diff --git a/packages/backend/src/remote/activitypub/db-resolver.ts b/packages/backend/src/remote/activitypub/db-resolver.ts
index 041cd929e..0a5f32be4 100644
--- a/packages/backend/src/remote/activitypub/db-resolver.ts
+++ b/packages/backend/src/remote/activitypub/db-resolver.ts
@@ -45,7 +45,7 @@ export function parseUri(value: string | IObject): UriParseResult {
 	}
 }
 
-export default class DbResolver {
+export class DbResolver {
 	constructor() {
 	}
 
diff --git a/packages/backend/src/remote/activitypub/kernel/accept/follow.ts b/packages/backend/src/remote/activitypub/kernel/accept/follow.ts
index 21e7c29ce..58249d2de 100644
--- a/packages/backend/src/remote/activitypub/kernel/accept/follow.ts
+++ b/packages/backend/src/remote/activitypub/kernel/accept/follow.ts
@@ -2,7 +2,7 @@ import { CacheableRemoteUser } from '@/models/entities/user.js';
 import accept from '@/services/following/requests/accept.js';
 import { relayAccepted } from '@/services/relay.js';
 import { IFollow } from '@/remote/activitypub/type.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 
 export default async (actor: CacheableRemoteUser, activity: IFollow): Promise<string> => {
 	// ※ activityはこっちから投げたフォローリクエストなので、activity.actorは存在するローカルユーザーである必要がある
diff --git a/packages/backend/src/remote/activitypub/kernel/block/index.ts b/packages/backend/src/remote/activitypub/kernel/block/index.ts
index e66ed2799..7095a36a5 100644
--- a/packages/backend/src/remote/activitypub/kernel/block/index.ts
+++ b/packages/backend/src/remote/activitypub/kernel/block/index.ts
@@ -1,7 +1,7 @@
 import block from '@/services/blocking/create.js';
 import { CacheableRemoteUser } from '@/models/entities/user.js';
 import { Users } from '@/models/index.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 import { IBlock } from '@/remote/activitypub/type.js';
 
 export default async (actor: CacheableRemoteUser, activity: IBlock): Promise<string> => {
diff --git a/packages/backend/src/remote/activitypub/kernel/delete/note.ts b/packages/backend/src/remote/activitypub/kernel/delete/note.ts
index 8be9153b6..15c1cba8b 100644
--- a/packages/backend/src/remote/activitypub/kernel/delete/note.ts
+++ b/packages/backend/src/remote/activitypub/kernel/delete/note.ts
@@ -2,7 +2,7 @@ import { CacheableRemoteUser } from '@/models/entities/user.js';
 import deleteNode from '@/services/note/delete.js';
 import { getApLock } from '@/misc/app-lock.js';
 import { deleteMessage } from '@/services/messages/delete.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 import { apLogger } from '@/remote/activitypub/logger.js';
 
 export default async function(actor: CacheableRemoteUser, uri: string): Promise<string> {
diff --git a/packages/backend/src/remote/activitypub/kernel/follow.ts b/packages/backend/src/remote/activitypub/kernel/follow.ts
index f5d551db8..8125b4606 100644
--- a/packages/backend/src/remote/activitypub/kernel/follow.ts
+++ b/packages/backend/src/remote/activitypub/kernel/follow.ts
@@ -1,7 +1,7 @@
 import { CacheableRemoteUser } from '@/models/entities/user.js';
 import follow from '@/services/following/create.js';
 import { IFollow } from '../type.js';
-import DbResolver from '../db-resolver.js';
+import { DbResolver } from '../db-resolver.js';
 
 export default async (actor: CacheableRemoteUser, activity: IFollow): Promise<string> => {
 	const dbResolver = new DbResolver();
diff --git a/packages/backend/src/remote/activitypub/kernel/reject/follow.ts b/packages/backend/src/remote/activitypub/kernel/reject/follow.ts
index 203e01ea9..bd3ad1660 100644
--- a/packages/backend/src/remote/activitypub/kernel/reject/follow.ts
+++ b/packages/backend/src/remote/activitypub/kernel/reject/follow.ts
@@ -3,7 +3,7 @@ import { remoteReject } from '@/services/following/reject.js';
 import { relayRejected } from '@/services/relay.js';
 import { Users } from '@/models/index.js';
 import { IFollow } from '../../type.js';
-import DbResolver from '../../db-resolver.js';
+import { DbResolver } from '../../db-resolver.js';
 
