diff --git a/exp_roles/test/module/assignment.lua b/exp_roles/test/module/assignment.lua
index a774af5f..69cfb7b9 100644
--- a/exp_roles/test/module/assignment.lua
+++ b/exp_roles/test/module/assignment.lua
@@ -1,5 +1,5 @@
 --- Tests for the assignment methods of module/control.lua
-local Suite = ... --- @type Suite The suite this file adds its tests to, see env.lua
+local Suite = ... --- @type Suite<ExpRoles.TestEnv> The suite this file adds its tests to, see env.lua
 local test, check, eq, empty = Suite.test, Suite.check, Suite.eq, Suite.empty
 
 --- alice is a moderator and bob a regular, with changes sent to the controller
@@ -40,7 +40,7 @@ test(".assign() applies locally and is sent to the controller", function(env)
     }, "the change is announced")
     eq(env.sounds, { "bob:utility/achievement_unlocked" }, "the assign sound plays")
 
-    local sd = env.Roles._script_data()
+    local sd = env.script_data()
     eq(sd.local_players.bob, { moderator.id }, "the role is held locally")
     eq(sd.pending.bob, { moderator.id }, "the role is pending")
 
@@ -54,7 +54,16 @@ test(".assign() defaults the by player to game.player", function(env)
     local players = setup(env)
     game.player = players.alice
     env.R("Jail"):assign(players.bob, { silent = true })
-    eq(env.events[1].by_player_index, players.alice.index, "the acting player is game.player")
+    eq(env.events, {
+        {
+            name = env.Roles.events.on_player_roles_changed,
+            tick = 1,
+            player_index = players.bob.index,
+            by_player_index = players.alice.index,
+            assigned = { env.R("Jail").id },
+            unassigned = {},
+        },
+    }, "the acting player is game.player")
 end)
 
 test("receive_assignment_updates() releases the local hold once confirmed", function(env)
@@ -65,7 +74,7 @@ test("receive_assignment_updates() releases the local hold once confirmed", func
     empty(env.events, "a confirmation raises no events")
     empty(env.printed, "a confirmation announces nothing")
 
-    local sd = env.Roles._script_data()
+    local sd = env.script_data()
     check(sd.local_players.bob == nil and sd.pending.bob == nil, "the role is no longer held locally")
     check(env.R("Moderator"):has_player(players.bob), "the role is still held after confirmation")
 end)
@@ -113,7 +122,7 @@ test("reject_assignment() rolls the assignment back", function(env)
         },
     }, "the rollback raises the event")
 
-    local sd = env.Roles._script_data()
+    local sd = env.script_data()
     check(sd.local_players.alice == nil and sd.pending.alice == nil, "the rollback clears the local state")
 end)
 
@@ -124,7 +133,7 @@ test(".assign() with local_only never reaches the controller", function(env)
     empty(env.sent, "the assignment is not sent")
     check(regular:has_player(players.alice), "the role applies")
 
-    local sd = env.Roles._script_data()
+    local sd = env.script_data()
     check(sd.pending.alice == nil, "the role is not pending")
     eq(sd.local_players.alice, { regular.id }, "the role is held locally")
 
@@ -146,15 +155,31 @@ test(".assign() of a higher priority role suppresses the rest", function(env)
     check(not env.Roles.player_has_permission(players.alice, "exp_scenario.command.kill"), "permissions are lost")
     check(not env.Roles.player_has_permission(players.alice, "exp_scenario.gui.readme"), "the default role is lost")
     check(not env.Roles.player_outranks(players.alice, players.bob), "a jailed player no longer outranks")
-    eq(env.events[1].assigned, { jail.id }, "the event lists the jail role")
-    empty(env.events[1].unassigned, "the suppressed roles are not listed as unassigned")
+    eq(env.events, {
+        {
+            name = env.Roles.events.on_player_roles_changed,
+            tick = 1,
+            player_index = players.alice.index,
+            by_player_index = 0,
+            assigned = { jail.id },
+            unassigned = {},
+        },
+    }, "the event lists only the jail role")
 
