw new errors.RequestError("Target slave is not connected to the master server");
 		}
 
-		instance.config.set("instance.assigned_slave", message.data.slave_id)
+		instance.config.set("instance.assigned_slave", message.data.slave_id);
 
 		return await link.messages.assignInstance.send(connection, {
 			instance_id: instance.config.get("instance.id"),
@@ -750,7 +759,7 @@ class ControlConnection extends BaseConnection {
 
 		// Start at 5 to leave space for future default roles
 		let id = Math.max(5, lastId+1);
-		db.roles.set(id, new users.Role({ id, ...message.data}));
+		db.roles.set(id, new users.Role({ id, ...message.data }));
 		return { id };
 	}
 
@@ -836,7 +845,7 @@ class ControlConnection extends BaseConnection {
 			}
 		};
 		this.connector._socket.clusterio_ignore_dump = true;
-		debugEvents.on("message", this.ws_dumper)
+		debugEvents.on("message", this.ws_dumper);
 	}
 }
 
@@ -848,7 +857,7 @@ var slaveConnections = new Map();
  */
 class SlaveConnection extends BaseConnection {
 	constructor(registerData, connector) {
-		super('slave', connector);
+		super("slave", connector);
 
 		this._agent = registerData.agent;
 		this._id = registerData.id;
@@ -871,6 +880,7 @@ class SlaveConnection extends BaseConnection {
 		});
 
 		for (let event of ["connect", "drop", "close"]) {
+			// eslint-disable-next-line no-loop-func
 			this.connector.on(event, () => {
 				for (let masterPlugin of masterPlugins.values()) {
 					masterPlugin.onSlaveConnectionEvent(this, event);
@@ -883,7 +893,7 @@ class SlaveConnection extends BaseConnection {
 		let instance = db.instances.get(message.data.instance_id);
 		let prev = instance.status;
 		instance.status = "initialized";
-		console.log(`Clusterio | Instance ${instance.config.get("instance.name")} Initialized`)
+		console.log(`Clusterio | Instance ${instance.config.get("instance.name")} Initialized`);
 		await plugin.invokeHook(masterPlugins, "onInstanceStatusChanged", instance, prev);
 	}
 
@@ -891,7 +901,7 @@ class SlaveConnection extends BaseConnection {
 		let instance = db.instances.get(message.data.instance_id);
 		let prev = instance.status;
 		instance.status = "running";
-		console.log(`Clusterio | Instance ${instance.config.get("instance.name")} Started`)
+		console.log(`Clusterio | Instance ${instance.config.get("instance.name")} Started`);
 		await plugin.invokeHook(masterPlugins, "onInstanceStatusChanged", instance, prev);
 	}
 
@@ -899,7 +909,7 @@ class SlaveConnection extends BaseConnection {
 		let instance = db.instances.get(message.data.instance_id);
 		let prev = instance.status;
 		instance.status = "stopped";
-		console.log(`Clusterio | Instance ${instance.config.get("instance.name")} Stopped`)
+		console.log(`Clusterio | Instance ${instance.config.get("instance.name")} Stopped`);
 		await plugin.invokeHook(masterPlugins, "onInstanceStatusChanged", instance, prev);
 	}
 
@@ -919,7 +929,7 @@ class SlaveConnection extends BaseConnection {
 			let instanceConfig = new config.InstanceConfig();
 			await instanceConfig.load(instance.serialized_config);
 
-			let masterInstance = db.instances.get(instanceConfig.get("instance.id"))
+			let masterInstance = db.instances.get(instanceConfig.get("instance.id"));
 			if (masterInstance) {
 				// Already have this instance, update state instead
 				if (masterInstance.status !== instance.status) {
@@ -951,7 +961,7 @@ class SlaveConnection extends BaseConnection {
 	}
 
 	async playerEventEventHandler(message) {
-		let {instance_id, name, type} = message.data;
+		let { instance_id, name, type } = message.data;
 		let user = db.users.get(name);
 		if (!user) {
 			user = createUser(name);
@@ -976,13 +986,13 @@ const wss = new WebSocket.Server({
 /**
  * Returns true if value is a signed 32-bit integer
  *
- * @param value - value to test.
+ * @param {number} value - value to test.
  * @returns {Boolean}
  *     true if value is an integer between -2<sup>31</sup> and
  *     2<sup>31</sup>-1.
  */
 function isInteger(value) {
-	return value | 0 === value;
+	return (value | 0) === value;
 }
 
 
@@ -1020,9 +1030,12 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 	 * Send ready over the socket
 	 *
 	 * Sends the ready message over the socket to initiate the session.
+	 *
+	 * @param {string} sessionToken -
+	 *     the session token to send to the client.
 	 */
 	ready(sessionToken) {
-		this._heartbeatInterval = masterConfig.get("master.heartbeat_interval")
+		this._heartbeatInterval = masterConfig.get("master.heartbeat_interval");
 		this._socket.send(JSON.stringify({
 			seq: null,
 			type: "ready",
@@ -1043,6 +1056,9 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 	 *
 	 * Terminates the current socket and contiunes the session over the
 	 * socket given from the message sequence given.
+	 *
+	 * @param {module:net.Socket} socket - New socket to continue on.
+	 * @param {number} lastSeq - The last message the client received.
 	 */
 	continue(socket, lastSeq) {
 		this._socket.terminate();
@@ -1053,7 +1069,7 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 			this._timeoutId = null;
 		}
 
-		this._heartbeatInterval = masterConfig.get("master.heartbeat_interval")
+		this._heartbeatInterval = masterConfig.get("master.heartbeat_interval");
 		this._socket.send(JSON.stringify({
 			seq: null,
 			type: "continue",
@@ -1078,7 +1094,7 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 			clearTimeout(this._timeoutId);
 		}
 
-		this._timeoutId = setTimeout(() => { this._timedOut() }, timeout * 1000);
+		this._timeoutId = setTimeout(() => { this._timedOut(); }, timeout * 1000);
 		this._timeout = timeout;
 	}
 
@@ -1117,7 +1133,7 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 			} else {
 				this._state = "handshake";
 				this.emit("drop");
-				this._timeoutId = setTimeout(() => { this._timedOut() }, this._timeout * 1000);
+				this._timeoutId = setTimeout(() => { this._timedOut(); }, this._timeout * 1000);
 			}
 
 			this.stopHeartbeat();
@@ -1163,6 +1179,9 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 	 * Close the connection with the given reason.
 	 *
 	 * Sends a close frame and disconnects the connector.
+	 *
+	 * @param {number} code - WebSocket close code.
+	 * @param {string} reason - WebSocket close reason.
 	 */
 	async close(code, reason) {
 		if (this._state === "closed") {
@@ -1172,7 +1191,7 @@ class WebSocketServerConnector extends link.WebSocketBaseConnector {
 		this.stopHeartbeat();
 		this._state = "closing";
 		this._socket.close(code, reason);
-		await events.once(this, "close")
+		await events.once(this, "close");
 	}
 }
 
@@ -1202,7 +1221,7 @@ wss.on("connection", function (socket, req) {
 	// Start connection handshake.
 	socket.send(JSON.stringify({ seq: null, type: "hello", data: {
 		version,
-		plugins: pluginList
+		plugins: pluginList,
 	}}));
 
 	function attachHandler() {
@@ -1283,7 +1302,7 @@ async function handleHandshake(message, socket, req, attachHandler) {
 		}
 
 		connector.continue(socket, data.last_seq);
-		return
+		return;
 	}
 
 	if (stopAcceptingNewSessions) {
@@ -1332,7 +1351,7 @@ async function handleHandshake(message, socket, req, attachHandler) {
 	}
 
 	let sessionId = nextSessionId++;
-	let sessionToken = jwt.sign({ aud: masterSession, sid: sessionId, }, masterConfig.get("master.auth_secret"));
+	let sessionToken = jwt.sign({ aud: masterSession, sid: sessionId }, masterConfig.get("master.auth_secret"));
 	let connector = new WebSocketServerConnector(socket, sessionId);
 	activeConnectors.set(sessionId, connector);
 
@@ -1365,7 +1384,7 @@ async function pluginManagement(pluginInfos) {
 
 async function loadPlugins(pluginInfos) {
 	let plugins = new Map();
-	for (pluginInfo of pluginInfos) {
+	for (let pluginInfo of pluginInfos) {
 		if (!masterConfig.group(pluginInfo.name).get("enabled")) {
 			continue;
 		}
@@ -1386,7 +1405,7 @@ async function loadPlugins(pluginInfos) {
 			plugins.set(pluginInfo.name, masterPlugin);
 
 		} catch (err) {
-			throw new errors.PluginError(pluginInfo.name, err)
+			throw new errors.PluginError(pluginInfo.name, err);
 		}
 
 		console.log(`Clusterio | Loaded plugin ${pluginInfo.name} in ${Date.now() - pluginLoadStarted}ms`);
@@ -1398,6 +1417,10 @@ async function loadPlugins(pluginInfos) {
  * Calls listen on server capturing any errors that occurs
  * binding to the port.  Also adds handler for WebSocket
  * upgrade event.
+ *
+ * @param {module:net.Server} server - Server to start the listening on.
+ * @param {*} args - Arguments to the .listen() call on the server.
+ * @returns {Promise} promise that resolves the server is listening.
  */
 function listen(server, ...args) {
 	return new Promise((resolve, reject) => {
@@ -1407,7 +1430,7 @@ function listen(server, ...args) {
 			// For reasons that defy common sense, the connection event has
 			// to be emitted explictly when using noServer.
 			wss.handleUpgrade(req, socket, head, (ws) => {
-				wss.emit('connection', ws, req);
+				wss.emit("connection", ws, req);
 			});
 		});
 
@@ -1417,9 +1440,9 @@ function listen(server, ...args) {
 			));
 		}
 
-		server.once('error', wrapError);
+		server.once("error", wrapError);
 		server.listen(...args, () => {
-			server.off('error', wrapError);
+			server.off("error", wrapError);
 			resolve();
 		});
 	});
@@ -1431,9 +1454,11 @@ function _setConfig(config) {
 
 /**
  * Returns the URL needed to connect to the master server.
+ *
+ * @returns {string} master URL.
  */
 function getMasterUrl() {
-	let url = masterConfig.get("master.external_address")
+	let url = masterConfig.get("master.external_address");
 	if (!url) {
 		if (masterConfig.get("master.https_port")) {
 			url = `https://localhost:${masterConfig.get("master.https_port")}/`;
@@ -1450,7 +1475,7 @@ async function startServer() {
 	process.title = "clusterioMaster";
 
 	// add better stack traces on promise rejection
-	process.on('unhandledRejection', r => console.log(r));
+	process.on("unhandledRejection", r => console.log(r));
 
 	// argument parsing
 	let args = yargs
@@ -1472,7 +1497,7 @@ async function startServer() {
 						nargs: 1, default: "config-control.json",
 					});
 				})
-				.demandCommand(1, "You need to specify a command to run")
+				.demandCommand(1, "You need to specify a command to run");
 		})
 		.command("run", "Run master server")
 		.demandCommand(1, "You need to specify a command to run")
@@ -1481,7 +1506,7 @@ async function startServer() {
 	;
 
 	console.log("Loading Plugin info");
-	let pluginInfos = await plugin.loadPluginInfos("plugins")
+	let pluginInfos = await plugin.loadPluginInfos("plugins");
 	config.registerPluginConfigGroups(pluginInfos);
 	config.finalizeConfigs();
 
@@ -1492,7 +1517,7 @@ async function startServer() {
 		await masterConfig.load(JSON.parse(await fs.readFile(masterConfigPath)));
 
 	} catch (err) {
-		if (err.code === 'ENOENT') {
+		if (err.code === "ENOENT") {
 			console.log("Config not found, initializing new config");
 			await masterConfig.init();
 
@@ -1554,8 +1579,8 @@ async function startServer() {
 
 	// If we get here the command was run
 
-	let secondSigint = false
-	process.on('SIGINT', () => {
+	let secondSigint = false;
+	process.on("SIGINT", () => {
 		if (secondSigint) {
 			console.log("Caught second interrupt, terminating immediately");
 			process.exit(1);
@@ -1567,28 +1592,28 @@ async function startServer() {
 	});
 
 	// terminal closed
-	process.on('SIGHUP', () => {
+	process.on("SIGHUP", () => {
 		// No graceful cleanup, no warning out (stdout is likely closed.)
 		// Don't close the terminal with the clusterio master in it.
 		process.exit(1);
 	});
 
-	await fs.ensureDir(masterConfig.get('master.database_directory'));
+	await fs.ensureDir(masterConfig.get("master.database_directory"));
 
-	db.slaves = await loadMap(masterConfig.get('master.database_directory'), "slaves.json");
-	db.instances = await loadInstances(masterConfig.get('master.database_directory'), "instances.json");
+	db.slaves = await loadMap(masterConfig.get("master.database_directory"), "slaves.json");
+	db.instances = await loadInstances(masterConfig.get("master.database_directory"), "instances.json");
 	await loadUsers(masterConfig.get("master.database_directory"), "users.json");
 
 	// Make sure we're actually going to listen on a port
-	let httpPort = masterConfig.get('master.http_port');
-	let httpsPort = masterConfig.get('master.https_port');
+	let httpPort = masterConfig.get("master.http_port");
+	let httpsPort = masterConfig.get("master.https_port");
 	if (!httpPort && !httpsPort) {
 		console.error("Error: at least one of http_port and https_port must be configured");
 		process.exit(1);
 	}
 
-	let tls_cert = masterConfig.get('master.tls_certificate');
-	let tls_key = masterConfig.get('master.tls_private_key');
+	let tls_cert = masterConfig.get("master.tls_certificate");
+	let tls_key = masterConfig.get("master.tls_private_key");
 	// Create a self signed certificate if the certificate files doesn't exist
 	if (httpsPort && !await fs.exists(tls_cert) && !await fs.exists(tls_key)) {
 		await generateSSLcert({
@@ -1623,8 +1648,8 @@ async function startServer() {
 
 		httpsServer = require("https").createServer({
 			key: privateKey,
-			cert: certificate
-		}, app)
+			cert: certificate,
+		}, app);
 		await listen(httpsServer, httpsPort);
 		console.log("Listening for HTTPS on port %s...", httpsServer.address().port);
 	}
@@ -1641,7 +1666,7 @@ module.exports = {
 	_ControlConnection: ControlConnection,
 	_slaveConnections: slaveConnections,
 	_SlaveConnection: SlaveConnection,
-}
+};
 
 if (module === require.main) {
 	console.warn(`
diff --git a/package.json b/package.json
index fc2842fb..ee0d7b5c 100644
--- a/package.json
+++ b/package.json
@@ -10,6 +10,7 @@
     "cover": "nyc npm test",
     "fast-cover": "FAST_TEST=y nyc npm test",
     "ci-cover": "nyc --reporter=lcovonly npm run-script test",
+    "lint": "eslint \"*.js\" lib plugins test",
     "docs": "jsdoc --configure docs/jsdoc.json",
     "install": "node lib/npmPostinstall",
     "bundle-dependencies": "bundle-dependencies"
@@ -70,6 +71,7 @@
     "yargs": "^14.2.0"
   },
   "devDependencies": {
+    "eslint": "^7.2.0",
     "html5-validator": "^1.2.1",
     "jsdoc": "^3.6.3",
     "klaw": "^3.0.0",
diff --git a/plugins/global_chat/info.js b/plugins/global_chat/info.js
index 228bd554..69764974 100644
--- a/plugins/global_chat/info.js
+++ b/plugins/global_chat/info.js
@@ -1,3 +1,4 @@
+"use strict";
 let link = require("lib/link");
 let plugin = require("lib/plugin");
 
@@ -10,14 +11,14 @@ module.exports = {
 
 	messages: {
 		chat: new link.Event({
-			type: 'global_chat:chat',
-			links: ['instance-slave', 'slave-master', 'master-slave', 'slave-instance'],
-			forwardTo: 'master',
-			broadcastTo: 'instance',
+			type: "global_chat:chat",
+			links: ["instance-slave", "slave-master", "master-slave", "slave-instance"],
+			forwardTo: "master",
+			broadcastTo: "instance",
 			eventProperties: {
 				"instance_name": { type: "string" },
 				"content": { type: "string" },
 			},
 		}),
 	},
-}
+};
diff --git a/plugins/global_chat/instance.js b/plugins/global_chat/instance.js
index cf6cfbee..5cb2dadb 100644
--- a/plugins/global_chat/instance.js
+++ b/plugins/global_chat/instance.js
@@ -1,12 +1,16 @@
 /**
  * @module
  */
+"use strict";
 const plugin = require("lib/plugin");
 const luaTools = require("lib/luaTools");
 
 
 /**
  * Removes gps and train tags from messags
+ *
+ * @param {string} content - string to strip tags from.
+ * @returns {string} stripped string.
  */
 function removeTags(content) {
 	return content.replace(/(\[gps=-?\d+,-?\d+\]|\[train=\d+\])/g, "");
@@ -57,4 +61,4 @@ module.exports = {
 
 	// For testing only
 	_removeTags: removeTags,
-}
+};
diff --git a/plugins/global_chat/test/plugin.js b/plugins/global_chat/test/plugin.js
index 1652282e..7576a9b6 100644
--- a/plugins/global_chat/test/plugin.js
+++ b/plugins/global_chat/test/plugin.js
@@ -1,9 +1,10 @@
-const assert = require('assert').strict;
+"use strict";
+const assert = require("assert").strict;
 
-const mock = require('../../../test/mock');
-const lines = require('../../../test/lib/factorio/lines');
-const instance = require('../instance');
-const info = require('../info');
+const mock = require("../../../test/mock");
+const lines = require("../../../test/lib/factorio/lines");
+const instance = require("../instance");
+const info = require("../info");
 
 
 describe("global_chat plugin", function() {
@@ -62,6 +63,6 @@ describe("global_chat plugin", function() {
 				}
 				assert(count > 0, "no lines were tested");
 			});
-		})
+		});
 	});
 });
diff --git a/plugins/research_sync/info.js b/plugins/research_sync/info.js
index 2e184014..c9d85316 100644
--- a/plugins/research_sync/info.js
+++ b/plugins/research_sync/info.js
@@ -1,3 +1,4 @@
+"use strict";
 const link = require("lib/link");
 
 
@@ -13,7 +14,7 @@ const technologies = {
 			{ type: "integer" },
 			{ type: ["null", "number"] },
 			{ type: "boolean" },
-		]
+		],
 	},
 };
 
@@ -77,4 +78,4 @@ module.exports = {
 			},
 		}),
 	},
-}
+};
diff --git a/plugins/research_sync/instance.js b/plugins/research_sync/instance.js
index ffbeb3a0..d87b0b29 100644
--- a/plugins/research_sync/instance.js
+++ b/plugins/research_sync/instance.js
@@ -1,3 +1,4 @@
+"use strict";
 const needle = require("needle");
 
 const plugin = require("lib/plugin");
@@ -5,8 +6,8 @@ const luaTools = require("lib/luaTools");
 
 
 function unexpectedError(err) {
-	console.log("Unexpected error in research_sync")
-	console.log("---------------------------------")
+	console.log("Unexpected error in research_sync");
+	console.log("---------------------------------");
 	console.log(err);
 }
 
@@ -78,4 +79,4 @@ class InstancePlugin extends plugin.BaseInstancePlugin {
 
 module.exports = {
 	InstancePlugin,
-}
+};
diff --git a/plugins/research_sync/master.js b/plugins/research_sync/master.js
index fa114503..a6f0cbd4 100644
--- a/plugins/research_sync/master.js
+++ b/plugins/research_sync/master.js
@@ -1,3 +1,4 @@
+"use strict";
 const fs = require("fs-extra");
 const path = require("path");
 
@@ -38,7 +39,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 	}
 
 	broadcastProgress() {
-		let techs = []
+		let techs = [];
 		for (let name of this.progressToBroadcast) {
 			let tech = this.technologies.get(name);
 			if (tech.progress) {
@@ -58,7 +59,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 		let tech = this.technologies.get(name);
 		if (!tech) {
 			tech = { level, progress: 0, researched: false };
-			this.technologies.set(name, tech)
+			this.technologies.set(name, tech);
 
 		// Ignore contribution to already researched technologies
 		} else if (tech.level > level || tech.level === level && tech.researched) {
@@ -96,7 +97,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 		let tech = this.technologies.get(name);
 		if (!tech || tech.level <= level) {
 			this.progressToBroadcast.delete(name);
-			this.technologies.set(name, { level, progress: null, researched: true })
+			this.technologies.set(name, { level, progress: null, researched: true });
 		}
 	}
 
@@ -111,7 +112,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 		}
 
 		for (let instanceTech of message.data.technologies) {
-			let [name, level, progress, researched] =  instanceTech;
+			let [name, level, progress, researched] = instanceTech;
 			let tech = this.technologies.get(name);
 			if (!tech) {
 				this.technologies.set(name, { level, progress, researched });
@@ -151,10 +152,10 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 
 		let technologies = [];
 		for (let [name, tech] of this.technologies) {
-			technologies.push([ name, tech.level, tech.progress, tech.researched ])
+			technologies.push([name, tech.level, tech.progress, tech.researched]);
 		}
 
-		return { technologies }
+		return { technologies };
 	}
 }
 
@@ -183,5 +184,5 @@ async function saveTechnologies(masterConfig, technologies) {
 
 
 module.exports = {
-	MasterPlugin
-}
+	MasterPlugin,
+};
diff --git a/plugins/research_sync/test/missing.js b/plugins/research_sync/test/missing.js
index c0b5b5ab..4cab8cce 100644
--- a/plugins/research_sync/test/missing.js
+++ b/plugins/research_sync/test/missing.js
@@ -1,5 +1,6 @@
 // These are libraries that does not have any units test, they are
 // required here in order to track coverage for them.
 
