diff --git a/packages/backend/test/misc/MockApResolverService.ts b/packages/backend/test/misc/MockApResolverService.ts
new file mode 100644
index 0000000000..c066c3c004
--- /dev/null
+++ b/packages/backend/test/misc/MockApResolverService.ts
@@ -0,0 +1,127 @@
+/*
+ * SPDX-FileCopyrightText: hazelnoot and other Sharkey contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { Inject, Injectable } from '@nestjs/common';
+import { MockResolver } from './mock-resolver.js';
+import type { Config } from '@/config.js';
+import type { MiMeta } from '@/models/Meta.js';
+import type {
+	UsersRepository,
+	NotesRepository,
+	PollsRepository,
+	NoteReactionsRepository,
+	FollowRequestsRepository,
+} from '@/models/_.js';
+import { ApResolverService } from '@/core/activitypub/ApResolverService.js';
+import { DI } from '@/di-symbols.js';
+import { UtilityService } from '@/core/UtilityService.js';
+import { SystemAccountService } from '@/core/SystemAccountService.js';
+import { ApRequestService } from '@/core/activitypub/ApRequestService.js';
+import { HttpRequestService } from '@/core/HttpRequestService.js';
+import { ApRendererService } from '@/core/activitypub/ApRendererService.js';
+import { ApDbResolverService } from '@/core/activitypub/ApDbResolverService.js';
+import { LoggerService } from '@/core/LoggerService.js';
+import { ApLogService } from '@/core/ApLogService.js';
+import { ApUtilityService } from '@/core/activitypub/ApUtilityService.js';
+import { CacheService } from '@/core/CacheService.js';
+import { bindThis } from '@/decorators.js';
+
+/**
+ * Mock implementation of ApResolverService to automatically provide a MockResolver to the entire test environment.
+ */
+@Injectable()
+export class MockApResolverService extends ApResolverService {
+	/**
+	 * Resolver that will be provided.
+	 */
+	public readonly resolver: MockResolver;
+
+	constructor(
+		@Inject(DI.config)
+		config: Config,
+
+		@Inject(DI.meta)
+		meta: MiMeta,
+
+		@Inject(DI.usersRepository)
+		usersRepository: UsersRepository,
+
+		@Inject(DI.notesRepository)
+		notesRepository: NotesRepository,
+
+		@Inject(DI.pollsRepository)
+		pollsRepository: PollsRepository,
+
+		@Inject(DI.noteReactionsRepository)
+		noteReactionsRepository: NoteReactionsRepository,
+
+		@Inject(DI.followRequestsRepository)
+		followRequestsRepository: FollowRequestsRepository,
+
+		utilityService: UtilityService,
+		systemAccountService: SystemAccountService,
+		apRequestService: ApRequestService,
+		httpRequestService: HttpRequestService,
+		apRendererService: ApRendererService,
+		apDbResolverService: ApDbResolverService,
+		loggerService: LoggerService,
+		apLogService: ApLogService,
+		apUtilityService: ApUtilityService,
+		cacheService: CacheService,
+	) {
+		super(
+			config,
+			meta,
+			usersRepository,
+			notesRepository,
+			pollsRepository,
+			noteReactionsRepository,
+			followRequestsRepository,
+			utilityService,
+			systemAccountService,
+			apRequestService,
+			httpRequestService,
+			apRendererService,
+			apDbResolverService,
+			loggerService,
+			apLogService,
+			apUtilityService,
+			cacheService,
+		);
+
+		this.resolver = new MockResolver(
+			this.config,
+			this.meta,
+			this.usersRepository,
+			this.notesRepository,
+			this.pollsRepository,
+			this.noteReactionsRepository,
+			this.followRequestsRepository,
+			this.utilityService,
+			this.systemAccountService,
+			this.apRequestService,
+			this.httpRequestService,
+			this.apRendererService,
+			this.apDbResolverService,
+			this.loggerService,
+			this.apLogService,
+			this.apUtilityService,
+			this.cacheService,
+		);
+	}
+
+	/**
+	 * Resets the mock to initial state.
+	 */
+	@bindThis
+	reset() {
+		this.resolver.clear();
+	}
+
+	@bindThis
+	createResolver(): MockResolver {
+		return this.resolver;
+	}
+}