     env.reset_log()
     jail:unassign(players.alice, { by_player_name = "<server>", silent = true })
     eq(Suite.sorted(Suite.names(env.Roles.get_player_roles(players.alice))), { "Moderator", "Player" },
         "unjail restores the roles")
-    empty(env.events[1].assigned, "the restored roles are not listed as assigned")
-    eq(env.events[1].unassigned, { jail.id }, "the unjail event lists the jail role")
+    eq(env.events, {
+        {
+            name = env.Roles.events.on_player_roles_changed,
+            tick = 1,
+            player_index = players.alice.index,
+            by_player_index = 0,
+            assigned = {},
+            unassigned = { jail.id },
+        },
+    }, "the unjail event lists only the jail role")
 end)
 
 test(".assign() ignores the server", function(env)
diff --git a/exp_roles/test/module/env.lua b/exp_roles/test/module/env.lua
index 5b612329..d4e3953a 100644
--- a/exp_roles/test/module/env.lua
+++ b/exp_roles/test/module/env.lua
@@ -47,7 +47,17 @@ for _, record in ipairs(role_records()) do
     role_ids[record.name] = record.id
 end
 
+--- The environment given to each test: the stubs extended with a fresh copy
+--- of the roles module and the fixture helpers
+--- @class ExpRoles.TestEnv : Stubs
+--- @field Roles ExpRoles A fresh copy of the roles module
+--- @field R fun(name: string): ExpRoles.Role Get a fixture role by name
+--- @field assignment fun(player_name: string, role_names: string[]): { name: string, role_ids: number[], is_deleted: boolean? }
+--- @field script_data fun(): ExpRoles.ScriptData The module's script data, for asserting on internal state
+--- @field initialise fun(assignments: table[]?) Load the standard fixture and the given assignments
+
 return Framework.suite(function(env)
+    --- @cast env ExpRoles.TestEnv
     env.Roles = assert(loadfile(plugin_root .. "/module/control.lua"))() --- @type ExpRoles
     env.Roles.on_server_startup()
 
@@ -70,6 +80,12 @@ return Framework.suite(function(env)
         return { name = player_name, role_ids = ids }
     end
 
+    --- The module's script data, for asserting on internal state
+    function env.script_data()
+        --- @diagnostic disable-next-line: access-invisible
+        return env.Roles._script_data()
+    end
+
     --- Load the standard fixture and the given assignments
     function env.initialise(assignments)
         env.Roles.initialise{
diff --git a/exp_roles/test/module/holders.lua b/exp_roles/test/module/holders.lua
index 6d5cdb16..a57c8cac 100644
--- a/exp_roles/test/module/holders.lua
+++ b/exp_roles/test/module/holders.lua
@@ -1,5 +1,5 @@
 --- Tests for listing and printing to the players who hold a role
-local Suite = ... --- @type Suite The suite this file adds its tests to, see test/lua/framework.lua
+local Suite = ... --- @type Suite<ExpRoles.TestEnv> The suite this file adds its tests to, see test/lua/framework.lua
 local test, check, eq = Suite.test, Suite.check, Suite.eq
 
 --- alice and dave are moderators with dave offline, zed has never joined
@@ -30,7 +30,7 @@ test(".get_player_names() counts a player in both lists once", function(env)
     env.R("Regular"):assign(players.alice, { silent = true, local_only = true })
     env.Roles.receive_assignment_updates{ env.assignment("alice", { "Moderator", "Regular" }) }
 
-    local sd = env.Roles._script_data()
+    local sd = env.script_data()
     check(sd.local_players.alice ~= nil and sd.synced_players.alice ~= nil, "the role is held in both lists")
     eq(Suite.sorted(env.R("Regular"):get_player_names()), { "alice", "bob" }, "the player is counted once")
 end)
diff --git a/exp_roles/test/module/lookup.lua b/exp_roles/test/module/lookup.lua
index e203fbc6..0efcf1b8 100644
--- a/exp_roles/test/module/lookup.lua
+++ b/exp_roles/test/module/lookup.lua
@@ -1,5 +1,5 @@
 --- Tests for the role lookup functions of module/control.lua
-local Suite = ... --- @type Suite The suite this file adds its tests to, see test/lua/framework.lua
+local Suite = ... --- @type Suite<ExpRoles.TestEnv> The suite this file adds its tests to, see test/lua/framework.lua
 local test, check, eq = Suite.test, Suite.check, Suite.eq
 
 test("get_role() returns the role with the given clusterio id", function(env)
diff --git a/exp_roles/test/module/players.lua b/exp_roles/test/module/players.lua
index 50513a30..c7e00257 100644
--- a/exp_roles/test/module/players.lua
+++ b/exp_roles/test/module/players.lua
@@ -1,5 +1,5 @@
 --- Tests for the player checks of module/control.lua
-local Suite = ... --- @type Suite The suite this file adds its tests to, see test/lua/framework.lua
+local Suite = ... --- @type Suite<ExpRoles.TestEnv> The suite this file adds its tests to, see test/lua/framework.lua
 local test, check, eq = Suite.test, Suite.check, Suite.eq
 
