diff --git a/.github/pull_request_template.md b/.github/pull_request_template.md
index 6735583..7cf8fff 100644
--- a/.github/pull_request_template.md
+++ b/.github/pull_request_template.md
@@ -1,23 +1,27 @@
+# 📌 Pull Request Title
+
 ## Description
 
-<!-- Briefly describe the changes made in this PR -->
+<!-- Provide a brief summary of the changes in this PR. -->
 
-## Type of Change
+## Related Issues
 
-- [ ] Bug fix
-- [ ] New feature
-- [ ] Breaking change
-- [ ] Documentation update
+<!-- Link related issues using `Closes #issue_number` or `Fixes #issue_number` -->
 
-## Checklist
+## Changes Made
+
+- [ ] List key changes made in this PR.
+
+## How to Test
 
-- [ ] Lint passes (`npm run lint` in both backend and frontend)
-- [ ] Build passes (`npm run build` in both backend and frontend)
-- [ ] Tests pass (`npm run test` in backend)
-- [ ] E2E tests pass (`npm run test:e2e` in backend)
-- [ ] No new TypeScript errors
-- [ ] No console errors or warnings
+<!-- Describe how a reviewer can test these changes. -->
 
-## Related Issue
+## Screenshots (if applicable)
+
+<!-- Upload screenshots for UI-related changes. -->
+
+## Checklist
 
-Closes #<!-- issue number -->
\ No newline at end of file
+- [ ] My code follows the project's coding style.
+- [ ] I have tested these changes locally.
+- [ ] Documentation has been updated where necessary.
diff --git a/.github/workflows/PULL_REQUEST_TEMPLATE.md b/.github/workflows/PULL_REQUEST_TEMPLATE.md
new file mode 100644
index 0000000..0764e0f
--- /dev/null
+++ b/.github/workflows/PULL_REQUEST_TEMPLATE.md
@@ -0,0 +1,27 @@
+# 📌 Pull Request Title
+
+## Description
+
+<!-- Provide a brief summary of the changes in this PR. -->
+
+## Related Issues
+
+<!-- Link related issues using `Closes #issue_number` or `Fixes #issue_number` -->
+
+## Changes Made
+
+- [ ] List key changes made in this PR.
+
+## How to Test
+
+<!-- Describe how a reviewer can test these changes. -->
+
+## Screenshots (if applicable)
+
+<!-- Upload screenshots for UI-related changes. -->
+
+## Checklist
+
+- [ ] My code follows the project's coding style.
+- [ ] I have tested these changes locally.
+- [ ] Documentation has been updated where necessary.
\ No newline at end of file
diff --git a/backend/lint_output.txt b/backend/lint_output.txt
new file mode 100644
index 0000000..f007a0e
Binary files /dev/null and b/backend/lint_output.txt differ
diff --git a/backend/src/admin/admin-courses.controller.ts b/backend/src/admin/admin-courses.controller.ts
index ca7fcb5..c2a1914 100644
--- a/backend/src/admin/admin-courses.controller.ts
+++ b/backend/src/admin/admin-courses.controller.ts
@@ -27,6 +27,7 @@ import { UserRole } from '../users/entities/user.entity';
 import { CreateCourseDto } from '../courses/dto/create-course.dto';
 import { UpdateCourseDto } from '../courses/dto/update-course.dto';
 import { CourseResponseDto } from '../courses/dto/course-response.dto';
+import { LessonResponseDto } from '../lessons/dto/lesson-response.dto';
 import { ReorderLessonsDto } from './dto/reorder-lessons.dto';
 import { PaginatedResult } from '../common/services/pagination.service';
 