-require('../instance');
-require('../master');
+"use strict";
+require("../instance");
+require("../master");
diff --git a/plugins/statistics_exporter/info.js b/plugins/statistics_exporter/info.js
index a1bf60da..ca83b9b5 100644
--- a/plugins/statistics_exporter/info.js
+++ b/plugins/statistics_exporter/info.js
@@ -1,3 +1,4 @@
+"use strict";
 let link = require("lib/link");
 
 module.exports = {
@@ -6,4 +7,4 @@ module.exports = {
 	description: "Exports statistics to Prometheus",
 	version: "2.0.0-alpha",
 	instanceEntrypoint: "instance",
-}
+};
diff --git a/plugins/statistics_exporter/instance.js b/plugins/statistics_exporter/instance.js
index 4ca365ad..b76ae99b 100644
--- a/plugins/statistics_exporter/instance.js
+++ b/plugins/statistics_exporter/instance.js
@@ -1,28 +1,29 @@
-const plugin = require('lib/plugin');
-const { Gauge } = require('lib/prometheus');
+"use strict";
+const plugin = require("lib/plugin");
+const { Gauge } = require("lib/prometheus");
 
 
 const instancePlayerCount = new Gauge(
 	"clusterio_statistics_exporter_instance_player_count", "Amount of players connected to this cluster",
-	{ labels: ['instance_id'] }
+	{ labels: ["instance_id"] }
 );
 const instanceGameTicksTotal = new Gauge(
 	"clusterio_statistics_exporter_instance_game_ticks_total", "Game tick an instance has progressed to",
-	{ labels: ['instance_id'] }
+	{ labels: ["instance_id"] }
 );
 const instanceForceFlowStatistics = new Gauge(
 	"clusterio_statistics_exporter_instance_force_flow_statistics", "Items/fluids/enemies/buildings produced/built/killed by a force",
-	{ labels: ['instance_id', 'force', 'statistic', 'direction', 'name'] },
+	{ labels: ["instance_id", "force", "statistic", "direction", "name"] },
 );
 const instanceGameFlowStatistics = new Gauge(
 	"clusterio_statistics_exporter_instance_game_flow_statistics", "Pollution produced/consumed in the game",
-	{ labels: ['instance_id', 'statistic', 'direction', 'name'] },
+	{ labels: ["instance_id", "statistic", "direction", "name"] },
 );
 
 
 class InstancePlugin extends plugin.BaseInstancePlugin {
 	async onMetrics() {
-		let string = await this.instance.server.sendRcon('/sc statistics_exporter.export()');
+		let string = await this.instance.server.sendRcon("/sc statistics_exporter.export()");
 		let stats;
 		try {
 			stats = JSON.parse(string);
@@ -64,4 +65,4 @@ module.exports = {
 	_instanceGameTicksTotal: instanceGameTicksTotal,
 	_instanceForceFlowStatistics: instanceForceFlowStatistics,
 	_instanceGameFlowStatistics: instanceGameFlowStatistics,
-}
+};
diff --git a/plugins/statistics_exporter/test/plugin.js b/plugins/statistics_exporter/test/plugin.js
index 2112a441..52d18595 100644
--- a/plugins/statistics_exporter/test/plugin.js
+++ b/plugins/statistics_exporter/test/plugin.js
@@ -1,8 +1,9 @@
-const assert = require('assert').strict;
+"use strict";
+const assert = require("assert").strict;
 
-const mock = require('../../../test/mock');
-const instance = require('../instance');
-const info = require('../info');
+const mock = require("../../../test/mock");
+const instance = require("../instance");
+const info = require("../info");
 
 
 describe("statistics_exporter plugin", function() {
@@ -16,42 +17,42 @@ describe("statistics_exporter plugin", function() {
 		describe(".onMetrics()", function() {
 			it("should record statistics", async function() {
 				instancePlugin.instance.server.rconCommandResults.set(
-					'/sc statistics_exporter.export()',
+					"/sc statistics_exporter.export()",
 					JSON.stringify({
 						game_tick: 100,
 						player_count: 3,
 						force_flow_statistics: {
 							player: {
 								item_production_statistics: {
-									input: { "inserter": 10, },
-									output: { "iron-plate": 24, }
+									input: { "inserter": 10 },
+									output: { "iron-plate": 24 },
 								},
-							}
+							},
 						},
 						game_flow_statistics: {
 							pollution_statistics: {
 								input: { "boiler": 2000 },
 								output: { "tree-proxy": 560 },
-							}
+							},
 						},
 					})
 				);
 
 				await instancePlugin.onMetrics();
 
-				assert.equal(instance._instancePlayerCount.labels('7357').get(), 3);
-				assert.equal(instance._instanceGameTicksTotal.labels('7357').get(), 100);
+				assert.equal(instance._instancePlayerCount.labels("7357").get(), 3);
+				assert.equal(instance._instanceGameTicksTotal.labels("7357").get(), 100);
 				assert.equal(instance._instanceForceFlowStatistics.labels(
-					'7357', 'player', 'item_production_statistics', 'input', 'inserter').get(),
+					"7357", "player", "item_production_statistics", "input", "inserter").get(),
 				10);
 				assert.equal(instance._instanceGameFlowStatistics.labels(
-					'7357', 'pollution_statistics', 'input', 'boiler').get(),
+					"7357", "pollution_statistics", "input", "boiler").get(),
 				2000);
 			});
 			it("should pass on JSON parse errors", async function() {
-				let string = 'An error occured\n';
+				let string = "An error occured\n";
 				instancePlugin.instance.server.rconCommandResults.set(
-					'/sc statistics_exporter.export()', string
+					"/sc statistics_exporter.export()", string
 				);
 
 				let errorMessage;
diff --git a/plugins/subspace_storage/dole.js b/plugins/subspace_storage/dole.js
index f7ed8dc2..fe06bb3a 100644
--- a/plugins/subspace_storage/dole.js
+++ b/plugins/subspace_storage/dole.js
@@ -1,4 +1,5 @@
-const doleNN = require("./dole_nn_base")
+"use strict";
+const doleNN = require("./dole_nn_base");
 
 const prometheus = require("lib/prometheus");
 
@@ -15,31 +16,32 @@ const prometheusDoleFactorGauge = new prometheus.Gauge(
 );
 
 class neuralDole {
-    
-    getRequestStats(itemname,samples)
-    {
-        var sum=0;
-        samples=Math.min(samples,(this.stats[itemname] || []).length-1);
-        if (samples<1) return 0.1;
-        for (var i = 1; i <= samples; i++) {
-            sum+=this.stats[itemname][i].req;
-        }
-        if (sum==0) return 0.1;
-        return sum/samples;
-    }
-    
-    constructor({
-		items
-    }){
-        // Set some storage variables for the dole divider
-		this.items = items
-		this.itemsLastTick = new Map(items._items)
-        this.dole = {}
-        this.carry = {}
-        this.lastRequest = {}
-        this.stats=[]
-		this.debt= {}
+
+	getRequestStats(itemname,samples)
+	{
+		var sum=0;
+		samples=Math.min(samples,(this.stats[itemname] || []).length-1);
+		if (samples<1) return 0.1;
+		for (var i = 1; i <= samples; i++) {
+			sum+=this.stats[itemname][i].req;
+		}
+		if (sum==0) return 0.1;
+		return sum/samples;
 	}
+
+	constructor({
+		items,
+	}){
+		// Set some storage variables for the dole divider
+		this.items = items;
+		this.itemsLastTick = new Map(items._items);
+		this.dole = {};
+		this.carry = {};
+		this.lastRequest = {};
+		this.stats=[];
+		this.debt= {};
+	}
+
 	doMagic() {
 		for (let [name, count] of this.items._items) {
 			let magicData = doleNN.Tick(
@@ -47,84 +49,85 @@ class neuralDole {
 				this.dole[name],
 				this.itemsLastTick.get(name),
 				this.getRequestStats(name,5)
-			)
-			this.stats[name]=this.stats[name] || []
-			this.stats[name].unshift({req:0,given:0});//stats[name][0] is the one we currently collect
+			);
+			this.stats[name]=this.stats[name] || [];
+			this.stats[name].unshift({ req: 0, given: 0 });//stats[name][0] is the one we currently collect
 			if (this.stats[name].length>10) this.stats[name].pop();//remove if too many samples in stats
 
-			this.dole[name] = magicData[0]
+			this.dole[name] = magicData[0];
 			// DONE handle magicData[1] for graphing for our users
 			prometheusNNDoleGauge.labels(name).set(magicData[1] || 0);
 		}
-		this.itemsLastTick = new Map(this.items._items)
-    }
-    divider(object) {
-        let magicData = doleNN.Dose(
-            object.count, // numReq
+		this.itemsLastTick = new Map(this.items._items);
+	}
+
+	divider(object) {
+		let magicData = doleNN.Dose(
+			object.count, // numReq
 			this.items.getItemCount(object.name),
 			this.itemsLastTick.get(object.name) || 0,
-            this.dole[object.name],
-            this.carry[object.name+" "+object.instanceID] || 0,
-            this.lastRequest[object.name+"_"+object.instanceID+"_"+object.instanceName] || 0,
-            this.getRequestStats(object.name,5),
+			this.dole[object.name],
+			this.carry[object.name+" "+object.instanceID] || 0,
+			this.lastRequest[object.name+"_"+object.instanceID+"_"+object.instanceName] || 0,
+			this.getRequestStats(object.name,5),
 			this.debt[object.name+" "+object.instanceID] || 0
-        )
-        if ((this.stats[object.name] || []).length>0)
-        {
-            this.stats[object.name][0].req+=Number(object.count);
-            this.stats[object.name][0].given+=Number(magicData[0]);
-        }
-        this.lastRequest[object.name+"_"+object.instanceID+"_"+object.instanceName] = object.count
-        //0.Number of items to give in that dose
-        //1.New dole for item X
-        //2.New carry for item X slave Y
-        this.dole[object.name] = magicData[1]
-        this.carry[object.name+" "+object.instanceID] = magicData[2]
-		this.debt[object.name+" "+object.instanceID] = magicData[3]
+		);
+		if ((this.stats[object.name] || []).length>0)
+		{
+			this.stats[object.name][0].req+=Number(object.count);
+			this.stats[object.name][0].given+=Number(magicData[0]);
+		}
+		this.lastRequest[object.name+"_"+object.instanceID+"_"+object.instanceName] = object.count;
+		//0.Number of items to give in that dose
+		//1.New dole for item X
+		//2.New carry for item X slave Y
+		this.dole[object.name] = magicData[1];
+		this.carry[object.name+" "+object.instanceID] = magicData[2];
+		this.debt[object.name+" "+object.instanceID] = magicData[3];
 
 		// Remove item from DB and send it
 		this.items.removeItem(object.name, magicData[0]);
 
 		return magicData[0];
-    }
+	}
 }
 
 // If the server regularly can't fulfill requests, this number grows until it can. Then it slowly shrinks back down.
 let _doleDivisionFactor = {};
 function doleDivider({
-    object,
+	object,
 	items,
 	logItemTransfers,
 }){
 	let itemCount = items.getItemCount(object.name);
-    const doleDivisionRetardation = 10; //lower rates will equal more dramatic swings
-    const maxDoleDivision = 250; //a higher cap will divide the store more ways, but will take longer to recover as supplies increase
-    
-    const originalCount = Number(object.count) || 0;
-    object.count /= ((_doleDivisionFactor[object.name]||0)+doleDivisionRetardation)/doleDivisionRetardation;
-    object.count = Math.round(object.count);
+	const doleDivisionRetardation = 10; //lower rates will equal more dramatic swings
+	const maxDoleDivision = 250; //a higher cap will divide the store more ways, but will take longer to recover as supplies increase
+
+	const originalCount = Number(object.count) || 0;
+	object.count /= ((_doleDivisionFactor[object.name]||0)+doleDivisionRetardation)/doleDivisionRetardation;
+	object.count = Math.round(object.count);
 	if (logItemTransfers) {
-		console.info(`Serving ${object.count}/${originalCount} ${object.name} from ${itemCount} ${object.name} with dole division factor ${(_doleDivisionFactor[object.name]||0)} (real=${((_doleDivisionFactor[object.name]||0)+doleDivisionRetardation)/doleDivisionRetardation}), item is ${itemCount > object.count?'stocked':'short'}.`);
+		console.info(`Serving ${object.count}/${originalCount} ${object.name} from ${itemCount} ${object.name} with dole division factor ${(_doleDivisionFactor[object.name]||0)} (real=${((_doleDivisionFactor[object.name]||0)+doleDivisionRetardation)/doleDivisionRetardation}), item is ${itemCount > object.count?"stocked":"short"}.`);
 	}
 
 	// Update existing items if item name already exists
 	if (itemCount > object.count) {
-        //If successful, increase dole
-        _doleDivisionFactor[object.name] = Math.max((_doleDivisionFactor[object.name]||0)||1, 1) - 1;
-		items.removeItem(object.name, object.count)
+		//If successful, increase dole
+		_doleDivisionFactor[object.name] = Math.max((_doleDivisionFactor[object.name]||0)||1, 1) - 1;
+		items.removeItem(object.name, object.count);
 
-        prometheusDoleFactorGauge.labels(object.name).set(_doleDivisionFactor[object.name] || 0);
-        return object.count;
-    } else {
-        // if we didn't have enough, attempt giving out a smaller amount next time
-        _doleDivisionFactor[object.name] = Math.min(maxDoleDivision, Math.max((_doleDivisionFactor[object.name]||0)||1, 1) * 2);
-        prometheusDoleFactorGauge.labels(object.name).set(_doleDivisionFactor[object.name] || 0);
-        return 0;
-        //console.log('failure out of ' + object.name + " | " + object.count + " from " + object.instanceID + " ("+object.instanceName+")");
-    }
+		prometheusDoleFactorGauge.labels(object.name).set(_doleDivisionFactor[object.name] || 0);
+		return object.count;
+	} else {
+		// if we didn't have enough, attempt giving out a smaller amount next time
+		_doleDivisionFactor[object.name] = Math.min(maxDoleDivision, Math.max((_doleDivisionFactor[object.name]||0)||1, 1) * 2);
+		prometheusDoleFactorGauge.labels(object.name).set(_doleDivisionFactor[object.name] || 0);
+		return 0;
+		//console.log('failure out of ' + object.name + " | " + object.count + " from " + object.instanceID + " ("+object.instanceName+")");
+	}
 }
 
 module.exports = {
-    doleDivider,
-    neuralDole
-}
\ No newline at end of file
+	doleDivider,
+	neuralDole,
+};
diff --git a/plugins/subspace_storage/dole_nn_base.js b/plugins/subspace_storage/dole_nn_base.js
index ba00188c..dc978ebc 100644
--- a/plugins/subspace_storage/dole_nn_base.js
+++ b/plugins/subspace_storage/dole_nn_base.js
@@ -1,5 +1,6 @@
 //Sigmoids...
 
+"use strict";
 function sigmoid0(x)
 {
 	return x/(1+Math.abs(x));
@@ -7,17 +8,17 @@ function sigmoid0(x)
 function sigmoid1(x)
 {
 	if (x>=0.0) {
-		return 1.0
+		return 1.0;
 	} else {
-		return 0.0
+		return 0.0;
 	}
 }
 function sigmoid2(x)
 {
 	if (x>=0.0){
-		return x
+		return x;
 	} else {
-		return 0.0
+		return 0.0;
 	}
 }
 function sigmoid3(x)
@@ -46,7 +47,7 @@ function Dose(numreq,instore,store_last_tick,dole,carry,prev_req,numreq_total_ad
 	instore=Number(instore);
 	var instore_adj=instore;
 	if (instore_adj==0) instore_adj=0.1;
-	
+
 	var b=Math.trunc(prev_req/instore_adj*numreq);
 	var inp1=[numreq,instore_adj,store_last_tick/numreq,dole,carry];//0..4
 	var inp2=[prev_req/numreq,numreq/numreq_total_adj,store_last_tick/numreq_total_adj,prev_req/instore_adj,b,numreq_total_adj,store_last_tick,debt];//5..12
@@ -54,30 +55,30 @@ function Dose(numreq,instore,store_last_tick,dole,carry,prev_req,numreq_total_ad
 	var internal=new Array(20).fill(0);
 	var outputs=[0,0,0,0];
 	//NN: Please don't touch :), code is generated
-	
-outputs[0]=inputs[7]*0.8058582544;
-outputs[0]=sigmoid2(outputs[0]);
-outputs[1]=sigmoid0(outputs[1]);
-outputs[2]=sigmoid0(outputs[2]);
-outputs[3]=inputs[6]*0.2294657379;
-outputs[3]=sigmoid0(outputs[3]);
+
+	outputs[0]=inputs[7]*0.8058582544;
+	outputs[0]=sigmoid2(outputs[0]);
+	outputs[1]=sigmoid0(outputs[1]);
+	outputs[2]=sigmoid0(outputs[2]);
+	outputs[3]=inputs[6]*0.2294657379;
+	outputs[3]=sigmoid0(outputs[3]);
 
 	debt=debt || 0;
 	if (outputs[0]>0.99) outputs[0]=1.0;
-	
+
 	var res1=Number(outputs[0])*numreq+outputs[3]+debt;
 	var res_capped=Math.round(res1);
-	
+
 	if (res_capped>numreq) res_capped=numreq;
 	if (res_capped>instore) res_capped=instore;
 	if (res_capped<0) res_capped=0;
-	
+
 	res1=res1 || 0;
 	res_capped=res_capped || 0;//Safeguard against wrong values
 	debt=res1-res_capped;
 	debt_cap=Math.round(numreq*1.5)+5;
 	if (debt>debt_cap) debt=debt_cap;
-	
+
 	carry=sigmoid0(outputs[2]*carry+outputs[0]) || 0;
 	return [res_capped,dole+outputs[1],carry,debt];
 }
@@ -101,19 +102,19 @@ function Tick(instore,dole,store_last_tick,numreq_total_adj)
 	var internal=new Array(10).fill(0);
 	var outputs=[0,0];
 	//NN: Please don't touch :), code is generated
-	
-outputs[0]=inputs[3]*0.9364774823;
-outputs[0]=outputs[0]*1.0*0.4590721726;
-outputs[0]=sigmoid2(outputs[0]);
-outputs[1]=outputs[0]*1.828422785;
-outputs[1]=sigmoid3(outputs[1]);
+
+	outputs[0]=inputs[3]*0.9364774823;
+	outputs[0]=outputs[0]*0.4590721726;
+	outputs[0]=sigmoid2(outputs[0]);
+	outputs[1]=outputs[0]*1.828422785;
+	outputs[1]=sigmoid3(outputs[1]);
 
 	avg=outputs[1];
 	if (numreq_total_adj<0.11) avg=1;//When no item's are requested, result is 0.1 ; In that case there is no deficit, so return 1 = 100% demand fulfilled
 	if (avg>1) avg=1;
 	if (avg<0) avg=0;
-	
+
 	return [sigmoid0(outputs[0]),avg];
 }
 
-module.exports = {Dose,Tick}
\ No newline at end of file
+module.exports = { Dose,Tick };
diff --git a/plugins/subspace_storage/info.js b/plugins/subspace_storage/info.js
index dbbfc683..028162e8 100644
--- a/plugins/subspace_storage/info.js
+++ b/plugins/subspace_storage/info.js
@@ -1,3 +1,4 @@
+"use strict";
 const link = require("lib/link");
 const config = require("lib/config");
 
@@ -50,7 +51,7 @@ const items = {
 			{ type: "integer" },
 		],
 	},
-}
+};
 
 module.exports = {
 	name: "subspace_storage",
@@ -103,4 +104,4 @@ module.exports = {
 			},
 		}),
 	},
-}
+};
diff --git a/plugins/subspace_storage/instance.js b/plugins/subspace_storage/instance.js
index 7be30d1b..53ca3571 100644
--- a/plugins/subspace_storage/instance.js
+++ b/plugins/subspace_storage/instance.js
@@ -1,11 +1,12 @@
+"use strict";
 const fs = require("fs-extra");
 
 const plugin = require("lib/plugin");
 const luaTools = require("lib/luaTools");
 
 function unexpectedError(err) {
-	console.log("Unexpected error in subspace_storage")
-	console.log("------------------------------------")
+	console.log("Unexpected error in subspace_storage");
+	console.log("------------------------------------");
 	console.log(err);
 }
 
