diff --git a/backend/src/middleware/auth/checks/learning-object-auth-checks.ts b/backend/src/middleware/auth/checks/learning-object-auth-checks.ts
index 2aad56b7..af4d8289 100644
--- a/backend/src/middleware/auth/checks/learning-object-auth-checks.ts
+++ b/backend/src/middleware/auth/checks/learning-object-auth-checks.ts
@@ -1,8 +1,8 @@
 import { Language } from '@dwengo-1/common/util/language';
-import learningObjectService from '../../../services/learning-objects/learning-object-service';
-import { authorize } from '../auth';
-import { AuthenticatedRequest } from '../authenticated-request';
-import { AuthenticationInfo } from '../authentication-info';
+import learningObjectService from '../../../services/learning-objects/learning-object-service.js';
+import { authorize } from '../auth.js';
+import { AuthenticatedRequest } from '../authenticated-request.js';
+import { AuthenticationInfo } from '../authentication-info.js';
 
 export const onlyAdminsForLearningObject = authorize(async (auth: AuthenticationInfo, req: AuthenticatedRequest) => {
     const { hruid } = req.params;
diff --git a/backend/src/middleware/auth/checks/learning-path-auth-checks.ts b/backend/src/middleware/auth/checks/learning-path-auth-checks.ts
index 6d4ec438..033c6e79 100644
--- a/backend/src/middleware/auth/checks/learning-path-auth-checks.ts
+++ b/backend/src/middleware/auth/checks/learning-path-auth-checks.ts
@@ -1,8 +1,8 @@
 import { Language } from '@dwengo-1/common/util/language';
-import learningPathService from '../../../services/learning-paths/learning-path-service';
-import { authorize } from '../auth';
-import { AuthenticatedRequest } from '../authenticated-request';
-import { AuthenticationInfo } from '../authentication-info';
+import learningPathService from '../../../services/learning-paths/learning-path-service.js';
+import { authorize } from '../auth.js';
+import { AuthenticatedRequest } from '../authenticated-request.js';
+import { AuthenticationInfo } from '../authentication-info.js';
 
 export const onlyAdminsForLearningPath = authorize(async (auth: AuthenticationInfo, req: AuthenticatedRequest) => {
     const adminsForLearningPath = await learningPathService.getAdmins({
diff --git a/backend/src/services/learning-objects/learning-object-service.ts b/backend/src/services/learning-objects/learning-object-service.ts
index 9e94c49d..1cc3cb78 100644
--- a/backend/src/services/learning-objects/learning-object-service.ts
+++ b/backend/src/services/learning-objects/learning-object-service.ts
@@ -3,9 +3,9 @@ import { LearningObjectProvider } from './learning-object-provider.js';
 import { envVars, getEnvVar } from '../../util/envVars.js';
 import databaseLearningObjectProvider from './database-learning-object-provider.js';
 import { FilteredLearningObject, LearningObjectIdentifierDTO, LearningPathIdentifier } from '@dwengo-1/common/interfaces/learning-content';
-import { getLearningObjectRepository, getTeacherRepository } from '../../data/repositories';
-import { processLearningObjectZip } from './learning-object-zip-processing-service';
-import { LearningObject } from '../../entities/content/learning-object.entity';
+import { getLearningObjectRepository, getTeacherRepository } from '../../data/repositories.js';
+import { processLearningObjectZip } from './learning-object-zip-processing-service.js';
+import { LearningObject } from '../../entities/content/learning-object.entity.js';
 import { LearningObjectIdentifier } from '../../entities/content/learning-object-identifier.js';
 import { NotFoundException } from '../../exceptions/not-found-exception.js';
 
diff --git a/backend/src/services/learning-objects/learning-object-zip-processing-service.ts b/backend/src/services/learning-objects/learning-object-zip-processing-service.ts
index bef79e1c..8c7a7c89 100644
--- a/backend/src/services/learning-objects/learning-object-zip-processing-service.ts
+++ b/backend/src/services/learning-objects/learning-object-zip-processing-service.ts
@@ -1,10 +1,10 @@
 import unzipper from 'unzipper';
 import mime from 'mime-types';
-import { LearningObject } from '../../entities/content/learning-object.entity';
-import { getAttachmentRepository, getLearningObjectRepository } from '../../data/repositories';
-import { BadRequestException } from '../../exceptions/bad-request-exception';
+import { LearningObject } from '../../entities/content/learning-object.entity.js';
+import { getAttachmentRepository, getLearningObjectRepository } from '../../data/repositories.js';
+import { BadRequestException } from '../../exceptions/bad-request-exception.js';
 import { LearningObjectMetadata } from '@dwengo-1/common/interfaces/learning-content';
-import { DwengoContentType } from './processing/content-type';
+import { DwengoContentType } from './processing/content-type.js';
 
 const METADATA_PATH_REGEX = /.*[/^]metadata\.json$/;
 const CONTENT_PATH_REGEX = /.*[/^]content\.[a-zA-Z]*$/;