@@ -143,4 +144,43 @@ export class AdminCoursesController {
   async unpublish(@Param('id') id: string): Promise<CourseResponseDto> {
     return this.coursesService.unpublishCourse(id);
   }
+
+  @Get(':id/lessons')
+  @ApiOperation({ summary: 'List all lessons for a course (admin)' })
+  async findAllLessons(
+    @Param('id') courseId: string,
+    @Query('page') page = 1,
+    @Query('limit') limit = 10,
+  ): Promise<PaginatedResult<LessonResponseDto>> {
+    const result = await this.lessonsService.findAllByCoursePaginated(
+      courseId,
+      Number(page),
+      Number(limit),
+      false, // Fetch all regardless of published status
+    );
+    return {
+      ...result,
+      data: result.data.map((lesson) => new LessonResponseDto(lesson)),
+    };
+  }
+
+  @Patch(':id/lessons/:lessonId/publish')
+  @ApiOperation({ summary: 'Publish a lesson (admin)' })
+  async publishLesson(
+    @Param('id') courseId: string,
+    @Param('lessonId') lessonId: string,
+  ): Promise<LessonResponseDto> {
+    const lesson = await this.lessonsService.setPublished(lessonId, true);
+    return new LessonResponseDto(lesson);
+  }
+
+  @Patch(':id/lessons/:lessonId/unpublish')
+  @ApiOperation({ summary: 'Unpublish a lesson (admin)' })
+  async unpublishLesson(
+    @Param('id') courseId: string,
+    @Param('lessonId') lessonId: string,
+  ): Promise<LessonResponseDto> {
+    const lesson = await this.lessonsService.setPublished(lessonId, false);
+    return new LessonResponseDto(lesson);
+  }
 }
diff --git a/backend/src/admin/admin-dao.controller.ts b/backend/src/admin/admin-dao.controller.ts
index 902df73..a81be26 100644
--- a/backend/src/admin/admin-dao.controller.ts
+++ b/backend/src/admin/admin-dao.controller.ts
@@ -8,7 +8,6 @@ import {
   Query,
   Request,
   ParseIntPipe,
-  NotFoundException,
   BadRequestException,
 } from '@nestjs/common';
 import {
diff --git a/backend/src/analytics/analytics.controller.ts b/backend/src/analytics/analytics.controller.ts
index 87fad8f..6e8045f 100644
--- a/backend/src/analytics/analytics.controller.ts
+++ b/backend/src/analytics/analytics.controller.ts
@@ -6,10 +6,6 @@ import {
   ApiResponse,
   ApiBearerAuth,
 } from '@nestjs/swagger';
-import { Roles } from '../common/decorators/roles.decorator';
-import { JwtAuthGuard } from '../common/guards/jwt-auth.guard';
-import { RolesGuard } from '../common/guards/roles.guard';
-import { UserRole } from '../common/enums/user-role.enum';
 import { AnalyticsService } from './analytics.service';
 import {
   AnalyticsOverviewDto,
@@ -17,6 +13,10 @@ import {
   LearnerActivityPointDto,
   TopLearnerDto,
 } from './dto/analytics-response.dto';
+import { JwtAuthGuard } from '../common/guards/jwt-auth.guard';
+import { RolesGuard } from '../common/guards/roles.guard';
+import { Roles } from '../common/decorators/roles.decorator';
+import { UserRole } from '../common/enums/user-role.enum';
 
 @ApiTags('Analytics')
 @ApiBearerAuth('access-token')
diff --git a/backend/src/auth/dto/create-auth.dto.ts b/backend/src/auth/dto/create-auth.dto.ts
index a15de30..00ef00f 100644
--- a/backend/src/auth/dto/create-auth.dto.ts
+++ b/backend/src/auth/dto/create-auth.dto.ts
@@ -1,2 +1 @@
-import { ApiProperty } from '@nestjs/swagger';
 export class CreateAuthDto {}
diff --git a/backend/src/auth/dto/update-auth.dto.ts b/backend/src/auth/dto/update-auth.dto.ts
index 8415eae..100de4f 100644
--- a/backend/src/auth/dto/update-auth.dto.ts
+++ b/backend/src/auth/dto/update-auth.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateAuthDto } from './create-auth.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateAuthDto extends PartialType(CreateAuthDto) {}
diff --git a/backend/src/auth/strategies/jwt.strategy.ts b/backend/src/auth/strategies/jwt.strategy.ts
index 78ed9b9..ee6d809 100644
--- a/backend/src/auth/strategies/jwt.strategy.ts
+++ b/backend/src/auth/strategies/jwt.strategy.ts
@@ -18,7 +18,7 @@ export class JwtStrategy extends PassportStrategy(Strategy) {
     });
   }
 