@@ -44,7 +45,7 @@ class InstancePlugin extends plugin.BaseInstancePlugin {
 		});
 
 		if (this.instance.config.get("subspace_storage.log_item_transfers")) {
-			console.log("Exported the following to master:")
+			console.log("Exported the following to master:");
 			console.log(items);
 		}
 	}
@@ -62,7 +63,7 @@ class InstancePlugin extends plugin.BaseInstancePlugin {
 		}
 
 		if (this.instance.config.get("subspace_storage.log_item_transfers")) {
-			console.log("Imported following from master:")
+			console.log("Imported following from master:");
 			console.log(response.items);
 		}
 
diff --git a/plugins/subspace_storage/master.js b/plugins/subspace_storage/master.js
index b688fb14..9a6bdab5 100644
--- a/plugins/subspace_storage/master.js
+++ b/plugins/subspace_storage/master.js
@@ -47,8 +47,8 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 		this.itemsLastUpdate = new Map(this.items._items.entries());
 		this.autosaveId = setInterval(() => {
 			saveDatabase(this.master.config, this.items).catch(err => {
-				console.log("Unexpected error autosaving items in subspace_storage")
-				console.log("-----------------------------------------------------")
+				console.log("Unexpected error autosaving items in subspace_storage");
+				console.log("-----------------------------------------------------");
 				console.log(err);
 			});
 		}, this.master.config.get("subspace_storage.autosave_interval") * 1000);
@@ -56,7 +56,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 		this.neuralDole = new dole.neuralDole({ items: this.items });
 		this.doleMagicId = setInterval(() => {
 			if (this.master.config.get("subspace_storage.division_method") === "neural_dole") {
-				this.neuralDole.doMagic()
+				this.neuralDole.doMagic();
 			}
 		}, 1000);
 
@@ -97,7 +97,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 		this.updateStorage();
 
 		if (this.master.config.get("subspace_storage.log_item_transfers")) {
-			console.log(`Imported the following from ${message.data.instance_id}:`)
+			console.log(`Imported the following from ${message.data.instance_id}:`);
 			console.log(message.data.items);
 		}
 	}
@@ -136,7 +136,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 			} else if (method === "dole") {
 				for (let item of message.data.items) {
 					let count = dole.doleDivider({
-						object: { name: item[0], count: item[1], instanceId, instanceName},
+						object: { name: item[0], count: item[1], instanceId, instanceName },
 						items: this.items,
 						logItemTransfers: this.master.config.get("subspace_storage.log_item_transfers"),
 					});
@@ -166,7 +166,7 @@ class MasterPlugin extends plugin.BaseMasterPlugin {
 
 		return {
 			items: itemsRemoved,
-		}
+		};
 	}
 
 	onMetrics() {
diff --git a/plugins/subspace_storage/routes.js b/plugins/subspace_storage/routes.js
index 301cc371..cffa5c54 100644
--- a/plugins/subspace_storage/routes.js
+++ b/plugins/subspace_storage/routes.js
@@ -1,3 +1,4 @@
+"use strict";
 const express = require("express");
 const path = require("path");
 
@@ -53,4 +54,4 @@ function addApiRoutes(app, items, endpointHitCounter) {
 module.exports = {
 	addWebRoutes,
 	addApiRoutes,
-}
+};
diff --git a/plugins/subspace_storage/static/storage.js b/plugins/subspace_storage/static/storage.js
index 8948ae9c..a2f9157d 100644
--- a/plugins/subspace_storage/static/storage.js
+++ b/plugins/subspace_storage/static/storage.js
@@ -1,35 +1,36 @@
 // function to draw data we recieve from ajax requests
+"use strict";
 _lastData = [];
 function drawcontents(data) {
 	data = data || _lastData; //Cache data so we can drawcontents without waiting for the server, for the search box.
 	_lastData = data;
 
-        // allow searching for multiple criteria separated by space
-        var searchArgs = document.querySelector("#search").value;
-        searchArgs = searchArgs.trim();
-        searchArgs = '(' + searchArgs.replace(/ +/g,")|(") + ')';
-        const search = new RegExp(searchArgs, 'i');
-        data = data.filter(function(item) {
+	// allow searching for multiple criteria separated by space
+	var searchArgs = document.querySelector("#search").value;
+	searchArgs = searchArgs.trim();
+	searchArgs = "(" + searchArgs.replace(/ +/g,")|(") + ")";
+	const search = new RegExp(searchArgs, "i");
+	data = data.filter(function(item) {
 		return search.test(item.name);
-	})
-	
+	});
+
 	sortByKey(data, "count");
-	
+
 	const table = document.querySelector("#contents tbody"); //tables have tbody inserted automatically
 	const rows = table.children;
-	
+
 	//update existing rows or create new ones
 	data.forEach(function(item, i) {
 		// format count to have .s in it for large number readability (1,000,000)
 		item.count = item.count.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
-		
+
 		let row = rows[i];
 		if(!row) {
-			row = document.createElement('tr');
+			row = document.createElement("tr");
 			row.innerHTML = "<td><div></div></td><td class=name></td><td class=count></td>";
 			table.appendChild(row);
 		}
-		
+
 		const itemIcon = row.querySelector("div");
 		const iconClass = getItemIconClass(item.name);
 		if (itemIcon.getAttribute("class") !== iconClass) {
@@ -51,17 +52,17 @@ function drawcontents(data) {
 			}
 		}
 
-		const name = row.querySelector('.name');
+		const name = row.querySelector(".name");
 		if(name.textContent !== localeName) {
 			name.textContent = localeName;
 		}
-		
-		const count = row.querySelector('.count');
-		if(count.textContent !== ''+item.count) {
+
+		const count = row.querySelector(".count");
+		if(count.textContent !== String(item.count)) {
 			count.textContent = item.count;
 		}
 	});
-	
+
 	//remove excess rows, for example, after filtering
 	while (data.length < rows.length) {
 		table.removeChild(rows[data.length]);
@@ -76,7 +77,7 @@ function updateInventory() {
 			let data = JSON.parse(xmlhttp.responseText);
 			drawcontents(data);
 		}
-	}
+	};
 	xmlhttp.open("GET", `${root}api/inventory`, true);
 	xmlhttp.send();
 }
@@ -88,11 +89,11 @@ if(JSON.parse(localStorage.settings)["Periodically update storage screen"]) {
 
 // function to sort arrays of objects after a keys value
 function sortByKey(array, key) {
-    array.sort(function(a, b) {
-        return b[key] - a[key];
-    });
+	array.sort(function(a, b) {
+		return b[key] - a[key];
+	});
 }
 
-document.querySelector("#search").addEventListener('input', function() {
+document.querySelector("#search").addEventListener("input", function() {
 	drawcontents();
 });
diff --git a/plugins/subspace_storage/test/missing.js b/plugins/subspace_storage/test/missing.js
index 7eadd460..0389e0e5 100644
--- a/plugins/subspace_storage/test/missing.js
+++ b/plugins/subspace_storage/test/missing.js
@@ -1,7 +1,8 @@
 // These are libraries that does not have any units test, they are
 // required here in order to track coverage for them.
 
-require('../instance');
-require('../master');
-require('../dole');
-require('../dole_nn_base');
+"use strict";
+require("../instance");
+require("../master");
+require("../dole");
+require("../dole_nn_base");
diff --git a/plugins/subspace_storage/test/routes.js b/plugins/subspace_storage/test/routes.js
index 3a860681..cd6c9366 100644
--- a/plugins/subspace_storage/test/routes.js
+++ b/plugins/subspace_storage/test/routes.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 
 const routes = require("../routes");
@@ -18,7 +19,7 @@ describe("subspace_storage endpoints", function() {
 			inventory.forEach(itemStack => {
 				if(itemStack.name == "steel-plate" && itemStack.count >= 20) contains20SteelPlate = true;
 			});
-			assert(contains20SteelPlate, "Please ensure there are at least 20 steel plate in the inventory")
+			assert(contains20SteelPlate, "Please ensure there are at least 20 steel plate in the inventory");
 		});
 	});
 });
diff --git a/routes.js b/routes.js
index efd330b0..1b3c7c92 100644
--- a/routes.js
+++ b/routes.js
@@ -1,3 +1,4 @@
+"use strict";
 module.exports = function(app) {
 	app.get("/", function(req, res) {
 		res.render("index");
@@ -11,4 +12,4 @@ module.exports = function(app) {
 	app.get("/nodeDetails", function(req, res) {
 		res.render("nodeDetails");
 	});
-};
\ No newline at end of file
+};
diff --git a/slave.js b/slave.js
index 8e949460..41466a2f 100644
--- a/slave.js
+++ b/slave.js
@@ -10,8 +10,9 @@
  * @example
  * node slave run
  */
-const fs = require('fs-extra');
-const path = require('path');
+"use strict";
+const fs = require("fs-extra");
+const path = require("path");
 const yargs = require("yargs");
 const events = require("events");
 const pidusage = require("pidusage");
@@ -22,14 +23,13 @@ const version = require("./package").version;
 
 // internal libraries
 const fileOps = require("lib/fileOps");
-const hashFile = require('lib/hash').hashFile;
 const factorio = require("lib/factorio");
 const link = require("lib/link");
 const plugin = require("lib/plugin");
 const errors = require("lib/errors");
-const prometheus = require('lib/prometheus');
-const luaTools = require('lib/luaTools');
-const config = require('lib/config');
+const prometheus = require("lib/prometheus");
+const luaTools = require("lib/luaTools");
+const config = require("lib/config");
 
 
 const instanceRconCommandsCounter = new prometheus.Counter(
@@ -69,7 +69,7 @@ function applyAsConfig(name) {
 		} catch (err) {
 			console.error(`Error applying server setting ${name}`, err);
 		}
-	}
+	};
 }
 
 const serverSettingsActions = {
@@ -87,7 +87,7 @@ const serverSettingsActions = {
 	"game_password": applyAsConfig("password"),
 	"require_user_verification": applyAsConfig("require-user-verification"),
 	"tags": applyAsConfig("tags"),
-	"visibility": async function action(server, value) {
+	"visibility": async (server, value) => {
 		for (let scope of ["lan", "public", "steam"]) {
 			try {
 				let enabled = Boolean(value[scope]);
@@ -104,7 +104,7 @@ const serverSettingsActions = {
  */
 class Instance extends link.Link{
 	constructor(slave, connector, dir, factorioDir, instanceConfig) {
-		super('instance', 'slave', connector);
+		super("instance", "slave", connector);
 		link.attachAllMessages(this);
 		this._slave = slave;
 		this._dir = dir;
@@ -125,9 +125,9 @@ class Instance extends link.Link{
 
 		let serverOptions = {
 			version: this.config.get("factorio.version"),
-			gamePort: this.config.get('factorio.game_port'),
-			rconPort: this.config.get('factorio.rcon_port'),
-			rconPassword: this.config.get('factorio.rcon_password'),
+			gamePort: this.config.get("factorio.game_port"),
+			rconPort: this.config.get("factorio.rcon_port"),
+			rconPassword: this.config.get("factorio.rcon_password"),
 		};
 
 		this._running = false;
@@ -139,10 +139,10 @@ class Instance extends link.Link{
 		this.server.sendRcon = (...args) => {
 			instanceRconCommandsCounter.labels(String(this.config.get("instance.id"))).inc();
 			return originalSendRcon.call(this.server, ...args);
-		}
+		};
 
-		this.server.on('output', (output) => {
-			link.messages.instanceOutput.send(this, { instance_id: this.config.get("instance.id"), output })
+		this.server.on("output", (output) => {
+			link.messages.instanceOutput.send(this, { instance_id: this.config.get("instance.id"), output });
 
 			plugin.invokeHook(this.plugins, "onOutput", output);
 		});
@@ -181,7 +181,7 @@ class Instance extends link.Link{
 		for (let collector of prometheus.defaultRegistry.collectors) {
 			if (
 				collector instanceof prometheus.ValueCollector
-				&& collector.metric.labels.includes('instance_id')
+				&& collector.metric.labels.includes("instance_id")
 			) {
 				collector.removeAll({ instance_id: String(this.config.get("instance.id")) });
 			}
@@ -225,7 +225,7 @@ class Instance extends link.Link{
 			}
 		}
 
-		let plugins = {}
+		let plugins = {};
 		for (let [name, plugin] of this.plugins) {
 			plugins[name] = plugin.info.version;
 		}
@@ -239,7 +239,8 @@ class Instance extends link.Link{
 	 * entries from the given settings object.
 	 *
 	 * @param {Object} overrides - Server settings to override.
-	 * @returns server example settings with the given settings applied over it.
+	 * @returns {Object}
+	 *     server example settings with the given settings applied over it.
 	 */
 	async resolveServerSettings(overrides) {
 		let serverSettings = await this.server.exampleSettings();
@@ -275,13 +276,11 @@ class Instance extends link.Link{
 	 * Creates the neccessary files for starting up a new instance into the
 	 * provided instance directory.
 	 *
-	 * @param {Number} id -
-	 *     ID of the new instance.  Must be unique to the cluster.
 	 * @param {String} instanceDir -
 	 *     Directory to create the new instance into.
 	 * @param {String} factorioDir - Path to factorio installation.
 	 */
-	static async create(instanceConfig, instanceDir, factorioDir) {
+	static async create(instanceDir, factorioDir) {
 		console.log(`Clusterio | Creating ${instanceDir}`);
 		await fs.ensureDir(instanceDir);
 		await fs.ensureDir(path.join(instanceDir, "script-output"));
@@ -320,13 +319,13 @@ class Instance extends link.Link{
 		// Use latest save if no save was specified
 		if (saveName === null) {
 			saveName = await fileOps.getNewestFile(
-				this.path("saves"), (name) => !name.endsWith('.tmp.zip')
+				this.path("saves"), (name) => !name.endsWith(".tmp.zip")
 			);
 		}
 
 		// Create save if no save was found.
 		if (saveName === null) {
-			console.log("Clusterio | Creating new save")
+			console.log("Clusterio | Creating new save");
 			await this.server.create("world.zip");
 			saveName = "world.zip";
 		}
@@ -337,12 +336,12 @@ class Instance extends link.Link{
 		// Find plugin modules to patch in
 		let modules = new Map();
 		for (let [pluginName, plugin] of this.plugins) {
-			let modulePath = path.join('plugins', pluginName, 'module');
+			let modulePath = path.join("plugins", pluginName, "module");
 			if (!await fs.pathExists(modulePath)) {
 				continue;
 			}
 
-			let moduleJsonPath = path.join(modulePath, 'module.json');
+			let moduleJsonPath = path.join(modulePath, "module.json");
 			if (!await fs.pathExists(moduleJsonPath)) {
 				throw new Error(`Module for plugin ${pluginName} is missing module.json`);
 			}
@@ -352,25 +351,26 @@ class Instance extends link.Link{
 				throw new Error(`Expected name of module for plugin ${pluginName} to match the plugin name`);
 			}
 
-			module = Object.assign({
+			module = {
 				version: plugin.info.version,
-				dependencies: { 'clusterio': '*' },
+				dependencies: { "clusterio": "*" },
 				path: modulePath,
 				load: [],
 				require: [],
-			}, module);
+				...module,
+			};
 			modules.set(module.name, module);
 		}
 
 		// Find stand alone modules to load
 		// XXX for now it's assumed all available modules should be loaded.
-		for (let entry of await fs.readdir('modules', { withFileTypes: true })) {
+		for (let entry of await fs.readdir("modules", { withFileTypes: true })) {
 			if (entry.isDirectory()) {
 				if (modules.has(entry.name)) {
 					throw new Error(`Module with name ${entry.name} already exists in a plugin`);
 				}
 
-				let moduleJsonPath = path.join('modules', entry.name, 'module.json');
+				let moduleJsonPath = path.join("modules", entry.name, "module.json");
 				if (!await fs.pathExists(moduleJsonPath)) {
 					throw new Error(`Module ${entry.name} is missing module.json`);
 				}
@@ -380,12 +380,13 @@ class Instance extends link.Link{
 					throw new Error(`Expected name of module ${entry.name} to match the directory name`);
 				}
 
-				module = Object.assign({
-					path: path.join('modules', entry.name),
-					dependencies: { 'clusterio': '*' },
+				module = {
+					path: path.join("modules", entry.name),
+					dependencies: { "clusterio": "*" },
 					load: [],
 					require: [],
-				}, module);
+					...module,
+				};
 				modules.set(module.name, module);
 			}
 		}
@@ -402,13 +403,13 @@ class Instance extends link.Link{
 	 * @param {String} saveName - Name of save game to load.
 	 */
 	async start(saveName) {
-		this.server.on('rcon-ready', () => {
+		this.server.on("rcon-ready", () => {
 			console.log("Clusterio | RCON connection established");
 		});
 
 		this.server.on("exit", () => this.notifyExit());
 		await this.server.start(saveName);
-		await this.server.disableAchievements()
+		await this.server.disableAchievements();
 		await this.updateInstanceData();
 
 		await plugin.invokeHook(this.plugins, "onStart");
@@ -459,12 +460,12 @@ class Instance extends link.Link{
 	}
 
 	async getMetricsRequestHandler() {
-		let results = []
+		let results = [];
 		if (this._running) {
 			let pluginResults = await plugin.invokeHook(this.plugins, "onMetrics");
 			for (let metricIterator of pluginResults) {
 				for await (let metric of metricIterator) {
-					results.push(prometheus.serializeResult(metric))
+					results.push(prometheus.serializeResult(metric));
 				}
 			}
 		}
@@ -482,7 +483,7 @@ class Instance extends link.Link{
 	async startInstanceRequestHandler(message) {
 		let saveName = message.data.save;
 		try {
-			saveName = await this.prepare(saveName)
+			saveName = await this.prepare(saveName);
 		} catch (err) {
 			this.notifyExit();
 			throw err;
@@ -536,7 +537,7 @@ class Instance extends link.Link{
 				},
 			});
 			if (response.statusCode !== 200) {
-				throw Error(`Upload failed: ${response.statusCode} ${response.statusMessage}: ${response.body}`)
+				throw Error(`Upload failed: ${response.statusCode} ${response.statusMessage}: ${response.body}`);
 			}
 
 		} finally {
@@ -569,6 +570,8 @@ class Instance extends link.Link{
 	 * the directory of the instance.  For example instance.path("mods")
 	 * returns a path to the mods directory of the instance.  If no parts are
 	 * given it returns a path to the directory of the instance.
+	 *
+	 * @returns {string} path in instance directory.
 	 */
 	path(...parts) {
 		return path.join(this._dir, ...parts);
@@ -585,7 +588,7 @@ class Instance extends link.Link{
  * @param {Map<integer, Object>} instanceInfos -
  *     mapping between instance id and information about this instance.
  * @param {string} instancesDir - Directory containing instances
- * @param logger - console like logging interface.
+ * @param {Object} logger - console like logging interface.
  */
 async function discoverInstances(instanceInfos, instancesDir, logger) {
 	for (let entry of await fs.readdir(instancesDir, { withFileTypes: true })) {
@@ -622,7 +625,7 @@ async function discoverInstances(instanceInfos, instancesDir, logger) {
 
 class InstanceConnection extends link.Link {
 	constructor(connector, slave, instanceId) {
-		super('slave', 'instance', connector);
+		super("slave", "instance", connector);
 		this.slave = slave;
 		this.instanceId = instanceId;
 		this.plugins = new Map();
@@ -717,7 +720,7 @@ class Slave extends link.Link {
 	// I don't like God classes, but the alternative of putting all this state
 	// into global variables is not much better.
 	constructor(connector, slaveConfig, pluginInfos) {
-		super('slave', 'master', connector);
+		super("slave", "master", connector);
 		link.attachAllMessages(this);
 
 		this.pluginInfos = pluginInfos;
@@ -750,9 +753,9 @@ class Slave extends link.Link {
 					setBlocking(true);
 					console.error("ERROR: Unexpected error during shutdown");
 					console.error(err);
-					process.exit(1)
+					process.exit(1);
 				});
-			});;
+			});
 		});
 
 		this.connector.on("close", () => {
@@ -769,7 +772,7 @@ class Slave extends link.Link {
 						setBlocking(true);
 						console.error("ERROR: Unexpected error during shutdown");
 						console.error(err);
-						process.exit(1)
+						process.exit(1);
 					});
 				});
 