 --- alice is a moderator, bob is a regular, and carol has only the default role
diff --git a/exp_roles/test/module/sync.lua b/exp_roles/test/module/sync.lua
index 64daf581..dc04fcbd 100644
--- a/exp_roles/test/module/sync.lua
+++ b/exp_roles/test/module/sync.lua
@@ -1,16 +1,19 @@
 --- Tests for the sync entry points of module/control.lua
-local Suite = ... --- @type Suite The suite this file adds its tests to, see test/lua/framework.lua
+local Suite = ... --- @type Suite<ExpRoles.TestEnv> The suite this file adds its tests to, see test/lua/framework.lua
 local test, check, eq, empty = Suite.test, Suite.check, Suite.eq, Suite.empty
 
+--- The state given by the admin trigger, reset by setup for every test
+local admin_state = {} --- @type table<string, boolean>
+
 --- alice is a moderator and carol has only the default role, both connected
 local function setup(env)
     local players = {
         alice = env.add_player("alice"),
         carol = env.add_player("carol"),
     }
-    env.admin_state = {}
+    admin_state = {}
     env.Roles.define_permission_trigger("exp_scenario.player.admin", function(player, state)
-        env.admin_state[player.name] = state
+        admin_state[player.name] = state
     end)
     env.initialise{
         env.assignment("alice", { "Moderator" }),
@@ -22,10 +25,12 @@ end
 
 test("initialise() applies triggers and raises empty events", function(env)
     setup(env)
-    eq(env.admin_state, { alice = true, carol = false }, "triggers run for connected players")
+    eq(admin_state, { alice = true, carol = false }, "triggers run for connected players")
     eq(#env.events, 2, "the event is raised once per connected player")
-    empty(env.events[1].assigned, "the events assign nothing")
-    empty(env.events[1].unassigned, "the events unassign nothing")
+    for _, event in ipairs(env.events) do
+        empty(event.assigned, "the events assign nothing")
+        empty(event.unassigned, "the events unassign nothing")
+    end
     empty(env.printed, "initialise is silent")
     empty(env.sent, "initialise sends nothing")
     empty(env.sounds, "initialise plays no sounds")
@@ -44,7 +49,7 @@ test("initialise() is authoritative for pending roles", function(env)
     env.R("Moderator"):assign(players.carol)
     env.R("Jail"):assign(players.carol, { silent = true, local_only = true })
 
-    local sd = env.Roles._script_data()
+    local sd = env.script_data()
     eq(sd.pending.carol, { env.R("Moderator").id }, "the role is pending before initialise")
 
     env.reset_log()
@@ -73,13 +78,22 @@ test("receive_assignment_updates() applies controller changes", function(env)
     eq(env.printed, {
         { "exp-roles.game-message-assign", "carol", "Moderator", "<server>" },
     }, "the change is announced by the server")
-    check(env.admin_state.carol == true, "triggers follow the assignment")
+    check(admin_state.carol == true, "triggers follow the assignment")
 
     env.reset_log()
     env.Roles.receive_assignment_updates{ { name = "carol", role_ids = {}, is_deleted = true } }
     check(not env.R("Moderator"):has_player(players.carol), "a removal applies")
-    eq(env.events[1].unassigned, { env.R("Moderator").id }, "the removal raises the event")
-    check(env.admin_state.carol == false, "triggers follow the removal")
+    eq(env.events, {
+        {
+            name = env.Roles.events.on_player_roles_changed,
+            tick = 1,
+            player_index = players.carol.index,
+            by_player_index = 0,
+            assigned = {},
+            unassigned = { env.R("Moderator").id },
+        },
+    }, "the removal raises the event")
+    check(admin_state.carol == false, "triggers follow the removal")
 end)
 