 export default async (actor: CacheableRemoteUser, activity: IFollow): Promise<string> => {
 	// ※ activityはこっちから投げたフォローリクエストなので、activity.actorは存在するローカルユーザーである必要がある
diff --git a/packages/backend/src/remote/activitypub/kernel/undo/accept.ts b/packages/backend/src/remote/activitypub/kernel/undo/accept.ts
index b3f227012..b4664cb4a 100644
--- a/packages/backend/src/remote/activitypub/kernel/undo/accept.ts
+++ b/packages/backend/src/remote/activitypub/kernel/undo/accept.ts
@@ -1,7 +1,7 @@
 import unfollow from '@/services/following/delete.js';
 import { CacheableRemoteUser } from '@/models/entities/user.js';
 import { Followings } from '@/models/index.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 import { IAccept } from '@/remote/activitypub/type.js';
 
 export default async (actor: CacheableRemoteUser, activity: IAccept): Promise<string> => {
diff --git a/packages/backend/src/remote/activitypub/kernel/undo/block.ts b/packages/backend/src/remote/activitypub/kernel/undo/block.ts
index fc6763673..ae1c9c0b6 100644
--- a/packages/backend/src/remote/activitypub/kernel/undo/block.ts
+++ b/packages/backend/src/remote/activitypub/kernel/undo/block.ts
@@ -2,7 +2,7 @@ import unblock from '@/services/blocking/delete.js';
 import { CacheableRemoteUser } from '@/models/entities/user.js';
 import { Users } from '@/models/index.js';
 import { IBlock } from '@/remote/activitypub/type.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 
 export default async (actor: CacheableRemoteUser, activity: IBlock): Promise<string> => {
 	const dbResolver = new DbResolver();
diff --git a/packages/backend/src/remote/activitypub/kernel/undo/follow.ts b/packages/backend/src/remote/activitypub/kernel/undo/follow.ts
index 418eb5255..b2607351a 100644
--- a/packages/backend/src/remote/activitypub/kernel/undo/follow.ts
+++ b/packages/backend/src/remote/activitypub/kernel/undo/follow.ts
@@ -3,7 +3,7 @@ import cancelRequest from '@/services/following/requests/cancel.js';
 import { CacheableRemoteUser } from '@/models/entities/user.js';
 import { FollowRequests, Followings } from '@/models/index.js';
 import { IFollow } from '@/remote/activitypub/type.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 
 export default async (actor: CacheableRemoteUser, activity: IFollow): Promise<string> => {
 	const dbResolver = new DbResolver();
diff --git a/packages/backend/src/remote/activitypub/models/note.ts b/packages/backend/src/remote/activitypub/models/note.ts
index f025e12f4..fa2e2d04d 100644
--- a/packages/backend/src/remote/activitypub/models/note.ts
+++ b/packages/backend/src/remote/activitypub/models/note.ts
@@ -19,7 +19,7 @@ import { fromHtml } from '@/mfm/from-html.js';
 import { shouldBlockInstance } from '@/misc/should-block-instance.js';
 import { parseAudience } from '../audience.js';
 import { IObject, getOneApId, getApId, getOneApHrefNullable, validPost, IPost, isEmoji, getApType } from '../type.js';
-import DbResolver from '../db-resolver.js';
+import { DbResolver } from '../db-resolver.js';
 import Resolver from '../resolver.js';
 import { apLogger } from '../logger.js';
 import { resolvePerson } from './person.js';
diff --git a/packages/backend/src/server/api/endpoints/ap/show.ts b/packages/backend/src/server/api/endpoints/ap/show.ts
index fc8fc89ac..64c87e347 100644
--- a/packages/backend/src/server/api/endpoints/ap/show.ts
+++ b/packages/backend/src/server/api/endpoints/ap/show.ts
@@ -1,6 +1,6 @@
 import { createPerson } from '@/remote/activitypub/models/person.js';
 import { createNote } from '@/remote/activitypub/models/note.js';
-import DbResolver from '@/remote/activitypub/db-resolver.js';
+import { DbResolver } from '@/remote/activitypub/db-resolver.js';
 import Resolver from '@/remote/activitypub/resolver.js';
 import { extractDbHost } from '@/misc/convert-host.js';
 import { Users, Notes } from '@/models/index.js';