@@ -779,7 +782,7 @@ class Slave extends link.Link {
 					setBlocking(true);
 					console.error("ERROR: Unexpected error during shutdown");
 					console.error(err);
-					process.exit(1)
+					process.exit(1);
 				});
 			}
 		});
@@ -795,7 +798,7 @@ class Slave extends link.Link {
 
 	async _findNewInstanceDir(name) {
 		try {
-			checkFilename(name)
+			checkFilename(name);
 		} catch (err) {
 			throw new Error(`Instance name ${err.message}`);
 		}
@@ -803,7 +806,7 @@ class Slave extends link.Link {
 		// For now add dashes until an unused directory name is found
 		let dir = path.join(this.config.get("slave.instances_directory"), name);
 		while (await fs.pathExists(dir)) {
-			dir += '-';
+			dir += "-";
 		}
 
 		return dir;
@@ -821,7 +824,7 @@ class Slave extends link.Link {
 		}
 
 		if (request.plugin && !instanceConnection.plugins.has(request.plugin)) {
-			throw new errors.RequestError(`Instance ID ${instanceId} does not have ${request.plugin} plugin loaded`)
+			throw new errors.RequestError(`Instance ID ${instanceId} does not have ${request.plugin} plugin loaded`);
 		}
 
 		return await request.send(instanceConnection, message.data);
@@ -861,7 +864,7 @@ class Slave extends link.Link {
 			// XXX: race condition on multiple simultanious calls
 			let instanceDir = await this._findNewInstanceDir(instanceConfig.get("instance.name"));
 
-			await Instance.create(instanceConfig, instanceDir, this.config.get("slave.factorio_directory"));
+			await Instance.create(instanceDir, this.config.get("slave.factorio_directory"));
 			instanceInfo = {
 				path: instanceDir,
 				config: instanceConfig,
@@ -872,10 +875,10 @@ class Slave extends link.Link {
 
 
 		// save a copy of the instance config
-		let warnedOutput = Object.assign(
-			{ _warning: "Changes to this file will be overwritten by the master server's copy." },
-			instanceInfo.config.serialize()
-		);
+		let warnedOutput = {
+			_warning: "Changes to this file will be overwritten by the master server's copy.",
+			...instanceInfo.config.serialize(),
+		};
 		await fs.outputFile(
 			path.join(instanceInfo.path, "instance.json"),
 			JSON.stringify(warnedOutput, null, 4)
@@ -884,6 +887,9 @@ class Slave extends link.Link {
 
 	/**
 	 * Initialize and connect an unloaded instance
+	 *
+	 * @param {number} instanceId - ID of instance to initialize.
+	 * @returns {module:slave~InstanceConnection} connection to instance.
 	 */
 	async _connectInstance(instanceId) {
 		let instanceInfo = this.instanceInfos.get(instanceId);
@@ -919,10 +925,10 @@ class Slave extends link.Link {
 		}
 
 		for await (let result of prometheus.defaultRegistry.collect()) {
-			if (result.metric.name.startsWith('process_')) {
+			if (result.metric.name.startsWith("process_")) {
 				results.push(prometheus.serializeResult(result, {
-					addLabels: { 'slave_id': String(this.config.get("slave.id")) },
-					metricName: result.metric.name.replace('process_', 'clusterio_slave_'),
+					addLabels: { "slave_id": String(this.config.get("slave.id")) },
+					metricName: result.metric.name.replace("process_", "clusterio_slave_"),
 				}));
 
 			} else {
@@ -1034,10 +1040,10 @@ function checkFilename(name) {
 	const oneToNine = [1, 2, 3, 4, 5, 6, 7, 8, 9];
 	const badNames = [
 		// Relative path components
-		'.', '..',
+		".", "..",
 
 		// Reserved filenames in Windows
-		'CON', 'PRN', 'AUX', 'NUL',
+		"CON", "PRN", "AUX", "NUL",
 		...oneToNine.map(n => `COM${n}`),
 		...oneToNine.map(n => `LPT${n}`),
 	];
@@ -1099,7 +1105,7 @@ async function symlinkMods(instance, sharedMods, logger) {
 	let instanceModsEntries = new Set(await fs.readdir(instance.path("mods")));
 	for (let entry of await fs.readdir(sharedMods, { withFileTypes: true })) {
 		if (entry.isFile()) {
-			if (['.zip', '.dat'].includes(path.extname(entry.name))) {
+			if ([".zip", ".dat"].includes(path.extname(entry.name))) {
 				if (!instanceModsEntries.has(entry.name)) {
 					logger.log(`linking ${entry.name} from ${sharedMods}`);
 					let target = path.join(sharedMods, entry.name);
@@ -1130,17 +1136,17 @@ async function symlinkMods(instance, sharedMods, logger) {
 
 async function startSlave() {
 	// add better stack traces on promise rejection
-	process.on('unhandledRejection', r => console.log(r));
+	process.on("unhandledRejection", r => console.log(r));
 
 	// argument parsing
 	const args = yargs
 		.scriptName("slave")
 		.usage("$0 <command> [options]")
-		.option('config', {
+		.option("config", {
 			nargs: 1,
 			describe: "slave config file to use",
-			default: 'config-slave.json',
-			type: 'string',
+			default: "config-slave.json",
+			type: "string",
 		})
 		.command("config", "Manage Slave config", config.configCommand)
 		.command("run", "Run slave")
@@ -1160,7 +1166,7 @@ async function startSlave() {
 		await slaveConfig.load(JSON.parse(await fs.readFile(args.config)));
 
 	} catch (err) {
-		if (err.code === 'ENOENT') {
+		if (err.code === "ENOENT") {
 			console.log("Config not found, initializing new config");
 			await slaveConfig.init();
 
@@ -1210,8 +1216,8 @@ async function startSlave() {
 	let slave = new Slave(slaveConnector, slaveConfig, pluginInfos);
 
 	// Handle interrupts
-	let secondSigint = false
-	process.on('SIGINT', () => {
+	let secondSigint = false;
+	process.on("SIGINT", () => {
 		if (secondSigint) {
 			console.log("Caught second interrupt, terminating immediately");
 			process.exit(1);
@@ -1232,37 +1238,6 @@ async function startSlave() {
 	});
 
 	await slaveConnector.connect();
-
-	/*
-	} else if (command == "manage"){
-		await manage(config, instance);
-		// process.exit(0);
-	*/
-}
-
-// string, function
-// returns [{modName:string,hash:string}, ... ]
-function hashMods(instance, callback) {
-	if(!callback) {
-		throw new Error("ERROR in function hashMods NO CALLBACK");
-	}
-
-	function hashMod(name) {
-		if (path.extname(name) != ".zip") {
-			// Can't hash unzipped mods, return null that's filtered out later
-			return null;
-		} else {
-			return hashFile(instance.path("mods", name)).then(hash => (
-				{modName: name, hash: hash}
-			));
-		}
-	}
-
-	let promises = fs.readdirSync(instance.path("mods")).map(hashMod);
-	Promise.all(promises).then(hashes => {
-		// Remove null entries from hashMod
-		callback(hashes.filter(entry => entry !== null));
-	});
 }
 
 module.exports = {
diff --git a/test/clusterctl.js b/test/clusterctl.js
index 8dd1c36e..acb6c5b0 100644
--- a/test/clusterctl.js
+++ b/test/clusterctl.js
@@ -1,10 +1,11 @@
-const assert = require('assert').strict;
-const chalk = require('chalk');
+"use strict";
+const assert = require("assert").strict;
+const chalk = require("chalk");
 
-const errors = require('lib/errors');
-const { testLines } = require('./lib/factorio/lines');
-const clusterctl = require('../clusterctl.js');
-const mock = require('./mock');
+const errors = require("lib/errors");
+const { testLines } = require("./lib/factorio/lines");
+const clusterctl = require("../clusterctl.js");
+const mock = require("./mock");
 
 
 describe("clusterctl", function() {
@@ -24,13 +25,13 @@ describe("clusterctl", function() {
 	});
 
 	let mockConnector = new mock.MockConnector();
-	mockConnector.on('send', function(message) {
-		if (message.type === 'list_instances_request') {
-			this.emit('message', {
-				seq: 1, type: 'list_instances_response',
+	mockConnector.on("send", function(message) {
+		if (message.type === "list_instances_request") {
+			this.emit("message", {
+				seq: 1, type: "list_instances_response",
 				data: {
 					seq: message.seq,
-					list: [{ id: 57, assigned_slave: 4, name: 'Test Instance' }],
+					list: [{ id: 57, assigned_slave: 4, name: "Test Instance" }],
 				},
 			});
 		}
diff --git a/test/integration/clusterio.js b/test/integration/clusterio.js
index 18fe1b80..73b5ee4e 100644
--- a/test/integration/clusterio.js
+++ b/test/integration/clusterio.js
@@ -1,8 +1,9 @@
+"use strict";
 const assert = require("assert").strict;
 const fs = require("fs-extra");
 const path = require("path");
-const validateHTML = require('html5-validator');
-const parallel = require('mocha.parallel');
+const validateHTML = require("html5-validator");
+const parallel = require("mocha.parallel");
 
 const link = require("lib/link");
 
@@ -113,7 +114,7 @@ describe("Integration of Clusterio", function() {
 					],
 					[
 						"ignore_player_limit_for_returning_players", true,
-						"ignore-player-limit-for-returning-players", "Ignore player limit for returning players: true."
+						"ignore-player-limit-for-returning-players", "Ignore player limit for returning players: true.",
 					],
 					[
 						"max_players", 11,
@@ -155,7 +156,7 @@ describe("Integration of Clusterio", function() {
 					],
 				];
 
-				for (let [prop, value, , ] of testConfigs) {
+				for (let [prop, value, ,] of testConfigs) {
 					value = `"'${JSON.stringify(value).replace(/"/g, process.platform === "win32" ? '""' : '\\"')}'"`;
 					let args = `--instance test --field factorio.settings --prop ${prop} --value ${value}`;
 					await exec(`node clusterctl --config ${controlConfigPath} set-instance-config-prop ${args}`);
@@ -202,7 +203,7 @@ describe("Integration of Clusterio", function() {
 				await exec(`node clusterctl --config ${controlConfigPath} create-role --name temp --description "A temp role" --permissions core.control.connect`);
 				let result = await link.messages.listRoles.send(getControl());
 				let role = result.list.find(role => role.name === "temp");
-				assert.deepEqual(role, { id: 5, name: "temp", description: "A temp role", permissions: ["core.control.connect"]});
+				assert.deepEqual(role, { id: 5, name: "temp", description: "A temp role", permissions: ["core.control.connect"] });
 			});
 		});
 
@@ -211,7 +212,7 @@ describe("Integration of Clusterio", function() {
 				await exec(`node clusterctl --config ${controlConfigPath} edit-role --role temp --name new --description "A new role" --permissions`);
 				let result = await link.messages.listRoles.send(getControl());
 				let role = result.list.find(role => role.name === "new");
-				assert.deepEqual(role, { id: 5, name: "new", description: "A new role", permissions: []});
+				assert.deepEqual(role, { id: 5, name: "new", description: "A new role", permissions: [] });
 			});
 		});
 
diff --git a/test/integration/export.js b/test/integration/export.js
index 4fc72d8f..6c6fc233 100644
--- a/test/integration/export.js
+++ b/test/integration/export.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const path = require("path");
 
diff --git a/test/integration/index.js b/test/integration/index.js
index e8fe86ce..c7305c0a 100644
--- a/test/integration/index.js
+++ b/test/integration/index.js
@@ -1,3 +1,4 @@
+"use strict";
 const path = require("path");
 const fs = require("fs-extra");
 const child_process = require("child_process");
@@ -22,6 +23,7 @@ class TestControl extends link.Link {
 	}
 
 	async debugWsMessageEventHandler() { }
+
 	async instanceOutputEventHandler() { }
 }
 
@@ -34,6 +36,7 @@ class TestControlConnector extends link.WebSocketClientConnector {
 // Mark that this test takes a lot of time, or depeneds on a test
 // that takes a lot of time.
 function slowTest(test) {
+	// eslint-disable-next-line no-process-env
 	if (process.env.FAST_TEST) {
 		test.skip();
 	}
@@ -67,7 +70,7 @@ async function exec(...args) {
 }
 
 async function sendRcon(instanceId, command) {
-	let response = await link.messages.sendRcon.send(control, { instance_id: instanceId, command })
+	let response = await link.messages.sendRcon.send(control, { instance_id: instanceId, command });
 	return response.result;
 }
 
@@ -86,8 +89,8 @@ function spawn(name, cmd, waitFor) {
 				resolve(process);
 			}
 			console.log(name, line);
-		})
-		let stderr = new server._LineSplitter((line) => { console.log(name, line.toString("utf8")); })
+		});
+		let stderr = new server._LineSplitter((line) => { console.log(name, line.toString("utf8")); });
 		process.stdout.on("data", chunk => { stdout.data(chunk); });
 		process.stdout.on("close", () => { stdout.end(); });
 		process.stderr.on("data", chunk => { stderr.data(chunk); });
diff --git a/test/integration/link.js b/test/integration/link.js
index ed3e5196..dec7133f 100644
--- a/test/integration/link.js
+++ b/test/integration/link.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const events = require("events");
 const jwt = require("jsonwebtoken");
diff --git a/test/integration/patch.js b/test/integration/patch.js
index 1101e147..1baf6b1b 100644
--- a/test/integration/patch.js
+++ b/test/integration/patch.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const fs = require("fs-extra");
 const jszip = require("jszip");
@@ -9,7 +10,7 @@ const { slowTest } = require("./index");
 
 
 // The server integration test is required to run before this one
-require("./server")
+require("./server");
 
 describe("Integration of lib/factorio/patch", function() {
 	describe("patch()", function() {
diff --git a/test/integration/server.js b/test/integration/server.js
index dad51b53..810570c1 100644
--- a/test/integration/server.js
+++ b/test/integration/server.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const events = require("events");
 const fs = require("fs-extra");
@@ -26,13 +27,13 @@ describe("Integration of lib/factorio/server", function() {
 
 		before(async function() {
 			// Delete result from previous run of these tests
-			if (fs.existsSync(writePath)) {
+			if (await fs.pathExists(writePath)) {
 				await fs.remove(writePath);
 			}
 
 			await fs.ensureDir(writePath);
 			logFile = fs.createWriteStream(path.join(writePath, "log.txt"), "utf8");
-			server.on('output', function(output) {
+			server.on("output", function(output) {
 				logFile.write(JSON.stringify(output) + "\n");
 			});
 
@@ -119,7 +120,7 @@ describe("Integration of lib/factorio/server", function() {
 				log(".sendRcon()");
 
 				let result = await server.sendRcon("/sc rcon.print('success')");
-				assert.equal(result, 'success\n');
+				assert.equal(result, "success\n");
 			});
 			it("throws on non-empty response when enabled", async function() {
 				slowTest(this);
@@ -149,20 +150,20 @@ describe("Integration of lib/factorio/server", function() {
 				slowTest(this);
 				log(".startScenario()");
 
-				let pass = false
+				let pass = false;
 				function filter(output) {
 					if (output.message === "test_scenario init") {
 						pass = true;
 					}
 				}
-				server.on('output', filter);
+				server.on("output", filter);
 
 				await server.startScenario("test_scenario");
 
 				log(".stop()");
 				await server.stop();
 
-				server.off('output', filter);
+				server.off("output", filter);
 				assert(pass, "server did not output line from test scenario");
 			});
 		});
@@ -191,7 +192,7 @@ describe("Integration of lib/factorio/server", function() {
 
 				await server.start("test.zip");
 				if (!server._rconReady) {
-					await events.once(server, 'rcon-ready');
+					await events.once(server, "rcon-ready");
 				}
 				server.sendRcon("/c while true do end").catch(() => {});
 				await new Promise((resolve) => setTimeout(resolve, 300));
@@ -210,7 +211,7 @@ describe("Integration of lib/factorio/server", function() {
 				log(".start() for kill detection");
 
 				let startPromise = server.start("test.zip");
-				server.once('output', () => server._server.kill('SIGKILL'));
+				server.once("output", () => server._server.kill("SIGKILL"));
 
 				await assert.rejects(
 					startPromise,
diff --git a/test/lib/config/classes.js b/test/lib/config/classes.js
index e094e4a2..802a8860 100644
--- a/test/lib/config/classes.js
+++ b/test/lib/config/classes.js
@@ -25,35 +25,35 @@ describe("lib/config/classes", function() {
 				for (let [def, error] of [
 					[
 						{ name: "a", type: "invalid", optional: true },
-						"invalid is not a valid type"
+						"invalid is not a valid type",
 					],
 					[
 						{ name: [], type: "string", optional: true },
-						"name must be a string"
+						"name must be a string",
 					],
 					[
 						{ name: "a", type: "string", enum: true, optional: true },
-						"enum must be an array"
+						"enum must be an array",
 					],
 					[
 						{ name: "a", title: 2, type: "string", optional: true },
-						"title must be a string"
+						"title must be a string",
 					],
 					[
 						{ name: "a", description: 2, type: "string", optional: true },
-						"description must be a string"
+						"description must be a string",
 					],
 					[
 						{ name: "a", type: "string", optional: "yes" },
-						"optional must be a boolean"
+						"optional must be a boolean",
 					],
 					[
 						{ name: "a", type: "string", initial_value: 1 },
-						"initial_value must match the type or be a function"
+						"initial_value must match the type or be a function",
 					],
 					[
 						{ name: "a", type: "string" },
-						"Non-optional field a needs an initial_value"
+						"Non-optional field a needs an initial_value",
 					],
 				]) {
 					assert.throws(() => TestGroup.define(def), new Error(error));
@@ -97,13 +97,13 @@ describe("lib/config/classes", function() {
 					enum: ["a", "b", "c"],
 					optional: true,
 					initial_value: "b",
-				}
+				};
 				TestGroup.define(field);
 				// Generated properties
 				field.fullName = "test_group.enum";
 
 				assert.deepEqual(TestGroup._definitions.get("enum"), field);
-			})
+			});
 		});
 
 		describe("get definitions", function() {
@@ -191,7 +191,7 @@ describe("lib/config/classes", function() {
 					func: 22,
 					bool: null,
 					json: { valid: true },
-				}})
+				}});
 
 				assert.equal(testInstance.get("enum"), "c");
 				assert.equal(testInstance.get("test"), "blah");
@@ -218,7 +218,7 @@ describe("lib/config/classes", function() {
 					alpha: null,
 					beta: "decay",
 					gamma: 99,
-				}
+				};
 
 				let testInstance = new TestGroup();
 				await testInstance.load(null, { name: "test_group", fields: testFields });
@@ -253,11 +253,11 @@ describe("lib/config/classes", function() {
 					new Error("Expected fields to be an object, not undefined")
 				);
 				assert.throws(
-					() => testInstance.update({ name: "test_group", fields: []}, false),
+					() => testInstance.update({ name: "test_group", fields: [] }, false),
 					new Error("Expected fields to be an object, not array")
 				);
 				assert.throws(
-					() => testInstance.update({ name: "test_group", fields: null}, false),
+					() => testInstance.update({ name: "test_group", fields: null }, false),
 					new Error("Expected fields to be an object, not null")
 				);
 			});
@@ -277,43 +277,43 @@ describe("lib/config/classes", function() {
 					() => testInstance.set("bar", 1),
 					new classes.InvalidField("No field named 'bar'")
 				);
-			})
+			});
 
 			it("should throw if field is not in enum", function() {
 				assert.throws(
 					() => testInstance.set("enum", "bar"),
 					new Error("Expected one of [a, b, c], not bar")
 				);
-			})
+			});
 
 			it("should work if field is in enum", function() {
-				testInstance.set("enum", "c"),
+				testInstance.set("enum", "c");
 				assert.equal(testInstance.get("enum"), "c");
-			})
+			});
 
 			it("should throw if field is not optional", function() {
 				assert.throws(
 					() => testInstance.set("func", null),
 					new Error("Field func cannot be null")
 				);
-			})
+			});
 
 			it("should work if field is optional", function() {
-				testInstance.set("test", "spam"),
+				testInstance.set("test", "spam");
 				assert.equal(testInstance.get("test"), "spam");
-			})
+			});
 
 			it("should throw if field is of wrong type", function() {
 				assert.throws(
 					() => testInstance.set("test", 1),
 					new Error("Expected type of test to be string, not number")
 				);
-			})
+			});
 
 			it("should treat empty string as null", function() {
-				testInstance.set("test", ""),
+				testInstance.set("test", "");
 				assert.equal(testInstance.get("test"), null);
-			})
+			});
 
 			it("should auto convert string to boolean if possible", function() {
 				testInstance.set("bool", "true");
@@ -374,14 +374,14 @@ describe("lib/config/classes", function() {
 					() => testInstance.setProp("bar", 1),
 					new classes.InvalidField("No field named 'bar'")
 				);
-			})
+			});
 
 			it("should throw if field is not an object", function() {
 				assert.throws(
 					() => testInstance.setProp("enum", "a"),
 					new classes.InvalidField("Cannot set property on non-object field 'enum'")
 				);
-			})
+			});
 
 			it("should work if field is an object", function() {
 				testInstance.set("json", { prev: 32, test: false });
@@ -451,7 +451,8 @@ describe("lib/config/classes", function() {
 			});
 			it("should construct a finalized class", function() {
 				TestConfig.finalize();
-				new TestConfig();
+				let config = new TestConfig();
+				assert(config);
 			});
 		});
 