-  async validate(payload: any) {
+  async validate(payload: { sub: string; email: string; role: string }) {
     const user = await this.userService.findById(payload.sub);
 
     if (!user) {
diff --git a/backend/src/certificates/certificates.service.spec.ts b/backend/src/certificates/certificates.service.spec.ts
index 1747b0e..2281a54 100644
--- a/backend/src/certificates/certificates.service.spec.ts
+++ b/backend/src/certificates/certificates.service.spec.ts
@@ -54,7 +54,6 @@ const makeUserRepo = () => ({
 const makeCourseRepo = () => ({
   findOneBy: jest.fn(),
 });
-
 describe('CertificateService', () => {
   let service: CertificateService;
   let certRepo: ReturnType<typeof makeCertRepo>;
diff --git a/backend/src/certificates/certificates.service.ts b/backend/src/certificates/certificates.service.ts
index a3719bf..7c6e175 100644
--- a/backend/src/certificates/certificates.service.ts
+++ b/backend/src/certificates/certificates.service.ts
@@ -326,18 +326,12 @@ export class CertificateService {
       certificateData,
     } = issueCertificateDto;
 
-    const hashPayload = {
-      recipientName,
-      recipientEmail,
-      courseOrProgram,
-      issuedAt,
-      timestamp: Date.now(),
-    };
+    const issuedAtDate = new Date(issuedAt);
 
     const certificateHash = this.generateCertificateHash(
       recipientName + recipientEmail,
       courseOrProgram,
-      new Date(issuedAt),
+      issuedAtDate,
     );
 
     const existing = await this.certificateRepository.findOne({
diff --git a/backend/src/certificates/dto/create-certificate.dto.ts b/backend/src/certificates/dto/create-certificate.dto.ts
index 6acc62d..df7f323 100644
--- a/backend/src/certificates/dto/create-certificate.dto.ts
+++ b/backend/src/certificates/dto/create-certificate.dto.ts
@@ -1,2 +1 @@
-import { ApiProperty } from '@nestjs/swagger';
 export class CreateCertificateDto {}
diff --git a/backend/src/certificates/dto/update-certificate.dto.ts b/backend/src/certificates/dto/update-certificate.dto.ts
index 2223238..bfd38a8 100644
--- a/backend/src/certificates/dto/update-certificate.dto.ts
+++ b/backend/src/certificates/dto/update-certificate.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateCertificateDto } from './create-certificate.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateCertificateDto extends PartialType(CreateCertificateDto) {}
diff --git a/backend/src/common/dto/paggination.dto.ts b/backend/src/common/dto/paggination.dto.ts
deleted file mode 100644
index 23e4eab..0000000
--- a/backend/src/common/dto/paggination.dto.ts
+++ /dev/null
@@ -1 +0,0 @@
-import { ApiProperty } from '@nestjs/swagger';
diff --git a/backend/src/courses/courses.controller.ts b/backend/src/courses/courses.controller.ts
index 58e8c96..bfde5b8 100644
--- a/backend/src/courses/courses.controller.ts
+++ b/backend/src/courses/courses.controller.ts
@@ -24,7 +24,6 @@ import { AuthGuard } from '@nestjs/passport';
 
 import { JwtAuthGuard } from '../common/guards/jwt-auth.guard';
 import { RolesGuard } from '../common/guards/roles.guard';
-import { PaginationDto } from '../common/dto/pagination.dto';
 import { CourseFilterDto } from './dto/course-filter.dto';
 import { CoursesService } from './courses.service';
 import { UserRole } from '../common/enums/user-role.enum';
diff --git a/backend/src/courses/courses.service.spec.ts b/backend/src/courses/courses.service.spec.ts
index f2d52a0..1697e70 100644
--- a/backend/src/courses/courses.service.spec.ts
+++ b/backend/src/courses/courses.service.spec.ts
@@ -5,9 +5,6 @@ import { CoursesService } from './courses.service';
 import { Course } from './entities/course.entity';
 import { CourseRegistration } from './entities/course-registration.entity';
 import { PaginationService } from '../common/services/pagination.service';
-import { Lesson } from '../lessons/entities/lesson.entity';
-import { Progress } from '../progress/entities/progress.entity';
-import { NotificationsService } from '../notifications/notifications.service';
 
 const now = new Date();
 
diff --git a/backend/src/courses/dto/course-response.dto.ts b/backend/src/courses/dto/course-response.dto.ts
index 4a95f9a..4a4e877 100644
--- a/backend/src/courses/dto/course-response.dto.ts
+++ b/backend/src/courses/dto/course-response.dto.ts
@@ -19,35 +19,46 @@ export class CourseResponseDto {
   @IsNotEmpty()
   id: string;
 