 test("receive_assignment_updates() for players not on this map raises nothing", function(env)
@@ -99,7 +113,9 @@ test("receive_role_updates() applies to the holders", function(env)
     }
     check(env.R("Regular"):has_permission("exp_scenario.command.jail"), "the permission change applies")
     eq(#env.events, 2, "a role change raises for every connected player")
-    empty(env.events[1].assigned, "role change events are empty")
+    for _, event in ipairs(env.events) do
+        empty(event.assigned, "role change events are empty")
+    end
 
     env.Roles.receive_role_updates{
         { id = regular_id, name = "Regular", permissions = {}, meta = { id = 0, order = 3 }, is_deleted = true },
@@ -146,9 +162,13 @@ end)
 
 test("on_player_joined_game() runs the triggers", function(env)
     local players = setup(env)
-    env.admin_state.alice = nil
-    env.Roles.on_player_joined_game{ player_index = players.alice.index }
-    check(env.admin_state.alice ~= nil, "triggers run when a player joins")
+    admin_state.alice = nil
+    env.Roles.on_player_joined_game{
+        name = defines.events.on_player_joined_game,
+        tick = game.tick,
+        player_index = players.alice.index,
+    }
+    check(admin_state.alice ~= nil, "triggers run when a player joins")
 end)
 
 return Suite.run()
diff --git a/test/lua/framework.lua b/test/lua/framework.lua
index 9fc97207..c9918cd0 100644
--- a/test/lua/framework.lua
+++ b/test/lua/framework.lua
@@ -26,19 +26,21 @@ local function repr(value, depth)
 end
 
 --- Create a suite of tests, one is made per test file
---- @param extend_env fun(env: table): table Extends the stubs given to each test
+--- @generic T : Stubs
+--- @param extend_env fun(env: Stubs): T Extends the stubs given to each test
+--- @return Suite<T>
 function Framework.suite(extend_env)
-    --- @class Suite
+    --- @class Suite<T>
     local Suite = {
-        tests = {},   -- { name, fn } in declaration order
-        results = {}, -- { name, ok, detail? } accumulated across tests
+        tests = {},   --- @type { name: string, fn: fun(env: T) }[] In declaration order
+        results = {}, --- @type { name: string, ok: boolean, detail: string? }[] Accumulated across tests
     }
 
     local current_test --- @type string?
 
     --- Declare a named test, its function receives a fresh environment
     --- @param name string
-    --- @param fn fun(env: table)
+    --- @param fn fun(env: T)
     function Suite.test(name, fn)
         Suite.tests[#Suite.tests + 1] = { name = name, fn = fn }
     end
diff --git a/test/lua/stubs.lua b/test/lua/stubs.lua
index 3cc1b3a8..b18d13ef 100644
--- a/test/lua/stubs.lua
+++ b/test/lua/stubs.lua
@@ -51,11 +51,15 @@ end
 --- Create an independent set of stubs, installed as the lua globals
 function Stubs.new()
     --- @class Stubs
+    --- @field events table[] Events raised through script.raise_event, name and tick filled in
+    --- @field printed (LocalisedString | { to: string, [1]: LocalisedString })[] Messages from game.print and player.print
+    --- @field sent { channel: string, data: table }[] Payloads sent through the clusterio api
+    --- @field sounds string[] Sounds played to players, as "player:path"
     local stubs = {
-        events = {},  -- events raised through script.raise_event
-        printed = {}, -- game.print and player.print messages
-        sent = {},    -- payloads sent through the clusterio api
-        sounds = {},  -- sounds played to players
+        events = {},
+        printed = {},
+        sent = {},
+        sounds = {},
     }
 
     local next_event_id = 100
@@ -97,8 +101,12 @@ function Stubs.new()
     }, { "player" })
 
     --- Add a player to the stubbed game, indexes are assigned in join order
+    --- @param name string
+    --- @param is_connected boolean? Defaults to connected
+    --- @return Stubs.Player
     function stubs.add_player(name, is_connected)
         local index = #players_by_index + 1
+        --- @class Stubs.Player
         local player = Stubs.strict("LuaPlayer " .. name, {
             name = name,
             index = index,
@@ -118,6 +126,7 @@ function Stubs.new()
     end
 
     --- A player object which represents the server
+    --- @type Stubs.Player
     stubs.server = Stubs.strict("LuaPlayer <server>", { index = 0, name = "<server>" })
 
     --- Modules resolved by the stubbed require, add to them with extend_requires