@@ -461,7 +462,7 @@ describe("lib/config/classes", function() {
 				await testInstance.init();
 				assert.equal(testInstance.get("alpha.foo"), null);
 				assert.deepEqual(testInstance.get("beta.bar"), {});
-			})
+			});
 		});
 
 		describe(".serialize()", function() {
@@ -477,10 +478,10 @@ describe("lib/config/classes", function() {
 						{
 							name: "beta",
 							fields: { bar: {} },
-						}
-					]
+						},
+					],
 				});
-			})
+			});
 		});
 
 		describe(".load()", function() {
@@ -521,8 +522,8 @@ describe("lib/config/classes", function() {
 					{
 						name: "beta",
 						fields: { bar: { value: 20 }},
-					}
-				]
+					},
+				];
 
 				let testInstance = new TestConfig();
 				await testInstance.load({ groups: testGroups });
@@ -543,7 +544,7 @@ describe("lib/config/classes", function() {
 					{
 						name: "beta",
 						fields: { bar: { value: 30 }},
-					}
+					},
 				]}, false);
 
 				assert.deepEqual(testInstance.serialize(), {
@@ -559,10 +560,10 @@ describe("lib/config/classes", function() {
 						{
 							name: "beta",
 							fields: { bar: { value: 30 }},
-						}
+						},
 					],
 				});
-			})
+			});
 		});
 
 		describe(".group()", function() {
@@ -580,14 +581,14 @@ describe("lib/config/classes", function() {
 				let testInstance = new TestConfig();
 				await testInstance.init();
 
-				assert.throws(() => testInstance.get("invalid"), new Error("No config group named 'invalid'"))
+				assert.throws(() => testInstance.get("invalid"), new Error("No config group named 'invalid'"));
 			});
 
 			it("should throw if no field is specified", async function() {
 				let testInstance = new TestConfig();
 				await testInstance.init();
 
-				assert.throws(() => testInstance.get("alpha"), new Error("No field named ''"))
+				assert.throws(() => testInstance.get("alpha"), new Error("No field named ''"));
 			});
 		});
 
diff --git a/test/lib/database.js b/test/lib/database.js
index f2f31fc9..2b4670bc 100644
--- a/test/lib/database.js
+++ b/test/lib/database.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const fs = require("fs-extra");
 const path = require("path");
@@ -12,21 +13,21 @@ describe("lib/database", function() {
 				new Error("Expected all keys to be string but got number")
 			);
 			assert.throws(
-				() => database.mapToObject(new Map([[Symbol(), 1]])),
+				() => database.mapToObject(new Map([[Symbol("test"), 1]])),
 				new Error("Expected all keys to be string but got symbol")
 			);
 		});
 
 		it("should throw convert a map to an object", function() {
 			assert.deepEqual(
-				database.mapToObject(new Map([['a', 1], ['b', true]])),
-				{'a': 1, 'b': true}
+				database.mapToObject(new Map([["a", 1], ["b", true]])),
+				{ "a": 1, "b": true }
 			);
 		});
 	});
 
 	describe("loadJsonAsMap()", function() {
-		let badTypes = ['null', 'array', 'number', 'string', 'boolean'];
+		let badTypes = ["null", "array", "number", "string", "boolean"];
 
 		for (let type of badTypes) {
 			it(`should reject on ${type} JSON`, async function() {
@@ -47,7 +48,7 @@ describe("lib/database", function() {
 		it("should work on object JSON", async function() {
 			assert.deepEqual(
 				await database.loadJsonAsMap(path.join("test", "file", "json", "load_map.json")),
-				new Map([['a', 1], ['b', true]])
+				new Map([["a", 1], ["b", true]])
 			);
 		});
 
@@ -67,7 +68,7 @@ describe("lib/database", function() {
 					await fs.unlink(testFile);
 				} catch (err) {
 					/* istanbul ignore if */
-					if (err.code !== 'ENOENT') {
+					if (err.code !== "ENOENT") {
 						throw err;
 					}
 				}
@@ -75,18 +76,18 @@ describe("lib/database", function() {
 
 			await deleteTestFile();
 			await database.saveMapAsJson(
-				testFile, new Map([['c', {}], ['d', "foo"]])
+				testFile, new Map([["c", {}], ["d", "foo"]])
 			);
 
 			assert.equal(
-				await fs.readFile(testFile, {encoding: 'utf-8'}),
+				await fs.readFile(testFile, { encoding: "utf-8" }),
 				'{\n    "c": {},\n    "d": "foo"\n}'
 			);
 		});
 	});
 
 	describe("loadJsonArrayAsMap()", function() {
-		let badTypes = ['null', 'object', 'number', 'string', 'boolean'];
+		let badTypes = ["null", "object", "number", "string", "boolean"];
 
 		for (let type of badTypes) {
 			it(`should reject on ${type} JSON`, async function() {
@@ -121,7 +122,7 @@ describe("lib/database", function() {
 		it("should work on array JSON", async function() {
 			assert.deepEqual(
 				await database.loadJsonArrayAsMap(path.join("test", "file", "json", "load_array_map.json")),
-				new Map([['a', {id: 'a'}], ['b', {id: 'b'}]])
+				new Map([["a", { id: "a" }], ["b", { id: "b" }]])
 			);
 		});
 
@@ -141,7 +142,7 @@ describe("lib/database", function() {
 					await fs.unlink(testFile);
 				} catch (err) {
 					/* istanbul ignore if */
-					if (err.code !== 'ENOENT') {
+					if (err.code !== "ENOENT") {
 						throw err;
 					}
 				}
@@ -149,11 +150,11 @@ describe("lib/database", function() {
 
 			await deleteTestFile();
 			await database.saveMapAsJsonArray(
-				testFile, new Map([['c', {id: 'c'}], ['d', {id: 'd'}]])
+				testFile, new Map([["c", { id: "c" }], ["d", { id: "d" }]])
 			);
 
 			assert.equal(
-				await fs.readFile(testFile, {encoding: 'utf-8'}),
+				await fs.readFile(testFile, { encoding: "utf-8" }),
 				'[\n    {\n        "id": "c"\n    },\n    {\n        "id": "d"\n    }\n]'
 			);
 		});
@@ -167,18 +168,18 @@ describe("lib/database", function() {
 			});
 
 			it("should restore the passed serialized database", function() {
-				let items = new database.ItemDatabase({'a': 1, 'b': 2});
-				assert.deepEqual(items._items, new Map([['a', 1], ['b', 2]]));
+				let items = new database.ItemDatabase({ "a": 1, "b": 2 });
+				assert.deepEqual(items._items, new Map([["a", 1], ["b", 2]]));
 			});
 
 			it("should throw on invalid serialized database", function() {
 				assert.throws(
-					() => new database.ItemDatabase({'a': NaN}),
+					() => new database.ItemDatabase({ "a": NaN }),
 					new Error("count must be a number")
 				);
 
 				assert.throws(
-					() => new database.ItemDatabase({'a': 'a'}),
+					() => new database.ItemDatabase({ "a": "a" }),
 					new Error("count must be a number")
 				);
 			});
@@ -186,32 +187,32 @@ describe("lib/database", function() {
 
 		describe(".serialize()", function() {
 			it("should return a serialized database", function() {
-				let items = new database.ItemDatabase({'a': 10});
-				assert.deepEqual(items.serialize(), {'a': 10});
+				let items = new database.ItemDatabase({ "a": 10 });
+				assert.deepEqual(items.serialize(), { "a": 10 });
 			});
 
 			it("should remove zero count entries", function() {
-				let items = new database.ItemDatabase({'a': 0});
+				let items = new database.ItemDatabase({ "a": 0 });
 				assert.deepEqual(items.serialize(), {});
 			});
 		});
 
 		describe(".size", function() {
 			it("should give an approximate size of the database", function() {
-				let items = new database.ItemDatabase({'a': 10});
+				let items = new database.ItemDatabase({ "a": 10 });
 				assert.equal(items.size, 1);
 			});
 		});
 
 		describe(".getItemCount()", function() {
 			it("should return the count of the given item", function() {
-				let items = new database.ItemDatabase({'a': 10});
-				assert.equal(items.getItemCount('a'), 10);
+				let items = new database.ItemDatabase({ "a": 10 });
+				assert.equal(items.getItemCount("a"), 10);
 			});
 
 			it("should return zero if item does not exist", function() {
 				let items = new database.ItemDatabase();
-				assert.equal(items.getItemCount('b'), 0);
+				assert.equal(items.getItemCount("b"), 0);
 			});
 
 			it("should throw on invalid name", function() {
@@ -226,15 +227,15 @@ describe("lib/database", function() {
 		describe(".addItem()", function() {
 			it("should add a new item", function() {
 				let items = new database.ItemDatabase();
-				items.addItem('a', 10);
-				assert.deepEqual(items._items, new Map([['a', 10]]));
-			})
+				items.addItem("a", 10);
+				assert.deepEqual(items._items, new Map([["a", 10]]));
+			});
 
 			it("should add an existing item", function() {
-				let items = new database.ItemDatabase({'a': 10});
-				items.addItem('a', 10);
-				assert.deepEqual(items._items, new Map([['a', 20]]));
-			})
+				let items = new database.ItemDatabase({ "a": 10 });
+				items.addItem("a", 10);
+				assert.deepEqual(items._items, new Map([["a", 20]]));
+			});
 
 			it("should throw on invalid name", function() {
 				let items = new database.ItemDatabase();
@@ -247,11 +248,11 @@ describe("lib/database", function() {
 			it("should throw on invalid count", function() {
 				let items = new database.ItemDatabase();
 				assert.throws(
-					() => items.addItem('a', NaN),
+					() => items.addItem("a", NaN),
 					new Error("count must be a number")
 				);
 				assert.throws(
-					() => items.addItem('a', "1"),
+					() => items.addItem("a", "1"),
 					new Error("count must be a number")
 				);
 			});
@@ -259,16 +260,16 @@ describe("lib/database", function() {
 
 		describe(".removeItem()", function() {
 			it("should remove an existing item", function() {
-				let items = new database.ItemDatabase({'a': 20});
-				items.removeItem('a', 10);
-				assert.deepEqual(items._items, new Map([['a', 10]]));
-			})
+				let items = new database.ItemDatabase({ "a": 20 });
+				items.removeItem("a", 10);
+				assert.deepEqual(items._items, new Map([["a", 10]]));
+			});
 
 			it("should turn a non-existing item negative", function() {
 				let items = new database.ItemDatabase();
-				items.removeItem('a', 10);
-				assert.deepEqual(items._items, new Map([['a', -10]]));
-			})
+				items.removeItem("a", 10);
+				assert.deepEqual(items._items, new Map([["a", -10]]));
+			});
 
 			it("should throw on invalid name", function() {
 				let items = new database.ItemDatabase();
@@ -281,11 +282,11 @@ describe("lib/database", function() {
 			it("should throw on invalid count", function() {
 				let items = new database.ItemDatabase();
 				assert.throws(
-					() => items.removeItem('a', 'b'),
+					() => items.removeItem("a", "b"),
 					new Error("count must be a number")
 				);
 				assert.throws(
-					() => items.removeItem('a', "1"),
+					() => items.removeItem("a", "1"),
 					new Error("count must be a number")
 				);
 			});
diff --git a/test/lib/factorio/export.js b/test/lib/factorio/export.js
index 1c3179b4..d4ce5691 100644
--- a/test/lib/factorio/export.js
+++ b/test/lib/factorio/export.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const path = require("path");
 
@@ -17,5 +18,5 @@ describe("lib/factorio/export", function() {
 			let locale = await factorio._exportLocale(testServer, new Map(), ["base"], "en");
 			assert.deepEqual(locale, new Map([["test.key-a", "1"], ["test.key-b", "2"]]));
 		});
-	});;
+	});
 });
diff --git a/test/lib/factorio/lines.js b/test/lib/factorio/lines.js
index 7d34fdd5..d5ced40e 100644
--- a/test/lib/factorio/lines.js
+++ b/test/lib/factorio/lines.js
@@ -1,113 +1,114 @@
 // Lines for testing the factorio output
 
+"use strict";
 let testLines = new Map([
 	[
 		"   1.306 Info RemoteCommandProcessor.cpp:131: Starting RCON interface at port 4000",
 		{
-			format: 'seconds',
-			time: '1.306',
-			type: 'log',
-			level: 'Info',
+			format: "seconds",
+			time: "1.306",
+			type: "log",
+			level: "Info",
 			file: "RemoteCommandProcessor.cpp:131",
 			message: "Starting RCON interface at port 4000",
-		}
+		},
 	],
 	[
 		"   0.622 Warning FileUtil.cpp:527: test not found; using test.zip",
 		{
-			format: 'seconds',
-			time: '0.622',
-			type: 'log',
-			level: 'Warning',
+			format: "seconds",
+			time: "0.622",
+			type: "log",
+			level: "Warning",
 			file: "FileUtil.cpp:527",
 			message: "test not found; using test.zip",
-		}
+		},
 	],
 	[
 		"   0.554 Error Main.cpp:839: require_user_verification must be enabled for public games.",
 		{
-			format: 'seconds',
-			time: '0.554',
-			type: 'log',
-			level: 'Error',
+			format: "seconds",
+			time: "0.554",
+			type: "log",
+			level: "Error",
 			file: "Main.cpp:839",
 			message: "require_user_verification must be enabled for public games.",
-		}
+		},
 	],
 	[
 		" 640.910 Quitting: remote-quit.",
 		{
-			format: 'seconds',
-			time: '640.910',
-			type: 'generic',
+			format: "seconds",
+			time: "640.910",
+			type: "generic",
 			message: "Quitting: remote-quit.",
-		}
+		},
 	],
 	[
 		"1641.421 Goodbye",
 		{
-			format: 'seconds',
-			time: '1641.421',
-			type: 'generic',
+			format: "seconds",
+			time: "1641.421",
+			type: "generic",
 			message: "Goodbye",
-		}
+		},
 	],
 	[
 		"2019-01-20 10:30:04 [JOIN] User joined the game",
 		{
-			format: 'date',
-			time: '2019-01-20 10:30:04',
-			type: 'action',
+			format: "date",
+			time: "2019-01-20 10:30:04",
+			type: "action",
 			action: "JOIN",
 			message: "User joined the game",
-		}
+		},
 	],
 	[
 		"2019-01-20 10:30:07 [CHAT] User: chat message",
 		{
-			format: 'date',
-			time: '2019-01-20 10:30:07',
-			type: 'action',
+			format: "date",
+			time: "2019-01-20 10:30:07",
+			type: "action",
 			action: "CHAT",
 			message: "User: chat message",
-		}
+		},
 	],
 	[
 		"2019-01-20 10:30:14 [COMMAND] User (command): blah",
 		{
-			format: 'date',
-			time: '2019-01-20 10:30:14',
-			type: 'action',
+			format: "date",
+			time: "2019-01-20 10:30:14",
+			type: "action",
 			action: "COMMAND",
 			message: "User (command): blah",
-		}
+		},
 	],
 	[
 		"2019-01-20 10:30:14 Cannot execute command. Error: [string \"blah\"]:1: syntax error near <eof>",
 		{
-			format: 'date',
-			time: '2019-01-20 10:30:14',
-			type: 'generic',
+			format: "date",
+			time: "2019-01-20 10:30:14",
+			type: "generic",
 			message: "Cannot execute command. Error: [string \"blah\"]:1: syntax error near <eof>",
-		}
+		},
 	],
 	[
 		"2019-01-20 10:30:21 [LEAVE] User left the game",
 		{
-			format: 'date',
-			time: '2019-01-20 10:30:21',
-			type: 'action',
+			format: "date",
+			time: "2019-01-20 10:30:21",
+			type: "action",
 			action: "LEAVE",
 			message: "User left the game",
-		}
+		},
 	],
 	[
 		"Error while running event level::on_nth_tick(1)",
 		{
-			format: 'none',
-			type: 'generic',
+			format: "none",
+			type: "generic",
 			message: "Error while running event level::on_nth_tick(1)",
-		}
+		},
 	],
 	[
 		"4802.763 Info AppManager.cpp:287: Saving to _autosave4 (blocking).",
@@ -118,7 +119,7 @@ let testLines = new Map([
 			level: "Info",
 			file: "AppManager.cpp:287",
 			message: "Saving to _autosave4 (blocking).",
-		}
+		},
 	],
 	[
 		"  10.806 Info AppManager.cpp:394: Saving game as C:\\factorio\\saves\\world.zip",
@@ -129,7 +130,7 @@ let testLines = new Map([
 			level: "Info",
 			file: "AppManager.cpp:394",
 			message: "Saving game as C:\\factorio\\saves\\world.zip",
-		}
+		},
 	],
 	[
 		"4202.780 Info AppManagerStates.cpp:1802: Saving finished",
@@ -140,10 +141,10 @@ let testLines = new Map([
 			level: "Info",
 			file: "AppManagerStates.cpp:1802",
 			message: "Saving finished",
-		}
+		},
 	],
-])
+]);
 
 module.exports = {
 	testLines,
-}
+};
diff --git a/test/lib/factorio/patch.js b/test/lib/factorio/patch.js
index 79eeb422..02a2527b 100644
--- a/test/lib/factorio/patch.js
+++ b/test/lib/factorio/patch.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const fs = require("fs-extra");
 const jszip = require("jszip");
@@ -50,20 +51,20 @@ describe("lib/factorio", function() {
 
 	describe("generateLoader()", function() {
 		let reference = [
-			'-- Auto generated scenario module loader created by Clusterio',
-			'-- Modifications to this file will be lost when loaded in Clusterio',
-			'clusterio_patch_number = 1',
-			'',
+			"-- Auto generated scenario module loader created by Clusterio",
+			"-- Modifications to this file will be lost when loaded in Clusterio",
+			"clusterio_patch_number = 1",
+			"",
 			'local event_handler = require("event_handler")',
-			'',
-			'-- Scenario modules',
+			"",
+			"-- Scenario modules",
 			'event_handler.add_lib(require("foo"))',
-			'',
-			'-- Clusterio modules',
+			"",
+			"-- Clusterio modules",
 			'event_handler.add_lib(require("modules/spam/bar"))',
 			'require("modules/spam/spam")',
-			'',
-		].join('\n');
+			"",
+		].join("\n");
 		let patchInfo = {
 			"patch_number": 1,
 			"scenario": { "modules": ["foo"] },
@@ -85,15 +86,15 @@ describe("lib/factorio", function() {
 	describe("reorderDependencies()", function() {
 		it("should reorder to satisfy simple dependency", function() {
 			let modules = [
-				{ name: 'a', version: '1.0.0', dependencies: {'b': '*'} },
-				{ name: 'b', version: '1.0.0', dependencies: {} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {} },
 			];
 			factorio._reorderDependencies(modules);
-			assert(modules[0].name === 'b', "Dependency was not reorederd");
+			assert(modules[0].name === "b", "Dependency was not reorederd");
 		});
 		it("should throw on invalid version", function() {
 			let modules = [
-				{ name: 'a', version: 'foo', dependencies: {} },
+				{ name: "a", version: "foo", dependencies: {} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
@@ -102,7 +103,7 @@ describe("lib/factorio", function() {
 		});
 		it("should throw on invalid version range", function() {
 			let modules = [
-				{ name: 'a', version: '1.0.0', dependencies: {'b': 'invalid'} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "invalid"} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
@@ -111,16 +112,16 @@ describe("lib/factorio", function() {
 		});
 		it("should throw on missing dependency", function() {
 			let modules = [
-				{ name: 'a', version: '1.0.0', dependencies: {'b': '*'} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
 				new Error("Missing dependency b for module a")
 			);
 			modules = [
-				{ name: 'a', version: '1.0.0', dependencies: {'b': '*'} },
-				{ name: 'b', version: '1.0.0', dependencies: {'c': '*'} },
-				{ name: 'c', version: '1.0.0', dependencies: {'d': '*'} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {"c": "*"} },
+				{ name: "c", version: "1.0.0", dependencies: {"d": "*"} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
@@ -129,8 +130,8 @@ describe("lib/factorio", function() {
 		});
 		it("should throw on outdated dependency", function() {
 			let modules = [
-				{ name: 'a', version: '1.0.0', dependencies: {} },
-				{ name: 'b', version: '1.0.0', dependencies: {'a': '>=2'} },
+				{ name: "a", version: "1.0.0", dependencies: {} },
+				{ name: "b", version: "1.0.0", dependencies: {"a": ">=2"} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
@@ -139,18 +140,18 @@ describe("lib/factorio", function() {
 		});
 		it("should throw on dependency loops", function() {
 			let modules = [
-				{ name: 'a', version: '1.0.0', dependencies: {'b': '*'} },
-				{ name: 'b', version: '1.0.0', dependencies: {'a': '*'} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {"a": "*"} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
 				new Error("Module dependency loop detected: a -> b -> a")
 			);
 			modules = [
-				{ name: 'd', version: '1.0.0', dependencies: {'b': '*'} },
-				{ name: 'a', version: '1.0.0', dependencies: {'b': '*'} },
-				{ name: 'b', version: '1.0.0', dependencies: {'c': '*'} },
-				{ name: 'c', version: '1.0.0', dependencies: {'a': '*'} },
+				{ name: "d", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "a", version: "1.0.0", dependencies: {"b": "*"} },
+				{ name: "b", version: "1.0.0", dependencies: {"c": "*"} },
+				{ name: "c", version: "1.0.0", dependencies: {"a": "*"} },
 			];
 			assert.throws(
 				() => factorio._reorderDependencies(modules),
@@ -170,7 +171,7 @@ describe("lib/factorio", function() {
 				}
 			}
 