-  @ApiProperty()
+  @ApiProperty({ example: 'Intro to Blockchain', description: 'title field' })
   @IsString()
   @IsNotEmpty()
   title: string;
 
   @ApiProperty({
-    example: 'A concise description of the resource.',
+    example: 'A concise description of the course.',
     description: 'description field',
   })
   @IsString()
   @IsNotEmpty()
   description: string;
 
-  @ApiProperty()
+  @ApiProperty({ example: true, required: false })
   @IsBoolean()
-  published: boolean;
+  @IsOptional()
+  published?: boolean;
 
-  @ApiProperty({ example: 'Beginner', required: false, nullable: true })
+  @ApiProperty({
+    example: 'Beginner',
+    description: 'difficulty field',
+    required: false,
+    nullable: true,
+  })
   @IsOptional()
   @IsString()
   difficulty: string | null;
 
-  @ApiProperty({ example: ['bitcoin', 'defi'], type: [String] })
+  @ApiProperty({
+    example: ['blockchain', 'tech'],
+    description: 'tags field',
+    type: [String],
+  })
   @IsArray()
   @IsString({ each: true })
   tags: string[];
 
   @ApiProperty({
     example: 'https://example.com/thumb.jpg',
+    description: 'thumbnailUrl field',
     required: false,
     nullable: true,
   })
@@ -55,7 +66,7 @@ export class CourseResponseDto {
   @IsUrl()
   thumbnailUrl: string | null;
 
-  @ApiProperty({ example: 42, description: 'Number of enrolled users' })
+  @ApiProperty({ example: 120, description: 'enrollmentCount field' })
   @IsInt()
   enrollmentCount: number;
 
@@ -73,7 +84,6 @@ export class CourseResponseDto {
   @IsDate()
   updatedAt: Date;
 
-  /** Present on GET /courses when the request includes a valid JWT */
   @ApiProperty({
     example: true,
     description: 'isEnrolled field',
diff --git a/backend/src/courses/dto/create-course.dto.ts b/backend/src/courses/dto/create-course.dto.ts
index c75e500..5463289 100644
--- a/backend/src/courses/dto/create-course.dto.ts
+++ b/backend/src/courses/dto/create-course.dto.ts
@@ -14,10 +14,7 @@ export class CreateCourseDto {
   @IsNotEmpty()
   title: string;
 
-  @ApiProperty({
-    example: 'A concise description of the resource.',
-    description: 'description field',
-  })
+  @ApiProperty({ example: 'A concise description of the course.' })
   @IsString()
   @IsNotEmpty()
   description: string;
diff --git a/backend/src/courses/dto/update-course.dto.ts b/backend/src/courses/dto/update-course.dto.ts
index 09a7a74..26acf7b 100644
--- a/backend/src/courses/dto/update-course.dto.ts
+++ b/backend/src/courses/dto/update-course.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateCourseDto } from './create-course.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateCourseDto extends PartialType(CreateCourseDto) {}
diff --git a/backend/src/currencies/currencies.service.ts b/backend/src/currencies/currencies.service.ts
index 81306d2..4ee8da6 100644
--- a/backend/src/currencies/currencies.service.ts
+++ b/backend/src/currencies/currencies.service.ts
@@ -1,6 +1,6 @@
 import { Injectable, NotFoundException } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
-import { Repository, Like } from 'typeorm';
+import { Repository } from 'typeorm';
 import { CurrencyEntry, CurrencyType } from './entities/currency-entry.entity';
 import {
   CreateCurrencyDto,
@@ -43,7 +43,7 @@ export class CurrenciesService {
 
     const formattedItems = items.map((item) => {
       // Omit detailed historical data in find all list to reduce payload
-      const { historicalData, ...rest } = item;
+      const { historicalData: _historicalData, ...rest } = item;
       return rest;
     });
 
diff --git a/backend/src/lessons/dto/create-lesson.dto.ts b/backend/src/lessons/dto/create-lesson.dto.ts
index 814f581..155245d 100644
--- a/backend/src/lessons/dto/create-lesson.dto.ts
+++ b/backend/src/lessons/dto/create-lesson.dto.ts
@@ -6,6 +6,7 @@ import {
   IsNumber,
   Min,
   IsUrl,
+  IsBoolean,
 } from 'class-validator';
 import { ApiProperty } from '@nestjs/swagger';
 
