diff --git a/backend/src/controllers/error-helper.ts b/backend/src/controllers/error-helper.ts
index dd4091c8..a902560f 100644
--- a/backend/src/controllers/error-helper.ts
+++ b/backend/src/controllers/error-helper.ts
@@ -1,4 +1,4 @@
-import { BadRequestException } from '../exceptions/bad-request-exception';
+import { BadRequestException } from '../exceptions/bad-request-exception.js';
 
 /**
  * Checks for the presence of required fields and throws a BadRequestException
diff --git a/backend/src/interfaces/student-request.ts b/backend/src/interfaces/student-request.ts
index bde840c9..12e56f0d 100644
--- a/backend/src/interfaces/student-request.ts
+++ b/backend/src/interfaces/student-request.ts
@@ -1,8 +1,8 @@
-import { mapToStudentDTO, StudentDTO } from './student';
-import { ClassJoinRequest, ClassJoinRequestStatus } from '../entities/classes/class-join-request.entity';
-import { getClassJoinRequestRepository } from '../data/repositories';
-import { Student } from '../entities/users/student.entity';
-import { Class } from '../entities/classes/class.entity';
+import { mapToStudentDTO, StudentDTO } from './student.js';
+import { ClassJoinRequest, ClassJoinRequestStatus } from '../entities/classes/class-join-request.entity.js';
+import { getClassJoinRequestRepository } from '../data/repositories.js';
+import { Student } from '../entities/users/student.entity.js';
+import { Class } from '../entities/classes/class.entity.js';
 
 export interface StudentRequestDTO {
     requester: StudentDTO;
diff --git a/backend/src/routes/student-join-requests.ts b/backend/src/routes/student-join-requests.ts
index de2d522b..7dda6a07 100644
--- a/backend/src/routes/student-join-requests.ts
+++ b/backend/src/routes/student-join-requests.ts
@@ -1,5 +1,5 @@
 import express from 'express';
-import { createStudentRequestHandler, deleteClassJoinRequestHandler, getStudentRequestHandler } from '../controllers/students';
+import { createStudentRequestHandler, deleteClassJoinRequestHandler, getStudentRequestHandler } from '../controllers/students.js';
 
 const router = express.Router({ mergeParams: true });
 
diff --git a/backend/src/services/classes.ts b/backend/src/services/classes.ts
index f14a3cb5..56d801f3 100644
--- a/backend/src/services/classes.ts
+++ b/backend/src/services/classes.ts
@@ -3,8 +3,8 @@ import { ClassDTO, mapToClassDTO } from '../interfaces/class.js';
 import { mapToStudentDTO, StudentDTO } from '../interfaces/student.js';
 import { mapToTeacherInvitationDTO, mapToTeacherInvitationDTOIds, TeacherInvitationDTO } from '../interfaces/teacher-invitation.js';
 import { getLogger } from '../logging/initalize.js';
-import { NotFoundException } from '../exceptions/not-found-exception';
-import { Class } from '../entities/classes/class.entity';
+import { NotFoundException } from '../exceptions/not-found-exception.js';
+import { Class } from '../entities/classes/class.entity.js';
 
 const logger = getLogger();