diff --git a/frontend/src/composables/useRouteFilters.test.ts b/frontend/src/composables/useRouteFilters.test.ts
new file mode 100644
index 000000000..8723f0c96
--- /dev/null
+++ b/frontend/src/composables/useRouteFilters.test.ts
@@ -0,0 +1,11 @@
+import {describe, it, expectTypeOf} from 'vitest'
+import {useRouteFilters, type UseRouteFiltersReturn} from './useRouteFilters'
+
+interface DummyFilters {foo: string}
+
+describe('useRouteFilters type inference', () => {
+	it('should infer return types based on filter interface', () => {
+		type Result = ReturnType<typeof useRouteFilters<DummyFilters>>
+		expectTypeOf<Result>().toEqualTypeOf<UseRouteFiltersReturn<DummyFilters>>()
+	})
+})
diff --git a/frontend/src/composables/useRouteFilters.ts b/frontend/src/composables/useRouteFilters.ts
index 65d9f8245..c1849f315 100644
--- a/frontend/src/composables/useRouteFilters.ts
+++ b/frontend/src/composables/useRouteFilters.ts
@@ -5,13 +5,19 @@ import equal from 'fast-deep-equal/es6'
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export type Filters = Record<string, any>
 
+export interface UseRouteFiltersReturn<CurrentFilters extends Filters> {
+	filters: Ref<CurrentFilters>
+	hasDefaultFilters: Ref<boolean>
+	setDefaultFilters: () => void
+}
+
 export function useRouteFilters<CurrentFilters extends Filters>(
 	route: Ref<RouteLocationNormalized>,
 	getDefaultFilters: (route: RouteLocationNormalized) => CurrentFilters,
 	routeToFilters: (route: RouteLocationNormalized) => CurrentFilters,
 	filtersToRoute: (filters: CurrentFilters) => RouteLocationRaw,
 	routeAllowList: RouteRecordName[] = [],
-) {
+) : UseRouteFiltersReturn<CurrentFilters> {
 	const router = useRouter()
 
 	const filters = ref<CurrentFilters>(routeToFilters(route.value))
diff --git a/frontend/src/views/project/helpers/useGanttFilters.ts b/frontend/src/views/project/helpers/useGanttFilters.ts
index 450a35f98..5a211b523 100644
--- a/frontend/src/views/project/helpers/useGanttFilters.ts
+++ b/frontend/src/views/project/helpers/useGanttFilters.ts
@@ -4,8 +4,8 @@ import type {RouteLocationNormalized, RouteLocationRaw} from 'vue-router'
 import {isoToKebabDate} from '@/helpers/time/isoToKebabDate'
 import {parseDateProp} from '@/helpers/time/parseDateProp'
 import {parseBooleanProp} from '@/helpers/time/parseBooleanProp'
-import {useRouteFilters} from '@/composables/useRouteFilters'
-import {useGanttTaskList} from './useGanttTaskList'
+import {useRouteFilters, type UseRouteFiltersReturn} from '@/composables/useRouteFilters'
+import {useGanttTaskList, type UseGanttTaskListReturn} from './useGanttTaskList'
 
 import type {IProject} from '@/modelTypes/IProject'
 import type {TaskFilterParams} from '@/services/taskCollection'
@@ -94,8 +94,8 @@ function ganttFiltersToApiParams(filters: GanttFilters): TaskFilterParams {
 }
 
 export type UseGanttFiltersReturn =
-	ReturnType<typeof useRouteFilters<GanttFilters>> &
-	ReturnType<typeof useGanttTaskList<GanttFilters>>
+	UseRouteFiltersReturn<GanttFilters> &
+	UseGanttTaskListReturn
 
 export function useGanttFilters(route: Ref<RouteLocationNormalized>, viewId: Ref<IProjectView['id']>): UseGanttFiltersReturn {
 	const {
diff --git a/frontend/src/views/project/helpers/useGanttTaskList.test.ts b/frontend/src/views/project/helpers/useGanttTaskList.test.ts
new file mode 100644
index 000000000..df010762d
--- /dev/null
+++ b/frontend/src/views/project/helpers/useGanttTaskList.test.ts
@@ -0,0 +1,14 @@
+import {describe, it, expectTypeOf} from 'vitest'
+import {useGanttTaskList, type UseGanttTaskListReturn} from './useGanttTaskList'
+import type {Filters} from '@/composables/useRouteFilters'
+
+interface TestFilters extends Filters {
+	projectId: number
+}
+
+describe('useGanttTaskList return type', () => {
+	it('should match interface', () => {
+		type Result = ReturnType<typeof useGanttTaskList<TestFilters>>
+		expectTypeOf<Result>().toEqualTypeOf<UseGanttTaskListReturn>()
+	})
+})
diff --git a/frontend/src/views/project/helpers/useGanttTaskList.ts b/frontend/src/views/project/helpers/useGanttTaskList.ts
index 443106310..3fe2bf3c2 100644
--- a/frontend/src/views/project/helpers/useGanttTaskList.ts
+++ b/frontend/src/views/project/helpers/useGanttTaskList.ts
@@ -1,4 +1,4 @@
-import {computed, ref, type Ref, shallowReactive, watch} from 'vue'
+import {computed, ref, type Ref, shallowReactive, watch, type ComputedRef} from 'vue'
 import {klona} from 'klona/lite'
 
 import type {Filters} from '@/composables/useRouteFilters'
@@ -12,13 +12,21 @@ import {error, success} from '@/message'
 import {useAuthStore} from '@/stores/auth'
 import type {IProjectView} from '@/modelTypes/IProjectView'
 
+export interface UseGanttTaskListReturn {
+	tasks: Ref<Map<ITask['id'], ITask>>
+	isLoading: ComputedRef<boolean>
+	loadTasks: () => Promise<void>
+	addTask: (task: Partial<ITask>) => Promise<ITask>
+	updateTask: (task: ITaskPartialWithId) => Promise<void>
+}
+
 // FIXME: unify with general `useTaskList`
 export function useGanttTaskList<F extends Filters>(
 	filters: Ref<F>,
 	filterToApiParams: (filters: F) => TaskFilterParams,
 	viewId: Ref<IProjectView['id']>,
 	loadAll: boolean = true,
-) {
+) : UseGanttTaskListReturn {
 	const taskCollectionService = shallowReactive(new TaskCollectionService())
 	const taskService = shallowReactive(new TaskService())
 	const authStore = useAuthStore()