@@ -30,7 +31,16 @@ export class CreateLessonDto {
   videoUrl?: string;
 
   @ApiProperty({
-    example: '123e4567-e89b-12d3-a456-426614174000',
+    example: true,
+    description: 'published field',
+    required: false,
+  })
+  @IsBoolean()
+  @IsOptional()
+  published?: boolean;
+
+  @ApiProperty({
+    example: 0,
     description: 'videoStartTimestamp field',
     required: false,
   })
diff --git a/backend/src/lessons/dto/lesson-response.dto.ts b/backend/src/lessons/dto/lesson-response.dto.ts
index 07f422e..2cf81da 100644
--- a/backend/src/lessons/dto/lesson-response.dto.ts
+++ b/backend/src/lessons/dto/lesson-response.dto.ts
@@ -20,13 +20,15 @@ export class LessonResponseDto {
   title: string;
   @ApiProperty({ example: 'example', description: 'content field' })
   content: string;
+  @ApiProperty({ example: true, description: 'published field' })
+  published: boolean;
   @ApiProperty({
-    example: '123e4567-e89b-12d3-a456-426614174000',
+    example: 'https://example.com/video.mp4',
     description: 'videoUrl field',
   })
   videoUrl: string | null;
   @ApiProperty({
-    example: '123e4567-e89b-12d3-a456-426614174000',
+    example: 0,
     description: 'videoStartTimestamp field',
   })
   videoStartTimestamp: number | null;
@@ -61,6 +63,7 @@ export class LessonResponseDto {
     this.id = lesson.id;
     this.title = lesson.title;
     this.content = lesson.content;
+    this.published = lesson.published !== undefined ? lesson.published : true;
     this.videoUrl = lesson.videoUrl || null;
     this.videoStartTimestamp = lesson.videoStartTimestamp || null;
     this.order = lesson.order;
diff --git a/backend/src/lessons/dto/update-lesson.dto.ts b/backend/src/lessons/dto/update-lesson.dto.ts
index 63a938a..9f63c8a 100644
--- a/backend/src/lessons/dto/update-lesson.dto.ts
+++ b/backend/src/lessons/dto/update-lesson.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateLessonDto } from './create-lesson.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateLessonDto extends PartialType(CreateLessonDto) {}
diff --git a/backend/src/lessons/entities/lesson.entity.ts b/backend/src/lessons/entities/lesson.entity.ts
index 286357b..a6d3f5a 100644
--- a/backend/src/lessons/entities/lesson.entity.ts
+++ b/backend/src/lessons/entities/lesson.entity.ts
@@ -21,6 +21,9 @@ export class Lesson {
   @Column('text')
   content: string;
 
+  @Column({ default: true })
+  published: boolean;
+
   @Column({ type: 'varchar', nullable: true })
   videoUrl: string; // External video URL
 
diff --git a/backend/src/lessons/lessons.controller.ts b/backend/src/lessons/lessons.controller.ts
index e0451e1..d18df70 100644
--- a/backend/src/lessons/lessons.controller.ts
+++ b/backend/src/lessons/lessons.controller.ts
@@ -95,6 +95,7 @@ export class LessonsController {
       courseId,
       page,
       limit,
+      true,
     );
     return {
       ...result,
diff --git a/backend/src/lessons/lessons.service.ts b/backend/src/lessons/lessons.service.ts
index 09fa834..2b82a95 100644
--- a/backend/src/lessons/lessons.service.ts
+++ b/backend/src/lessons/lessons.service.ts
@@ -41,12 +41,19 @@ export class LessonsService {
       videoStartTimestamp: createLessonDto.videoStartTimestamp,
       order: createLessonDto.order ?? 0,
       courseId: createLessonDto.courseId,
+      published:
+        createLessonDto.published !== undefined
+          ? createLessonDto.published
+          : true,
     });
 
     return this.lessonRepository.save(lesson);
   }
 
-  async findAllByCourse(courseId: string): Promise<Lesson[]> {
+  async findAllByCourse(
+    courseId: string,
+    publishedOnly: boolean = false,
+  ): Promise<Lesson[]> {
     // Verify course exists
     const course = await this.courseRepository.findOne({
       where: { id: courseId },
@@ -56,8 +63,13 @@ export class LessonsService {
       throw new NotFoundException(`Course with ID ${courseId} not found`);
     }
 