-			let names = ['a', 'b', 'c'];
+			let names = ["a", "b", "c"];
 			let successCount = 0;
 			const bitCount = names.length * (names.length - 1);
 			for (let i=0; i < 2**bitCount; i++) {
@@ -186,10 +187,10 @@ describe("lib/factorio", function() {
 					let dependencies = {};
 					for (let k=0; k < names.length - 1; k++) {
 						if (bits[k + j * (names.length - 1)]) {
-							dependencies[names[k + (k >= j)]] = '*';
+							dependencies[names[k + (k >= j)]] = "*";
 						}
 					}
-					modules.push({ name, version: '1.0.0', dependencies });
+					modules.push({ name, version: "1.0.0", dependencies });
 				}
 				let success = false;
 				try {
@@ -213,7 +214,7 @@ describe("lib/factorio", function() {
 			let zip = new jszip();
 			zip.file("world/control.lua", "-- unknown\n");
 			let zipPath = path.join("temp", "test", "patch.zip");
-			await fs.outputFile(zipPath, await zip.generateAsync({type: "nodebuffer"}))
+			await fs.outputFile(zipPath, await zip.generateAsync({ type: "nodebuffer" }));
 
 			await assert.rejects(
 				factorio.patch(zipPath, []),
diff --git a/test/lib/factorio/server.js b/test/lib/factorio/server.js
index a004f488..f42438e0 100644
--- a/test/lib/factorio/server.js
+++ b/test/lib/factorio/server.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const events = require("events");
 const fs = require("fs-extra");
@@ -84,7 +85,7 @@ describe("lib/factorio/server", function() {
 
 	describe("randomDynamicPort()", function() {
 		it("should return a port number", function() {
-			let port = factorio._randomDynamicPort()
+			let port = factorio._randomDynamicPort();
 			assert.equal(typeof port, "number");
 			assert(Number.isInteger(port));
 			assert(0 <= port && port < 2**16);
@@ -92,7 +93,7 @@ describe("lib/factorio/server", function() {
 
 		it("should return a port number in the dynamic range", function() {
 			function validate(port) {
-				return 49152 <= port && port <= 65535;
+				return (49152 <= port && port <= 65535);
 			}
 			for (let i=0; i < 20; i++) {
 				assert(validate(factorio._randomDynamicPort()));
@@ -157,8 +158,8 @@ describe("lib/factorio/server", function() {
 	describe("parseOutput()", function() {
 		it("should parse the test lines", function() {
 			for (let [line, reference] of testLines) {
-				reference.source = 'test';
-				let output = factorio._parseOutput(line, 'test');
+				reference.source = "test";
+				let output = factorio._parseOutput(line, "test");
 				delete output.received;
 				assert.deepEqual(output, reference);
 			}
@@ -187,50 +188,50 @@ describe("lib/factorio/server", function() {
 
 		describe("._handleIpc()", function() {
 			it("should emit the correct ipc event", async function() {
-				let waiter = events.once(server, 'ipc-channel');
+				let waiter = events.once(server, "ipc-channel");
 				await server._handleIpc(Buffer.from('\f$ipc:channel?j"value"'));
 				let result = await waiter;
 				assert.equal(result[0], "value");
 			});
 			it("should handle special characters in channel name", async function() {
-				let waiter = events.once(server, 'ipc-$ ?\x00\x0a:');
+				let waiter = events.once(server, "ipc-$ ?\x00\x0a:");
 				await server._handleIpc(Buffer.from('\f$ipc:$ \\x3f\\x00\\x0a:?j"value"'));
 				let result = await waiter;
 				assert.equal(result[0], "value");
 			});
 			it("should throw on malformed ipc line", async function() {
 				await assert.rejects(
-					server._handleIpc(Buffer.from('\f$ipc:blah')),
+					server._handleIpc(Buffer.from("\f$ipc:blah")),
 					new Error('Malformed IPC line "\f$ipc:blah"')
 				);
-			})
+			});
 			it("should throw on unknown type", async function() {
 				await assert.rejects(
-					server._handleIpc(Buffer.from('\f$ipc:channel??')),
+					server._handleIpc(Buffer.from("\f$ipc:channel??")),
 					new Error("Unknown IPC type '?'")
 				);
-			})
+			});
 			it("should throw on unknown file type", async function() {
 				await assert.rejects(
-					server._handleIpc(Buffer.from('\f$ipc:channel?ffoo.invalid')),
+					server._handleIpc(Buffer.from("\f$ipc:channel?ffoo.invalid")),
 					new Error("Unknown IPC file format 'invalid'")
 				);
-			})
+			});
 			it("should throw on file name with slash", async function() {
 				await assert.rejects(
-					server._handleIpc(Buffer.from('\f$ipc:channel?fa/b')),
+					server._handleIpc(Buffer.from("\f$ipc:channel?fa/b")),
 					new Error("Invalid IPC file name 'a/b'")
 				);
-			})
+			});
 			it("should load and delete json file", async function() {
-				let filePath = server.writePath('script-output', 'data.json');
+				let filePath = server.writePath("script-output", "data.json");
 				await fs.outputFile(filePath, '{"data":"spam"}');
-				let waiter = events.once(server, 'ipc-channel');
-				await server._handleIpc(Buffer.from('\f$ipc:channel?fdata.json'));
+				let waiter = events.once(server, "ipc-channel");
+				await server._handleIpc(Buffer.from("\f$ipc:channel?fdata.json"));
 				let result = await waiter;
 				assert.deepEqual(result[0], { "data": "spam" });
 				assert(!await fs.pathExists(filePath), "File was not deleted");
-			})
+			});
 		});
 	});
 });
diff --git a/test/lib/fileOps/fileOps.js b/test/lib/fileOps/fileOps.js
index d507b1ab..30744860 100644
--- a/test/lib/fileOps/fileOps.js
+++ b/test/lib/fileOps/fileOps.js
@@ -1,8 +1,9 @@
-const assert = require('assert').strict;
-const fs = require('fs-extra');
-const path = require('path');
+"use strict";
+const assert = require("assert").strict;
+const fs = require("fs-extra");
+const path = require("path");
 
-const fileOps = require('lib/fileOps');
+const fileOps = require("lib/fileOps");
 
 describe("fileOps.js", function(){
 	let baseDir = path.join("temp", "test", "fileOps");
diff --git a/test/lib/generateSSLcert.js b/test/lib/generateSSLcert.js
index 75f43b57..e64e6b43 100644
--- a/test/lib/generateSSLcert.js
+++ b/test/lib/generateSSLcert.js
@@ -1,10 +1,11 @@
+"use strict";
 const assert = require("assert");
 const fs = require("fs-extra");
 const path = require("path");
 
-const generateSSLcert = require("lib/generateSSLcert")
+const generateSSLcert = require("lib/generateSSLcert");
 
-describe("generateSSLcert.js(options)", ()=>{
+describe("generateSSLcert.js(options)", function() {
 	let testDir = path.join("temp", "test", "certTest");
 	before(async function() {
 		await fs.remove(testDir);
@@ -12,6 +13,7 @@ describe("generateSSLcert.js(options)", ()=>{
 
 	it("Creates a folder with a .crt and .key file in it", async function() {
 		this.timeout(1000);
+		// eslint-disable-next-line no-process-env
 		if (process.env.FAST_TEST) {
 			this.skip();
 		}
diff --git a/test/lib/hash.js b/test/lib/hash.js
index edcc5104..b12045d9 100644
--- a/test/lib/hash.js
+++ b/test/lib/hash.js
@@ -1,9 +1,10 @@
-const assert = require('assert').strict;
-const fs = require('fs');
-const path = require('path');
-const stream = require('stream');
+"use strict";
+const assert = require("assert").strict;
+const fs = require("fs");
+const path = require("path");
+const stream = require("stream");
 
-const hash = require('lib/hash');
+const hash = require("lib/hash");
 
 
 describe("lib/hash", function() {
diff --git a/test/lib/helpers.js b/test/lib/helpers.js
index e5586bd5..cdad02ad 100644
--- a/test/lib/helpers.js
+++ b/test/lib/helpers.js
@@ -1,17 +1,18 @@
+"use strict";
 const assert = require("assert").strict;
 
 const helpers = require("lib/helpers");
 
 
 describe("lib/helpers", function() {
-    describe("basicType()", function() {
-        it("should return the expected values", function() {
-            assert.equal(helpers.basicType("s"), "string");
-            assert.equal(helpers.basicType(null), "null");
-            assert.equal(helpers.basicType(undefined), "undefined");
-            assert.equal(helpers.basicType([1, 2]), "array");
-            assert.equal(helpers.basicType(7), "number");
-            assert.equal(helpers.basicType({ a: 1 }), "object");
-        });
-    });
+	describe("basicType()", function() {
+		it("should return the expected values", function() {
+			assert.equal(helpers.basicType("s"), "string");
+			assert.equal(helpers.basicType(null), "null");
+			assert.equal(helpers.basicType(undefined), "undefined");
+			assert.equal(helpers.basicType([1, 2]), "array");
+			assert.equal(helpers.basicType(7), "number");
+			assert.equal(helpers.basicType({ a: 1 }), "object");
+		});
+	});
 });
diff --git a/test/lib/link/connector.js b/test/lib/link/connector.js
index 6f0abb7c..4d650d67 100644
--- a/test/lib/link/connector.js
+++ b/test/lib/link/connector.js
@@ -1,8 +1,9 @@
-const assert = require('assert').strict;
-const events = require('events');
+"use strict";
+const assert = require("assert").strict;
+const events = require("events");
 
-const mock = require('../../mock');
-const link = require('lib/link');
+const mock = require("../../mock");
+const link = require("lib/link");
 
 
 describe("lib/link/connectors", function() {
@@ -33,7 +34,7 @@ describe("lib/link/connectors", function() {
 	});
 
 	describe("class WebSocketClientConnector", function() {
-		let testConnector = new link.WebSocketClientConnector('url', 1);
+		let testConnector = new link.WebSocketClientConnector("url", 1);
 		testConnector._socket = new mock.MockSocket();
 
 		describe(".register()", function() {
@@ -49,10 +50,10 @@ describe("lib/link/connectors", function() {
 			it("calls send on the socket", function() {
 				testConnector._state = "handshake";
 				testConnector._socket.sentMessages = [];
-				testConnector.sendHandshake('test', { test: true });
+				testConnector.sendHandshake("test", { test: true });
 				assert.deepEqual(
 					testConnector._socket.sentMessages.map(JSON.parse),
-					[{ seq: null, type: 'test', data: { test: true }}]
+					[{ seq: null, type: "test", data: { test: true }}]
 				);
 			});
 		});
@@ -61,10 +62,10 @@ describe("lib/link/connectors", function() {
 			it("calls send on the socket", function() {
 				testConnector._state = "connected";
 				testConnector._socket.sentMessages = [];
-				let seq = testConnector.send('test', { test: true });
+				let seq = testConnector.send("test", { test: true });
 				assert.deepEqual(
 					testConnector._socket.sentMessages.map(JSON.parse),
-					[{ seq, type: 'test', data: { test: true }}]
+					[{ seq, type: "test", data: { test: true }}]
 				);
 			});
 		});
@@ -80,19 +81,19 @@ describe("lib/link/connectors", function() {
 		describe(".processHandshake()", function() {
 			it("should close on invalid message", function() {
 				testConnector._socket.closeCalled = false;
-				testConnector._processHandshake({ data: "invalid message" }),
+				testConnector._processHandshake({ data: "invalid message" });
 				assert(testConnector._socket.closeCalled, "Close was not called on the socket");
 			});
 			it("should call register on hello", function() {
 				let called = false;
 				testConnector.register = () => { called = true; };
-				testConnector._processHandshake({ seq: 1, type: 'hello', data: { version: "test", plugins: {} }});
+				testConnector._processHandshake({ seq: 1, type: "hello", data: { version: "test", plugins: {} }});
 				assert(called, "register was not called");
 			});
 			it("should emit connect on ready", async function() {
 				let result = events.once(testConnector, "connect");
 				testConnector._processHandshake(
-					{ seq: 1, type: 'ready', data: { session_token: "x", heartbeat_interval: 10 }}
+					{ seq: 1, type: "ready", data: { session_token: "x", heartbeat_interval: 10 }}
 				);
 				await result;
 				clearInterval(testConnector._heartbeatId);
@@ -121,7 +122,7 @@ describe("lib/link/connectors", function() {
 			it("should emit message on message in connected state", async function() {
 				testConnector._socket.sentMessages = [];
 				testConnector._state = "connected";
-				let result = events.once(testConnector, 'message');
+				let result = events.once(testConnector, "message");
 				testConnector._socket.events.get("message")('{"message":true}');
 				assert.deepEqual(await result, [{ message: true }]);
 			});
diff --git a/test/lib/link/link.js b/test/lib/link/link.js
index 2091305f..9b860673 100644
--- a/test/lib/link/link.js
+++ b/test/lib/link/link.js
@@ -1,5 +1,6 @@
-const assert = require('assert').strict;
-const events = require('events');
+"use strict";
+const assert = require("assert").strict;
+const events = require("events");
 
 const link = require("lib/link");
 const errors = require("lib/errors");
@@ -14,13 +15,13 @@ describe("lib/link/link", function() {
 
 		before(function() {
 			testConnector = new mock.MockConnector();
-			testLink = new link.Link('source', 'target', testConnector);
-			testLink.setValidator('simple', schema.compile({
+			testLink = new link.Link("source", "target", testConnector);
+			testLink.setValidator("simple", schema.compile({
 				properties: {
 					"data": {
-						type: 'object',
+						type: "object",
 						properties: {
-							"string": { type: 'string' },
+							"string": { type: "string" },
 						},
 					},
 				},
@@ -28,20 +29,20 @@ describe("lib/link/link", function() {
 		});
 
 		it("should emitt error processing message to connector", async function() {
-			testLink.setHandler('throws', () => { throw new Error("Handler error"); }, () => true);
-			let result = events.once(testConnector, 'message');
-			testConnector.emit('message', { seq: 1, type: 'throws', data: {}});
+			testLink.setHandler("throws", () => { throw new Error("Handler error"); }, () => true);
+			let result = events.once(testConnector, "message");
+			testConnector.emit("message", { seq: 1, type: "throws", data: {}});
 			await assert.rejects(result, new Error("Handler error"));
 		});
 
 		describe(".setValidator()", function() {
 			it("should set the validator", function() {
-				testLink.setValidator('test', () => true);
-				assert(testLink._validators.has('test'), "validator was not added");
+				testLink.setValidator("test", () => true);
+				assert(testLink._validators.has("test"), "validator was not added");
 			});
 			it("should throw on duplicated validator", function() {
 				assert.throws(
-					() => testLink.setValidator('test', () => true),
+					() => testLink.setValidator("test", () => true),
 					new Error("test already has a validator")
 				);
 			});
@@ -50,18 +51,18 @@ describe("lib/link/link", function() {
 		describe(".setHandler()", function() {
 			it("should throw if validator is not passed", function() {
 				assert.throws(
-					() => testLink.setHandler('no_validator_test', (message) => {}),
+					() => testLink.setHandler("no_validator_test", (message) => {}),
 					new Error("validator is required")
 				);
 			});
 			it("should set the handler", function() {
-				let handler = (message) => {};
-				testLink.setHandler('handler_test', handler, (message) => true);
-				assert.equal(testLink._handlers.get('handler_test'), handler);
+				function handler(message) { }
+				testLink.setHandler("handler_test", handler, (message) => true);
+				assert.equal(testLink._handlers.get("handler_test"), handler);
 			});
 			it("should throw on duplicated handler", function() {
 				assert.throws(
-					() => testLink.setHandler('handler_test', (message) => {}),
+					() => testLink.setHandler("handler_test", (message) => {}),
 					new Error("handler_test already has a handler")
 				);
 			});
@@ -76,19 +77,19 @@ describe("lib/link/link", function() {
 			});
 			it("should throw on message without validator", function() {
 				assert.throws(
-					() => testLink.processMessage({ seq: 1, type: 'no_validator', data: {} }),
+					() => testLink.processMessage({ seq: 1, type: "no_validator", data: {} }),
 					new errors.InvalidMessage("No validator for no_validator on source-target")
 				);
 			});
 			it("should throw on message failing validation", function() {
 				assert.throws(
-					() => testLink.processMessage({ seq: 1, type: 'simple', data: { string: 1 }}),
+					() => testLink.processMessage({ seq: 1, type: "simple", data: { string: 1 }}),
 					{ message: "Validation failed for simple" }
 				);
 			});
 			it("should throw on unhandled message", function() {
 				assert.throws(
-					() => testLink.processMessage({ seq: 1, type: 'simple', data: { string: "a" }}),
+					() => testLink.processMessage({ seq: 1, type: "simple", data: { string: "a" }}),
 					new errors.InvalidMessage("Unhandled message simple")
 				);
 			});
@@ -97,16 +98,16 @@ describe("lib/link/link", function() {
 		describe("._processHandler()", function() {
 			it("should call the handler", function() {
 				let handled = [];
-				testLink.setHandler('handled', (message) => handled.push(message), (message) => true)
-				testLink._processHandler({ seq: 1, type: 'handled', data: { test: "foo" } });
-				assert.deepEqual(handled, [{ seq: 1, type: 'handled', data: { test: "foo" } }]);
+				testLink.setHandler("handled", (message) => handled.push(message), (message) => true);
+				testLink._processHandler({ seq: 1, type: "handled", data: { test: "foo" } });
+				assert.deepEqual(handled, [{ seq: 1, type: "handled", data: { test: "foo" } }]);
 			});
 			it("should return true if handled", function() {
-				let result = testLink._processHandler({ seq: 1, type: 'handled', data: {} });
+				let result = testLink._processHandler({ seq: 1, type: "handled", data: {} });
 				assert.equal(result, true);
 			});
 			it("should return false if not handled", function() {
-				let result = testLink._processHandler({ seq: 1, type: 'not_handled', data: {} });
+				let result = testLink._processHandler({ seq: 1, type: "not_handled", data: {} });
 				assert.equal(result, false);
 			});
 		});
@@ -114,62 +115,62 @@ describe("lib/link/link", function() {
 		describe("._processWaiters()", function() {
 			it("should call waiters", async function() {
 				let waiter = new Promise(resolve => {
-					testLink._waiters.set('test', [{ resolve, data: {} }]);
+					testLink._waiters.set("test", [{ resolve, data: {} }]);
 				});
 				assert(
-					testLink._processWaiters({ type: 'test', seq: 4, data: {} }),
+					testLink._processWaiters({ type: "test", seq: 4, data: {} }),
 					"Waiter was not processed"
 				);
-				assert.deepEqual(await waiter, { type: 'test', seq: 4, data: {} });
+				assert.deepEqual(await waiter, { type: "test", seq: 4, data: {} });
 			});
 			it("should filter on data", async function() {
 				let waiter = new Promise(resolve => {
-					testLink._waiters.set('test', [{ resolve, data: { a: 1, b: 2 } }]);
+					testLink._waiters.set("test", [{ resolve, data: { a: 1, b: 2 } }]);
 				});
 				assert(
-					!testLink._processWaiters({ type: 'test', seq: 4, data: {} }),
+					!testLink._processWaiters({ type: "test", seq: 4, data: {} }),
 					"Incorrectly matched empty message"
 				);
 				assert(
-					!testLink._processWaiters({ type: 'test', seq: 4, data: { a: 1, b: 0 } }),
+					!testLink._processWaiters({ type: "test", seq: 4, data: { a: 1, b: 0 } }),
 					"Incorrectly matched message with wrong data"
 				);
 				assert(
-					testLink._processWaiters({ type: 'test', seq: 4, data: { a: 1, b: 2, c: 3 } }),
+					testLink._processWaiters({ type: "test", seq: 4, data: { a: 1, b: 2, c: 3 } }),
 					"Did not match correct message"
 				);
-				assert.deepEqual(await waiter, { type: 'test', seq: 4, data: { a: 1, b: 2, c: 3 } });
+				assert.deepEqual(await waiter, { type: "test", seq: 4, data: { a: 1, b: 2, c: 3 } });
 			});
 		});
 
 		describe(".waitFor()", function() {
 			before(function() {
-				testLink.setValidator('waiter', (message) => true);
+				testLink.setValidator("waiter", (message) => true);
 			});
 
 			it("should throw on missing validator", async function() {
 				await assert.rejects(
-					testLink.waitFor('no_validator', {}),
+					testLink.waitFor("no_validator", {}),
 					new Error("No validator for no_validator on source-target")
 				);
 			});
 			it("should wait for a given message", async function() {
-				let result = testLink.waitFor('waiter', {});
+				let result = testLink.waitFor("waiter", {});
 				assert(
-					testLink._processWaiters({ type: 'waiter', seq: 5, data: {} }),
+					testLink._processWaiters({ type: "waiter", seq: 5, data: {} }),
 					"Did not proccess waiter"
 				);
-				assert.deepEqual(await result, { type: 'waiter', seq: 5, data: {} });
+				assert.deepEqual(await result, { type: "waiter", seq: 5, data: {} });
 			});
 			it("should handle multiple waiters", async function() {
-				let result1 = testLink.waitFor('waiter', {});
-				let result2 = testLink.waitFor('waiter', {});
+				let result1 = testLink.waitFor("waiter", {});
+				let result2 = testLink.waitFor("waiter", {});
 				assert(
-					testLink._processWaiters({ type: 'waiter', seq: 5, data: {} }),
+					testLink._processWaiters({ type: "waiter", seq: 5, data: {} }),
 					"Did not proccess waiter"
 				);
-				assert.deepEqual(await result1, { type: 'waiter', seq: 5, data: {} });
-				assert.deepEqual(await result2, { type: 'waiter', seq: 5, data: {} });
+				assert.deepEqual(await result1, { type: "waiter", seq: 5, data: {} });
+				assert.deepEqual(await result2, { type: "waiter", seq: 5, data: {} });
 			});
 		});
 	});
diff --git a/test/lib/link/messages.js b/test/lib/link/messages.js
index f1e3ebf6..25817638 100644
--- a/test/lib/link/messages.js
+++ b/test/lib/link/messages.js
@@ -1,21 +1,22 @@
-const assert = require('assert').strict;
+"use strict";
+const assert = require("assert").strict;
 
