diff --git a/exp_groups/controller.ts b/exp_groups/controller.ts
index a6034433..846fc0fd 100644
--- a/exp_groups/controller.ts
+++ b/exp_groups/controller.ts
@@ -1,15 +1,23 @@
-import { BaseControllerPlugin } from "@clusterio/controller";
+import { BaseControllerPlugin, type Controller } from "@clusterio/controller";
 import * as lib from "@clusterio/lib";
 import * as messages from "./messages.js";
 import * as path from "node:path";
 
+const loaded = new WeakMap<Controller, ControllerPlugin>();
+
 export class ControllerPlugin extends BaseControllerPlugin {
     groups!: lib.SubscribableDatastore<messages.GroupRecord>;
     roleMappings!: lib.SubscribableDatastore<messages.RoleMappingRecord>;
     manualAssignments!: lib.SubscribableDatastore<messages.AssignmentRecord>;
     resolvedAssignments!: lib.SubscribableDatastore<messages.AssignmentRecord>;
 
+    /** The plugin loaded on a controller, for the exp_scenario seed. */
+    static get(controller: Controller) {
+        return loaded.get(controller);
+    }
+
     async init() {
+        loaded.set(this.controller, this);
         const databaseDirectory = this.controller.config.get("controller.database_directory");
 
         this.groups = new lib.SubscribableDatastore(
diff --git a/exp_roles/controller.ts b/exp_roles/controller.ts
index 96acc167..6d5b46f5 100644
--- a/exp_roles/controller.ts
+++ b/exp_roles/controller.ts
@@ -1,12 +1,20 @@
-import { BaseControllerPlugin, InstanceRecord } from "@clusterio/controller";
+import { BaseControllerPlugin, InstanceRecord, type Controller } from "@clusterio/controller";
 import * as lib from "@clusterio/lib";
 import * as messages from "./messages.js";
 import * as path from "node:path";
 
+const loaded = new WeakMap<Controller, ControllerPlugin>();
+
 export class ControllerPlugin extends BaseControllerPlugin {
 	roleMeta!: lib.SubscribableDatastore<messages.RoleMetaRecord>;
 
+	/** The plugin loaded on a controller, for the exp_scenario seed. */
+	static get(controller: Controller) {
+		return loaded.get(controller);
+	}
+
 	async init() {
+		loaded.set(this.controller, this);
 		const databaseDirectory = this.controller.config.get("controller.database_directory");
 
 		this.roleMeta = new lib.SubscribableDatastore(
diff --git a/exp_scenario/controller.ts b/exp_scenario/controller.ts
index e76d0c8e..cd19bd96 100644
--- a/exp_scenario/controller.ts
+++ b/exp_scenario/controller.ts
@@ -1,9 +1,9 @@
 import * as lib from "@clusterio/lib";
 import { BaseControllerPlugin } from "@clusterio/controller";
-import { RoleMetaRecord, type ControllerPlugin as RolesPlugin } from "@expcluster/roles";
-import {
-	GroupRecord, GroupPermissions, RoleMappingRecord, type ControllerPlugin as GroupsPlugin,
-} from "@expcluster/permission-groups";
+import { RoleMetaRecord } from "@expcluster/roles";
+import { GroupRecord, GroupPermissions, RoleMappingRecord } from "@expcluster/permission-groups";
+import { ControllerPlugin as RolesPlugin } from "@expcluster/roles/dist/node/controller.js";
+import { ControllerPlugin as GroupsPlugin } from "@expcluster/permission-groups/dist/node/controller.js";
 import * as messages from "./messages.js";
 import { SeedRole, SeedGroup, seedRoles, seedGroups, flattenSeedPermissions } from "./seed.js";
 
@@ -19,10 +19,8 @@ export class ControllerPlugin extends BaseControllerPlugin {
 	 * permissions, groups which already exist by name are reset to the seed.
 	 */
 	async handleSeedRequest() {
-		throw new lib.RequestError("Seeding is temporarily disabled, please contact the server administrator to seed the roles and groups");
-		/*
-		const rolesPlugin = this.controller.plugins.get("exp_roles") as RolesPlugin | undefined;
-		const groupsPlugin = this.controller.plugins.get("exp_groups") as GroupsPlugin | undefined;
+		const rolesPlugin = RolesPlugin.get(this.controller);
+		const groupsPlugin = GroupsPlugin.get(this.controller);
 		if (!rolesPlugin || !groupsPlugin) {
 			throw new lib.RequestError("Seeding requires the exp_roles and exp_groups plugins");
 		}
@@ -54,7 +52,6 @@ export class ControllerPlugin extends BaseControllerPlugin {
 
 		this.seedRoleMappings(groupsPlugin, roleIds, groupIds);
 		this.logger.info(`Seeded ${roleIds.size} roles and ${groupIds.size} permission groups`);
-		*/
 	}
 
 	/** Find or create the clusterio role for a seed role, returns undefined if it has no role to use. */
diff --git a/exp_scenario/test/controller.test.js b/exp_scenario/test/controller.test.js
index d7b96add..097365ab 100644
--- a/exp_scenario/test/controller.test.js
+++ b/exp_scenario/test/controller.test.js
@@ -42,7 +42,6 @@ async function startPlugin(t2, { withPlugins = true } = {}) {
 		for (const [name, Plugin] of [["exp_roles", RolesPlugin], ["exp_groups", GroupsPlugin]]) {
 			const plugin = new Plugin({ name }, controller, undefined, logger);
 			await plugin.init();
-			controller.plugins.set(name, plugin);
 		}
 	}
 
@@ -65,7 +64,7 @@ t.test("class ControllerPlugin", t2 => {
 
 	t2.test(".handleSeedRequest() creates the roles and reuses them by name", async t3 => {
 		const { plugin, controller } = await startPlugin(t3);
-		const rolesPlugin = controller.plugins.get("exp_roles");
+		const rolesPlugin = RolesPlugin.get(controller);
 
 		await plugin.handleSeedRequest();
 		t3.strictSame(controller.roles.size, seedRoles.length, "every seed role exists");
@@ -80,7 +79,7 @@ t.test("class ControllerPlugin", t2 => {
 
 	t2.test(".handleSeedRequest() creates the groups and resets them by name", async t3 => {
 		const { plugin, controller } = await startPlugin(t3);
-		const groupsPlugin = controller.plugins.get("exp_groups");
+		const groupsPlugin = GroupsPlugin.get(controller);
 
 		await plugin.handleSeedRequest();
 		t3.strictSame(groupsPlugin.groups.size, seedGroups.length, "every seed group exists");
@@ -101,7 +100,7 @@ t.test("class ControllerPlugin", t2 => {
 
 	t2.test(".handleSeedRequest() maps each role onto its group by rank", async t3 => {
 		const { plugin, controller } = await startPlugin(t3);
-		const groupsPlugin = controller.plugins.get("exp_groups");
+		const groupsPlugin = GroupsPlugin.get(controller);
 
 		await plugin.handleSeedRequest();
 		const mapped = seedRoles.filter(role => role.group !== undefined);
@@ -123,7 +122,7 @@ t.test("class ControllerPlugin", t2 => {
 
 	t2.test(".handleSeedRequest() reuses mappings and keeps clear of other mappings", async t3 => {
 		const { plugin, controller } = await startPlugin(t3);
-		const groupsPlugin = controller.plugins.get("exp_groups");
+		const groupsPlugin = GroupsPlugin.get(controller);
 
 		groupsPlugin.roleMappings.set(new RoleMappingRecord(99, new Set([0, 1]), 5, 2, true));
 		await plugin.handleSeedRequest();