-const link = require('lib/link');
-const errors = require('lib/errors');
-const mock = require('../../mock');
+const link = require("lib/link");
+const errors = require("lib/errors");
+const mock = require("../../mock");
 
 
 describe("lib/link/messages", function() {
-	let testSourceLink = new link.Link('source', 'target', new mock.MockConnector());
-	let testTargetLink = new link.Link('target', 'source', new mock.MockConnector());
+	let testSourceLink = new link.Link("source", "target", new mock.MockConnector());
+	let testTargetLink = new link.Link("target", "source", new mock.MockConnector());
 
 	let lastTargetSent;
 	testTargetLink.send = (type, data) => { lastTargetSent = { type, data }; };
 
 	describe("class Request", function() {
 		let testRequest = new link.Request({
-			type: 'test',
-			links: ['source-target'],
+			type: "test",
+			links: ["source-target"],
 			requestProperties: {
 				"test": { type: "string" },
 			},
@@ -24,7 +25,7 @@ describe("lib/link/messages", function() {
 		describe("constructor", function() {
 			it("should throw on invalid forwardTo", function() {
 				assert.throws(
-					() => new link.Request({ links: [], forwardTo: 'invalid'}),
+					() => new link.Request({ links: [], forwardTo: "invalid" }),
 					new Error("Invalid forwardTo value invalid")
 				);
 			});
@@ -33,7 +34,7 @@ describe("lib/link/messages", function() {
 		describe(".attach()", function() {
 			it("should attach validator to a source link", function() {
 				testRequest.attach(testSourceLink);
-				assert(testSourceLink._validators.has('test_response'), "Validator was not set");
+				assert(testSourceLink._validators.has("test_response"), "Validator was not set");
 			});
 			it("should throw if missing handler on target link", function() {
 				assert.throws(
@@ -44,17 +45,17 @@ describe("lib/link/messages", function() {
 
 			let handlerResult;
 			it("should attach handler to a target link", function() {
-				testRequest.attach(testTargetLink, async (message) => handlerResult );
-				assert(testTargetLink._handlers.has('test_request'), "Handler was not set");
+				testRequest.attach(testTargetLink, async (message) => handlerResult);
+				assert(testTargetLink._handlers.has("test_request"), "Handler was not set");
 			});
 			it("should send result of calling the handler", async function() {
 				handlerResult = { test: "handler" };
-				testTargetLink._handlers.get('test_request')({ seq: 2 });
+				testTargetLink._handlers.get("test_request")({ seq: 2 });
 				let result = await new Promise(resolve => {
 					testTargetLink.connector.send = (type, data) => resolve({ type, data });
 				});
 				assert.deepEqual(result, {
-					type: 'test_response',
+					type: "test_response",
 					data: {
 						test: "handler",
 						seq: 2,
@@ -63,12 +64,12 @@ describe("lib/link/messages", function() {
 			});
 			it("should implicitly send an empty object on empty return", async function() {
 				handlerResult = undefined;
-				testTargetLink._handlers.get('test_request')({ seq: 2 });
+				testTargetLink._handlers.get("test_request")({ seq: 2 });
 				let result = await new Promise(resolve => {
 					testTargetLink.connector.send = (type, data) => resolve({ type, data });
 				});
 				assert.deepEqual(result, {
-					type: 'test_response',
+					type: "test_response",
 					data: {
 						seq: 2,
 					},
@@ -82,20 +83,16 @@ describe("lib/link/messages", function() {
 				testSourceLink.connector.send = (type, data) => {
 					request = { type, data };
 				};
-				testSourceLink.waitFor = (type, condition) => {
-					return { data: { type, request }};
-				};
+				testSourceLink.waitFor = (type, condition) => ({ data: { type, request }});
 				assert.deepEqual(
 					await testRequest.send(testSourceLink, { test: "request" }),
-					{ type: 'test_response', request: { type: 'test_request', data: {test: "request" }}}
+					{ type: "test_response", request: { type: "test_request", data: { test: "request" }}}
 				);
 				delete testSourceLink.connector.send;
 				delete testSourceLink.waitFor;
 			});
 			it("should throw error response", async function() {
-				testSourceLink.waitFor = (type, condition) => {
-					return { data: { error: "test error" }};
-				};
+				testSourceLink.waitFor = (type, condition) => ({ data: { error: "test error" }});
 				await assert.rejects(
 					testRequest.send(testSourceLink, { test: "blah" }),
 					new errors.RequestError("test error")
@@ -107,8 +104,8 @@ describe("lib/link/messages", function() {
 
 	describe("class Event", function() {
 		let testEvent = new link.Event({
-			type: 'test',
-			links: ['source-target'],
+			type: "test",
+			links: ["source-target"],
 			eventProperties: {
 				"test": { type: "string" },
 			},
@@ -117,13 +114,13 @@ describe("lib/link/messages", function() {
 		describe("constructor", function() {
 			it("should throw on invalid forwardTo", function() {
 				assert.throws(
-					() => new link.Event({ forwardTo: 'invalid'}),
+					() => new link.Event({ forwardTo: "invalid" }),
 					new Error("Invalid forwardTo value invalid")
 				);
 			});
 			it("should throw on invalid broadcastTo", function() {
 				assert.throws(
-					() => new link.Event({ broadcastTo: 'invalid'}),
+					() => new link.Event({ broadcastTo: "invalid" }),
 					new Error("Invalid broadcastTo value invalid")
 				);
 			});
@@ -139,7 +136,7 @@ describe("lib/link/messages", function() {
 			let called = false;
 			it("should attach handler and validator to a target link", function() {
 				testEvent.attach(testTargetLink, async (message) => { called = true; });
-				assert(testTargetLink._validators.has('test_event'), "Validator was not set");
+				assert(testTargetLink._validators.has("test_event"), "Validator was not set");
 			});
 			it("should call the attached event handler", function() {
 				testTargetLink._handlers.get("test_event")();
@@ -163,6 +160,6 @@ describe("lib/link/messages", function() {
 	describe("attachAllMessages()", function() {
 		it("does not throw", function() {
 			link.attachAllMessages(testSourceLink);
-		})
+		});
 	});
 });
diff --git a/test/lib/luaTools.js b/test/lib/luaTools.js
index c1dd8d36..c2958db1 100644
--- a/test/lib/luaTools.js
+++ b/test/lib/luaTools.js
@@ -1,6 +1,7 @@
-const assert = require('assert').strict;
+"use strict";
+const assert = require("assert").strict;
 
-const luaTools = require('lib/luaTools');
+const luaTools = require("lib/luaTools");
 
 
 describe("lib/luaTools", function() {
diff --git a/test/lib/objectOps.js b/test/lib/objectOps.js
index 5e591776..8ce2a769 100644
--- a/test/lib/objectOps.js
+++ b/test/lib/objectOps.js
@@ -1,32 +1,14 @@
-var assert = require('assert');
-var objectOps = require('lib/objectOps');
+"use strict";
+var assert = require("assert");
+var objectOps = require("lib/objectOps");
 
 describe("objectOps.js", function(){
-	/*describe("objectOps.clone()", function(){
-		it("clones javascript objects", function(){
-			var object1 = {hello:"world", cat:{legs:4, name:"Kitty", colors:["brown", "yellow", "purple"]}};
-			var object2 = {};
-			object2 = objectOps.clone(object1);
-			
-			assert.equal(object2.cat.name, object1.cat.name)
-			assert.equal(object1.hello, object2.hello)
-		});	
-		it("does not deep clone objects", function(){
-			var obj1 = {hello:"world", cat:{legs:4, name:"Kitty", colors:["brown", "yellow", "purple"]}};
-			var obj2 = {};
-			obj2 = objectOps.clone(obj1);
-			
-			obj1.cat.colors = "black";
-			assert.equal(obj1.cat.colors, "black");
-			assert.notEqual(obj2.cat.colors[1], "yellow");
-		});
-	});*/
 	describe("objectOps.deepclone()", function(){
 		it("deep clones javascript objects", function(){
-			var obj1 = {hello:"world", cat:{legs:4, name:"Kitty", colors:["brown", "yellow", "purple"]}};
+			var obj1 = { hello: "world", cat: { legs: 4, name: "Kitty", colors: ["brown", "yellow", "purple"] }};
 			var obj2 = {};
 			obj2 = objectOps.deepclone(obj1);
-			
+
 			obj1.cat.colors = "black";
 			assert.equal(obj1.cat.colors, "black");
 			assert.equal(obj2.cat.colors[1], "yellow");
@@ -37,4 +19,4 @@ describe("objectOps.js", function(){
 			});
 		});
 	});
-});
\ No newline at end of file
+});
diff --git a/test/lib/plugin.js b/test/lib/plugin.js
index 3e147065..f1122edc 100644
--- a/test/lib/plugin.js
+++ b/test/lib/plugin.js
@@ -1,11 +1,12 @@
-const assert = require('assert').strict;
-const fs = require('fs-extra');
-const path = require('path');
+"use strict";
+const assert = require("assert").strict;
+const fs = require("fs-extra");
+const path = require("path");
 
-const mock = require('../mock');
-const link = require('lib/link');
-const plugin = require('lib/plugin');
-const errors = require('lib/errors');
+const mock = require("../mock");
+const link = require("lib/link");
+const plugin = require("lib/plugin");
+const errors = require("lib/errors");
 
 
 describe("lib/plugin", function() {
@@ -14,7 +15,7 @@ describe("lib/plugin", function() {
 		it("should be constructible", async function() {
 			instancePlugin = new plugin.BaseInstancePlugin();
 			await instancePlugin.init();
-		})
+		});
 		it("should define defaults for hooks", async function() {
 			await instancePlugin.onMetrics();
 			await instancePlugin.onStart();
@@ -23,7 +24,7 @@ describe("lib/plugin", function() {
 			await instancePlugin.onOutput({});
 			instancePlugin.onMasterConnectionEvent("connect");
 			await instancePlugin.onPrepareMasterDisconnect();
-		})
+		});
 	});
 
 	describe("class BaseMasterPlugin", function() {
@@ -31,38 +32,38 @@ describe("lib/plugin", function() {
 		it("should be constructible", async function() {
 			masterPlugin = new plugin.BaseMasterPlugin();
 			await masterPlugin.init();
-		})
+		});
 		it("should define defaults for hooks", async function() {
 			await masterPlugin.onInstanceStatusChanged({}, "running", "initialized");
 			await masterPlugin.onMetrics();
 			await masterPlugin.onShutdown();
 			masterPlugin.onSlaveConnectionEvent({}, "connect");
 			await masterPlugin.onPrepareSlaveDisconnect({});
-		})
+		});
 	});
 
 	describe("loadPluginInfos()", function() {
 		let baseDir = path.join("temp", "test", "plugin");
-		let emptyDir = path.join(baseDir, 'emptyDir');
-		let emptyPlugin = path.join(baseDir, 'emptyPlugin');
-		let testPlugin = path.join(baseDir, 'testPlugin');
-		let brokenPlugin = path.join(baseDir, 'brokenPlugin');
-		let invalidPlugin = path.join(baseDir, 'invalidPlugin');
+		let emptyDir = path.join(baseDir, "emptyDir");
+		let emptyPlugin = path.join(baseDir, "emptyPlugin");
+		let testPlugin = path.join(baseDir, "testPlugin");
+		let brokenPlugin = path.join(baseDir, "brokenPlugin");
+		let invalidPlugin = path.join(baseDir, "invalidPlugin");
 		before(async function() {
 			await fs.ensureDir(emptyDir);
-			await fs.ensureDir(path.join(emptyPlugin, 'empty'));
+			await fs.ensureDir(path.join(emptyPlugin, "empty"));
 
 			async function writePlugin(pluginPath, name, infoName = name) {
 				await fs.outputFile(
-					path.join(pluginPath, name, 'info.js'),
+					path.join(pluginPath, name, "info.js"),
 					`module.exports = { name: "${infoName}" };`
 				);
 			}
 
-			await writePlugin(testPlugin, 'test');
-			await writePlugin(brokenPlugin, 'broken');
-			await fs.outputFile(path.join(brokenPlugin, 'broken', 'info.js'), "Syntax Error");
-			await writePlugin(invalidPlugin, 'invalid', 'wrong');
+			await writePlugin(testPlugin, "test");
+			await writePlugin(brokenPlugin, "broken");
+			await fs.outputFile(path.join(brokenPlugin, "broken", "info.js"), "Syntax Error");
+			await writePlugin(invalidPlugin, "invalid", "wrong");
 		});
 
 		it("should return an empty array for an empty directory", async function() {
@@ -74,7 +75,7 @@ describe("lib/plugin", function() {
 		it("should discover test plugin", async function() {
 			assert.deepEqual(
 				await plugin.loadPluginInfos(testPlugin),
-				[{ name: 'test' }]
+				[{ name: "test" }]
 			);
 		});
 		it("should reject on broken plugin", async function() {
@@ -91,18 +92,18 @@ describe("lib/plugin", function() {
 		});
 
 		after(async function() {
-			await fs.unlink(path.join(brokenPlugin, 'broken', 'info.js'));
+			await fs.unlink(path.join(brokenPlugin, "broken", "info.js"));
 		});
 	});
 
 	describe("attachPluginMessages()", function() {
-		let mockLink = new link.Link('source', 'target', new mock.MockConnector());
+		let mockLink = new link.Link("source", "target", new mock.MockConnector());
 		let mockEvent = new link.Event({ type: "test:test", links: ["target-source"] });
 		it("should accept pluginInfo without messages", function() {
 			plugin.attachPluginMessages(mockLink, {}, null);
 		});
 		it("should attach handler for the given message", function() {
-			let mockEventEventHandler = function() {};
+			function mockEventEventHandler() { };
 			plugin.attachPluginMessages(mockLink, { name: "test", messages: { mockEvent }}, { mockEventEventHandler });
 			assert(mockLink._handlers.get("test:test_event"), "handler was not registered");
 		});
diff --git a/test/lib/prometheus.js b/test/lib/prometheus.js
index f959556b..d1602c47 100644
--- a/test/lib/prometheus.js
+++ b/test/lib/prometheus.js
@@ -1,6 +1,7 @@
-const assert = require('assert').strict;
+"use strict";
+const assert = require("assert").strict;
 
-const prometheus = require('lib/prometheus');
+const prometheus = require("lib/prometheus");
 
 
 describe("lib/prometheus", function() {
@@ -8,7 +9,7 @@ describe("lib/prometheus", function() {
 		let registry;
 		beforeEach(function() {
 			registry = new prometheus.CollectorRegistry();
-		})
+		});
 
 		describe(".register()", function() {
 			it("should register a collector", function() {
@@ -105,22 +106,22 @@ describe("lib/prometheus", function() {
 	describe("class Counter", function() {
 		let counter;
 		beforeEach(function() {
-			counter = new prometheus.Counter('test', "Help", { register: false });
+			counter = new prometheus.Counter("test", "Help", { register: false });
 		});
 
 		describe("constructor", function() {
 			it("should be initialized to 0", function() {
-				assert.equal(counter._values.get(''), 0);
+				assert.equal(counter._values.get(""), 0);
 			});
 		});
 		describe(".inc()", function() {
 			it("should increment the counter by 1 by default", function() {
 				counter.inc();
-				assert.equal(counter._values.get(''), 1);
+				assert.equal(counter._values.get(""), 1);
 			});
 			it("should increment the counter by specified value", function() {
 				counter.inc(3.2);
-				assert.equal(counter._values.get(''), 3.2);
+				assert.equal(counter._values.get(""), 3.2);
 			});
 			it("should throw if value is negative", function() {
 				assert.throws(
@@ -146,53 +147,53 @@ describe("lib/prometheus", function() {
 	describe("class Gauge", function() {
 		let gauge;
 		beforeEach(function() {
-			gauge = new prometheus.Gauge('test', "Help", { register: false });
+			gauge = new prometheus.Gauge("test", "Help", { register: false });
 		});
 
 		describe("constructor", function() {
 			it("should be initialized to 0", function() {
-				assert.equal(gauge._values.get(''), 0);
+				assert.equal(gauge._values.get(""), 0);
 			});
 		});
 		describe(".inc()", function() {
 			it("should increment the gauge by 1 by default", function() {
 				gauge.inc();
-				assert.equal(gauge._values.get(''), 1);
+				assert.equal(gauge._values.get(""), 1);
 			});
 			it("should increment the gauge by specified value", function() {
 				gauge.inc(3.2);
-				assert.equal(gauge._values.get(''), 3.2);
+				assert.equal(gauge._values.get(""), 3.2);
 			});
 			it("should decrement on negative value", function() {
 				gauge.inc(-2);
-				assert.equal(gauge._values.get(''), -2);
+				assert.equal(gauge._values.get(""), -2);
 			});
 		});
 		describe(".dec()", function() {
 			it("should decrement the gauge by 1 by default", function() {
 				gauge.dec();
-				assert.equal(gauge._values.get(''), -1);
+				assert.equal(gauge._values.get(""), -1);
 			});
 			it("should decrement the gauge by specified value", function() {
 				gauge.dec(3.2);
-				assert.equal(gauge._values.get(''), -3.2);
+				assert.equal(gauge._values.get(""), -3.2);
 			});
 			it("should increment on negative value", function() {
 				gauge.dec(-2);
-				assert.equal(gauge._values.get(''), 2);
+				assert.equal(gauge._values.get(""), 2);
 			});
 		});
 		describe(".set()", function() {
 			it("should set the gauge to the specified value", function() {
 				gauge.set(7);
-				assert.equal(gauge._values.get(''), 7);
+				assert.equal(gauge._values.get(""), 7);
 			});
 		});
 		describe(".setToCurrentTime()", function() {
 			it("should set the gauge to current unix time in seconds", function() {
 				gauge.setToCurrentTime();
 				assert(
-					Math.abs(gauge._values.get('') - Date.now() / 1000) < 1,
+					Math.abs(gauge._values.get("") - Date.now() / 1000) < 1,
 					"value set is not close to the current unix time"
 				);
 			});
@@ -208,17 +209,17 @@ describe("lib/prometheus", function() {
 							name, "Help", { register: false }
 						),
 						new Error(`Invalid name '${name}'`)
-					)
+					);
 				}
 			});
 			it("should throw on invalid label names", function() {
 				for (let name of ["", " ", "0a", "$a", "a:"]) {
 					assert.throws(
 						() => new prometheus.Gauge(
-							'test', "Help", { register: false, labels: [name] }
+							"test", "Help", { register: false, labels: [name] }
 						),
 						new Error(`Invalid label '${name}'`)
-					)
+					);
 				}
 			});
 			it("should throw on missing name", function() {
@@ -243,7 +244,7 @@ describe("lib/prometheus", function() {
 
 		describe(".get()", function() {
 			it("should return the current value", function() {
-				let gauge = new prometheus.Gauge('test', "Help", { register: false });
+				let gauge = new prometheus.Gauge("test", "Help", { register: false });
 				gauge.set(11);
 				assert.equal(gauge.get(), 11);
 			});
@@ -253,34 +254,34 @@ describe("lib/prometheus", function() {
 			let gauge;
 			beforeEach(function() {
 				gauge = new prometheus.Gauge(
-					'test', "Help", { register: false, labels: ['a', 'b'] }
+					"test", "Help", { register: false, labels: ["a", "b"] }
 				);
 			});
 			it("should require all labels set at creation", function() {
 				assert.throws(
-					() => gauge.labels({a: "1"}),
+					() => gauge.labels({ a: "1" }),
 					new Error("Missing label 'b'")
 				);
 				assert.throws(
-					() => gauge.labels({b: "1"}),
+					() => gauge.labels({ b: "1" }),
 					new Error("Missing label 'a'")
 				);
 				assert.throws(
-					() => gauge.labels({a: '1', b: '2', c: '3'}),
+					() => gauge.labels({ a: "1", b: "2", c: "3" }),
 					new Error("Extra label 'c'")
 				);
 				assert.throws(
-					() => gauge.labels('1'),
+					() => gauge.labels("1"),
 					new Error("Missing label 'b'")
 				);
 				assert.throws(
-					() => gauge.labels('1', '2', '3'),
+					() => gauge.labels("1", "2", "3"),
 					new Error("Extra positional label")
 				);
 			});
 			it("should throw if label value is not a string", function() {
 				assert.throws(
-					() => gauge.labels({a: "1", b: 2}),
+					() => gauge.labels({ a: "1", b: 2 }),
 					new Error("Expected value for label 'b' to be a string")
 				);
 				assert.throws(
@@ -289,39 +290,39 @@ describe("lib/prometheus", function() {
 				);
 			});
 			it("should initialize a value for the label set", function() {
-				gauge.labels({ a: '1', b: '2'});
+				gauge.labels({ a: "1", b: "2" });
 				assert(gauge._values.has('a="1",b="2"'), "value was not set");
-				gauge.labels('4', '5');
+				gauge.labels("4", "5");
 				assert(gauge._values.has('a="4",b="5"'), "value was not set");
 			});
 			it("should return a child supporting the usual methods", function() {
-				let child = gauge.labels({ a: '1', b: '2'});
+				let child = gauge.labels({ a: "1", b: "2" });
 				child.get();
 				child.inc();
 				child.dec();
 				child.setToCurrentTime();
-				child = gauge.labels('7', '8');
+				child = gauge.labels("7", "8");
 				child.get();
 				child.inc();
 				child.dec();
 				child.setToCurrentTime();
 			});
 			it("should return the same child for the same labels", function() {
-				let child = gauge.labels('1', '2');
-				assert.equal(gauge.labels('1', '2'), child);
+				let child = gauge.labels("1", "2");
+				assert.equal(gauge.labels("1", "2"), child);
 			});
 		});
 		describe(".remove()", function() {
 			it("should remove a label set created with .labels()", function() {
 				let gauge = new prometheus.Gauge(
-					'test', "Help", { register: false, labels: ['a', 'b'] }
+					"test", "Help", { register: false, labels: ["a", "b"] }
 				);
-				gauge.labels({ a: '1', b: '2'});
-				gauge.remove({ a: '1', b: '2'});
+				gauge.labels({ a: "1", b: "2" });
+				gauge.remove({ a: "1", b: "2" });
 				assert(!gauge._values.has('a="1",b="2"'), "value was not removed");
 			});
 			it("should throw when removing the empty label set", function() {
-				let gauge = new prometheus.Gauge('test', "Help", { register: false });
+				let gauge = new prometheus.Gauge("test", "Help", { register: false });
 				assert.throws(
 					() => gauge.remove({}), new Error("labels cannot be empty")
 				);
@@ -330,46 +331,46 @@ describe("lib/prometheus", function() {
 		describe(".removeAll()", function() {
 			it("should remove a label set created with .labels()", function() {
 				let gauge = new prometheus.Gauge(
-					'test', "Help", { register: false, labels: ['a', 'b'] }
+					"test", "Help", { register: false, labels: ["a", "b"] }
 				);
-				gauge.labels('1', '2');
-				gauge.labels('1', '3');
-				gauge.labels('4', '6');
-				gauge.removeAll({a: '1'});
-				assert(gauge._values.size <= 1, "Matching labels remained")
+				gauge.labels("1", "2");
+				gauge.labels("1", "3");
+				gauge.labels("4", "6");
+				gauge.removeAll({ a: "1" });
+				assert(gauge._values.size <= 1, "Matching labels remained");
 				assert(
 					gauge._values.has('a="4",b="6"'),
 					"Non-matching label was removed"
 				);
 			});
 			it("should throw when removing the empty label set", function() {
-				let gauge = new prometheus.Gauge('test', "Help", { register: false });
+				let gauge = new prometheus.Gauge("test", "Help", { register: false });
 				assert.throws(
 					() => gauge.removeAll({}), new Error("labels cannot be empty")
 				);
 			});
 			it("should handle special characters", function() {
 				let gauge = new prometheus.Gauge(
-					'test', "Help", { register: false, labels: ['a', 'b'] }
-				)
-				gauge.labels('x\\\\\n\"\"\n\\', '2');
-				gauge.removeAll({a: 'x\\\\\n\"\"\n\\'});
-				assert(gauge._values.size === 0, "Matching labels remained")
+					"test", "Help", { register: false, labels: ["a", "b"] }
+				);
+				gauge.labels('x\\\\\n\"\"\n\\', "2");
+				gauge.removeAll({ a: 'x\\\\\n\"\"\n\\' });
+				assert(gauge._values.size === 0, "Matching labels remained");
 			});
 		});
 		describe(".clear()", function() {
 			it("should remove all label sets created with .labels()", function() {
 				let gauge = new prometheus.Gauge(
-					'test', "Help", { register: false, labels: ['a', 'b'] }
+					"test", "Help", { register: false, labels: ["a", "b"] }
 				);
-				gauge.labels({ a: '1', b: '2'});
-				gauge.labels({ a: '3', b: '4'});
-				gauge.labels({ a: '5', b: '6'});
+				gauge.labels({ a: "1", b: "2" });
+				gauge.labels({ a: "3", b: "4" });
+				gauge.labels({ a: "5", b: "6" });
 				gauge.clear();
 				assert(gauge._values.size == 0, "values was not cleared");
 			});
 			it("should throw when used on an unlabled metric", function() {
-				let gauge = new prometheus.Gauge('test', "Help", { register: false });
+				let gauge = new prometheus.Gauge("test", "Help", { register: false });
 				assert.throws(
 					() => gauge.clear(), new Error("Cannot clear unlabeled metric")
 				);
@@ -381,7 +382,7 @@ describe("lib/prometheus", function() {
 		describe("processStartTimeSeconds", function() {
 			it("should give a close point in time", async function() {
 				this.skip(); // XXX Doesn't work in Clusterio's shared testing env
-				let results = []
+				let results = [];
 				let collector = prometheus.defaultCollectors.processStartTimeSeconds;
 				for await (let result of collector.collect()) {
 					results.push(result);
@@ -393,7 +394,7 @@ describe("lib/prometheus", function() {
 				);
 
 				assert(
-					Math.abs(results[0].samples.get('') - Date.now() / 1000) < 1,
+					Math.abs(results[0].samples.get("") - Date.now() / 1000) < 1,
 					"value set is not close to the current unix time"
 				);
 			});
@@ -401,7 +402,7 @@ describe("lib/prometheus", function() {
 		describe("processCpuSecondsTotal", function() {
 			it("should give a low value", async function() {
 				this.skip(); // XXX Doesn't work in Clusterio's shared testing env
-				let results = []
+				let results = [];
 				let collector = prometheus.defaultCollectors.processCpuSecondsTotal;
 				for await (let result of collector.collect()) {
 					results.push(result);
@@ -412,7 +413,7 @@ describe("lib/prometheus", function() {
 					"collector did not give exactly one result"
 				);
 
-				let value = results[0].samples.get('')
+				let value = results[0].samples.get("");
 				assert(
 					value < 5 && value > 0,
 					`process time is not between 0 and 5 seconds (${value})`
@@ -422,7 +423,7 @@ describe("lib/prometheus", function() {
 		describe("processResidentMemoryBytes", function() {
 			it("should give a low value", async function() {
 				this.skip(); // XXX Doesn't work in Clusterio's shared testing env
-				let results = []
+				let results = [];
 				let collector = prometheus.defaultCollectors.processResidentMemoryBytes;
 				for await (let result of collector.collect()) {
 					results.push(result);
@@ -433,7 +434,7 @@ describe("lib/prometheus", function() {
 					"collector did not give exactly one result"
 				);
 
-				let value = results[0].samples.get('')
+				let value = results[0].samples.get("");
 				assert(
 					value < 200e6 && value > 0,
 					`resident memory is not between 0 and 200 MB (${value})`
@@ -443,7 +444,7 @@ describe("lib/prometheus", function() {
 		describe("processHeapBytes", function() {
 			it("should give a low value", async function() {
 				this.skip(); // XXX Doesn't work in Clusterio's shared testing env
-				let results = []
+				let results = [];
 				let collector = prometheus.defaultCollectors.processHeapBytes;
 				for await (let result of collector.collect()) {
 					results.push(result);
@@ -454,7 +455,7 @@ describe("lib/prometheus", function() {
 					"collector did not give exactly one result"
 				);
 
-				let value = results[0].samples.get('')
+				let value = results[0].samples.get("");
 				assert(
 					value < 200e6 && value > 0,
 					`heap is not between 0 and 200 MB (${value})`
@@ -466,35 +467,35 @@ describe("lib/prometheus", function() {
 	describe("exposition()", function() {
 		it("should format simple metrics", async function() {
 			let registry = new prometheus.CollectorRegistry();
-			let counter = new prometheus.Counter('a', "Help", { register: false });
+			let counter = new prometheus.Counter("a", "Help", { register: false });
 			registry.register(counter);
-			let gauge = new prometheus.Gauge('b', "Help", { register: false });
+			let gauge = new prometheus.Gauge("b", "Help", { register: false });
 			registry.register(gauge);
 			let exposition = await prometheus.exposition(registry.collect());
 			assert.equal(
 				exposition,
-				'# HELP a Help\n' +
-				'# TYPE a counter\n' +
-				'a 0\n' +
-				'\n' +
-				'# HELP b Help\n' +
-				'# TYPE b gauge\n' +
-				'b 0\n'
+				"# HELP a Help\n" +
+				"# TYPE a counter\n" +
+				"a 0\n" +
+				"\n" +
+				"# HELP b Help\n" +
+				"# TYPE b gauge\n" +
+				"b 0\n"
 			);
 		});
 		it("should format labeled metrics", async function() {
 			let registry = new prometheus.CollectorRegistry();
 			let gauge = new prometheus.Gauge(
-				'test', "Help", { register: false, labels: ['a', 'b']}
+				"test", "Help", { register: false, labels: ["a", "b"] }
 			);
-			gauge.labels({a: '1', b: '2'});
-			gauge.labels({b: 'y', a: 'x'});
+			gauge.labels({ a: "1", b: "2" });
+			gauge.labels({ b: "y", a: "x" });
 			registry.register(gauge);
 			let exposition = await prometheus.exposition(registry.collect());
 			assert.equal(
 				exposition,
-				'# HELP test Help\n' +
-				'# TYPE test gauge\n' +
+				"# HELP test Help\n" +
+				"# TYPE test gauge\n" +
 				'test{a="1",b="2"} 0\n' +
 				'test{a="x",b="y"} 0\n'
 			);
@@ -502,17 +503,17 @@ describe("lib/prometheus", function() {
 		it("should format Infinity and NaN", async function() {
 			let registry = new prometheus.CollectorRegistry();
 			let gauge = new prometheus.Gauge(
-				'test', "Help", { register: false, labels: ['n']}
+				"test", "Help", { register: false, labels: ["n"] }
 			);
-			gauge.labels({n: '1'}).set(Infinity);
-			gauge.labels({n: '2'}).set(-Infinity);
-			gauge.labels({n: '3'}).set(NaN);
+			gauge.labels({ n: "1" }).set(Infinity);
+			gauge.labels({ n: "2" }).set(-Infinity);
+			gauge.labels({ n: "3" }).set(NaN);
 			registry.register(gauge);
 			let exposition = await prometheus.exposition(registry.collect());
 			assert.equal(
 				exposition,
-				'# HELP test Help\n' +
-				'# TYPE test gauge\n' +
+				"# HELP test Help\n" +
+				"# TYPE test gauge\n" +
 				'test{n="1"} +Inf\n' +
 				'test{n="2"} -Inf\n' +
 				'test{n="3"} NaN\n'
@@ -521,11 +522,11 @@ describe("lib/prometheus", function() {
 	});
 
 	let serializedResult = {
-		metric: { type: 'type', name: 'name', help: "Help", labels: ['a', 'b'] },
-		samples: [ ['a="1",b="2"', 1], ['a="3",b="4"', 5], ]
+		metric: { type: "type", name: "name", help: "Help", labels: ["a", "b"] },
+		samples: [['a="1",b="2"', 1], ['a="3",b="4"', 5]],
 	};
 	let deserializedResult = {
-		metric: new prometheus.Metric('type', 'name', "Help", ['a', 'b']),
+		metric: new prometheus.Metric("type", "name", "Help", ["a", "b"]),
 		samples: new Map([['a="1",b="2"', 1], ['a="3",b="4"', 5]]),
 	};
 	describe("serializeResult()", function() {
@@ -533,26 +534,26 @@ describe("lib/prometheus", function() {
 			assert.deepEqual(
 				prometheus.serializeResult(deserializedResult),
 				serializedResult
-			)
+			);
 		});
 		it("should support adding labels", function() {
 			assert.deepEqual(
 				prometheus.serializeResult({
-					metric: new prometheus.Metric('type', 'name', "Help"),
-					samples: new Map([['', 2]]),
-				}, { addLabels: { c: '8' }}),
+					metric: new prometheus.Metric("type", "name", "Help"),
+					samples: new Map([["", 2]]),
+				}, { addLabels: { c: "8" }}),
 				{
-					metric: {type: 'type', name: 'name', help: "Help", labels: ['c']},
+					metric: { type: "type", name: "name", help: "Help", labels: ["c"] },
 					samples: [['c="8"', 2]],
 				}
 			);
 			assert.deepEqual(
 				prometheus.serializeResult({
-					metric: new prometheus.Metric('type', 'name', "Help", ['a']),
+					metric: new prometheus.Metric("type", "name", "Help", ["a"]),
 					samples: new Map([['a="4"', 3]]),
-				}, { addLabels: { c: '8' }}),
+				}, { addLabels: { c: "8" }}),
 				{
-					metric: {type: 'type', name: 'name', help: "Help", labels: ['a', 'c']},
+					metric: { type: "type", name: "name", help: "Help", labels: ["a", "c"] },
 					samples: [['a="4",c="8"', 3]],
 				}
 			);
@@ -560,30 +561,30 @@ describe("lib/prometheus", function() {
 		it("should support redefining name and help", function() {
 			assert.deepEqual(
 				prometheus.serializeResult({
-					metric: new prometheus.Metric('type', 'name', "Help"),
-					samples: new Map([['', 2]]),
-				}, { metricName: 'new', }),
+					metric: new prometheus.Metric("type", "name", "Help"),
+					samples: new Map([["", 2]]),
+				}, { metricName: "new" }),
 				{
-					metric: {type: 'type', name: 'new', help: "Help", labels: []},
-					samples: [['', 2]],
+					metric: { type: "type", name: "new", help: "Help", labels: [] },
+					samples: [["", 2]],
 				}
 			);
 			assert.deepEqual(
 				prometheus.serializeResult({
-					metric: new prometheus.Metric('type', 'name', "Help"),
-					samples: new Map([['', 2]]),
-				}, { metricHelp: "old", }),
+					metric: new prometheus.Metric("type", "name", "Help"),
+					samples: new Map([["", 2]]),
+				}, { metricHelp: "old" }),
 				{
-					metric: {type: 'type', name: 'name', help: "old", labels: []},
-					samples: [['', 2]],
+					metric: { type: "type", name: "name", help: "old", labels: [] },
+					samples: [["", 2]],
 				}
 			);
 		});
 		it("should throw on unrecoginzed option", function() {
 			assert.throws(
 				() => new prometheus.serializeResult({
-					metric: new prometheus.Metric('type', 'name', "Help"),
-					samples: new Map([['', 3]]),
+					metric: new prometheus.Metric("type", "name", "Help"),
+					samples: new Map([["", 3]]),
 				}, { invalid: true }),
 				new Error("Unrecognized option 'invalid'")
 			);
@@ -595,7 +596,7 @@ describe("lib/prometheus", function() {
 			assert.deepEqual(
 				prometheus.deserializeResult(serializedResult),
 				deserializedResult
-			)
+			);
 		});
 	});
 
diff --git a/test/lib/users.js b/test/lib/users.js
index 09c37f16..901bb53b 100644
--- a/test/lib/users.js
+++ b/test/lib/users.js
@@ -1,3 +1,4 @@
+"use strict";
 const assert = require("assert").strict;
 const users = require("lib/users");
 
diff --git a/test/master.js b/test/master.js
index 0c985e0a..128f106e 100644
--- a/test/master.js
+++ b/test/master.js
@@ -1,8 +1,9 @@
-const assert = require('assert').strict;
+"use strict";
+const assert = require("assert").strict;
 
-const mock = require('./mock');
-const master = require('../master');
+const mock = require("./mock");
+const master = require("../master");
 
 
-describe('Master testing', function() {
+describe("Master testing", function() {
 });
diff --git a/test/missing.js b/test/missing.js
index 35e53b8d..4cdbc87c 100644
--- a/test/missing.js
+++ b/test/missing.js
@@ -1,5 +1,6 @@
 // These are libraries that does not have any units test, they are
 // required here in order to track coverage for them.
 
-require('lib/manager/modManager');
-require('lib/npmPostinstall.js');
+"use strict";
+require("lib/manager/modManager");
+require("lib/npmPostinstall.js");
diff --git a/test/mock.js b/test/mock.js
index f2354628..c919d57c 100644
--- a/test/mock.js
+++ b/test/mock.js
@@ -1,3 +1,4 @@
+"use strict";
 const events = require("events");
 
 const link = require("lib/link");
@@ -42,7 +43,7 @@ class MockConnector extends events.EventEmitter {
 	send(type, data) {
 		let message = { seq: this._seq, type, data };
 		this.sentMessages.push(message);
-		setImmediate(() => this.emit('send', message));
+		setImmediate(() => this.emit("send", message));
 		return this._seq++;
 	}
 }
@@ -55,27 +56,27 @@ class MockServer {
 
 	async sendRcon(command) {
 		this.rconCommands.push(command);
-		return this.rconCommandResults.get(command) || '';
+		return this.rconCommandResults.get(command) || "";
 	}
 }
 
 class MockInstance extends link.Link {
 	constructor() {
-		super('instance', 'slave', new MockConnector());
+		super("instance", "slave", new MockConnector());
 		this.server = new MockServer();
 		this.name = "test";
 		this.config = {
 			get: (name) => {
-				if (name === "instance.id") { return 7357 }
+				if (name === "instance.id") { return 7357; }
 				throw Error("Not implemented");
-			}
-		}
+			},
+		};
 	}
 }
 
 class MockSlave extends link.Link {
 	constructor() {
-		super('slave', 'master', new MockConnector());
+		super("slave", "master", new MockConnector());
 	}
 }
 
diff --git a/test/slave.js b/test/slave.js
index 1ce8ed1c..159d310a 100644
--- a/test/slave.js
+++ b/test/slave.js
@@ -1,6 +1,7 @@
-const assert = require('assert').strict;
-const path = require('path');
-const fs = require('fs-extra');
+"use strict";
+const assert = require("assert").strict;
+const path = require("path");
+const fs = require("fs-extra");
 
 const link = require("lib/link");
 const config = require("lib/config");
@@ -23,16 +24,16 @@ describe("Slave testing", function() {
 		describe(".name", function() {
 			it("should give the name of the instance", function() {
 				assert.equal(instance.name, "foo");
-			})
+			});
 		});
 
 		describe(".path()", function() {
 			it("should give the path when called without arguments", function() {
 				assert.equal(instance.path(), "dir");
-			})
+			});
 			it("should join path with arguments", function() {
 				assert.equal(instance.path("bar"), path.join("dir", "bar"));
-			})
+			});
 		});
 	});
 
@@ -65,19 +66,19 @@ describe("Slave testing", function() {
 		});
 
 		it("should throw on CON, PRN, AUX, NUL, COM1, LPT1", function() {
-			for (let bad of ['CON', 'PRN', 'AUX', 'NUL', 'COM1', 'LPT1']) {
+			for (let bad of ["CON", "PRN", "AUX", "NUL", "COM1", "LPT1"]) {
 				check(
-					bad, 'cannot be named any of . ..'
-					+' CON PRN AUX NUL COM1-9 and LPT1-9'
+					bad, "cannot be named any of . .."
+					+" CON PRN AUX NUL COM1-9 and LPT1-9"
 				);
 			}
 		});
 
 		it("should throw on . and ..", function() {
-			for (let bad of ['.', '..']) {
+			for (let bad of [".", ".."]) {
 				check(
-					bad, 'cannot be named any of . ..'
-					+' CON PRN AUX NUL COM1-9 and LPT1-9'
+					bad, "cannot be named any of . .."
+					+" CON PRN AUX NUL COM1-9 and LPT1-9"
 				);
 			}
 		});
@@ -93,7 +94,7 @@ describe("Slave testing", function() {
 		let discardingLogger = {
 			warning: function() { },
 			log: function() { },
-		}
+		};
 
 		let instance;
 		before(async function() {