+    const whereCondition: any = { courseId };
+    if (publishedOnly) {
+      whereCondition.published = true;
+    }
+
     return this.lessonRepository.find({
-      where: { courseId },
+      where: whereCondition,
       order: { order: 'ASC', createdAt: 'ASC' },
     });
   }
@@ -79,6 +91,7 @@ export class LessonsService {
     courseId: string,
     page: number,
     limit: number,
+    publishedOnly: boolean = false,
   ): Promise<
     PaginatedResult<Lesson & { hasQuiz: boolean; quizId: string | null }>
   > {
@@ -90,11 +103,16 @@ export class LessonsService {
       throw new NotFoundException(`Course with ID ${courseId} not found`);
     }
 
+    const whereCondition: any = { courseId };
+    if (publishedOnly) {
+      whereCondition.published = true;
+    }
+
     const result = await this.paginationService.paginate(
       this.lessonRepository,
       { page, limit },
       {
-        where: { courseId },
+        where: whereCondition,
         order: { order: 'ASC', createdAt: 'ASC' },
       },
     );
@@ -176,6 +194,9 @@ export class LessonsService {
     if (updateLessonDto.order !== undefined) {
       lesson.order = updateLessonDto.order;
     }
+    if (updateLessonDto.published !== undefined) {
+      lesson.published = updateLessonDto.published;
+    }
 
     return this.lessonRepository.save(lesson);
   }
@@ -207,4 +228,17 @@ export class LessonsService {
       ),
     );
   }
+
+  async setPublished(id: string, published: boolean): Promise<Lesson> {
+    const lesson = await this.lessonRepository.findOne({
+      where: { id },
+    });
+
+    if (!lesson) {
+      throw new NotFoundException(`Lesson with ID ${id} not found`);
+    }
+
+    lesson.published = published;
+    return this.lessonRepository.save(lesson);
+  }
 }
diff --git a/backend/src/progress/dto/create-progress.dto.ts b/backend/src/progress/dto/create-progress.dto.ts
index 57c9fca..53914d4 100644
--- a/backend/src/progress/dto/create-progress.dto.ts
+++ b/backend/src/progress/dto/create-progress.dto.ts
@@ -1,2 +1 @@
-import { ApiProperty } from '@nestjs/swagger';
 export class CreateProgressDto {}
diff --git a/backend/src/progress/dto/update-progress.dto.ts b/backend/src/progress/dto/update-progress.dto.ts
index d5587cf..88ee423 100644
--- a/backend/src/progress/dto/update-progress.dto.ts
+++ b/backend/src/progress/dto/update-progress.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateProgressDto } from './create-progress.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateProgressDto extends PartialType(CreateProgressDto) {}
diff --git a/backend/src/quizzes/dto/update-quiz.dto.ts b/backend/src/quizzes/dto/update-quiz.dto.ts
index 3dc47ae..494f3af 100644
--- a/backend/src/quizzes/dto/update-quiz.dto.ts
+++ b/backend/src/quizzes/dto/update-quiz.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateQuizDto } from './create-quiz.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateQuizDto extends PartialType(CreateQuizDto) {}
diff --git a/backend/src/rewards/dto/create-reward.dto.ts b/backend/src/rewards/dto/create-reward.dto.ts
index 6b82f20..69a443b 100644
--- a/backend/src/rewards/dto/create-reward.dto.ts
+++ b/backend/src/rewards/dto/create-reward.dto.ts
@@ -1,2 +1 @@
-import { ApiProperty } from '@nestjs/swagger';
 export class CreateRewardDto {}
diff --git a/backend/src/rewards/dto/update-reward.dto.ts b/backend/src/rewards/dto/update-reward.dto.ts
index 238590c..263419b 100644
--- a/backend/src/rewards/dto/update-reward.dto.ts
+++ b/backend/src/rewards/dto/update-reward.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateRewardDto } from './create-reward.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateRewardDto extends PartialType(CreateRewardDto) {}
diff --git a/backend/src/rewards/rewards.controller.ts b/backend/src/rewards/rewards.controller.ts
index 7d33205..9cda998 100644
--- a/backend/src/rewards/rewards.controller.ts
+++ b/backend/src/rewards/rewards.controller.ts
@@ -26,9 +26,6 @@ export class RewardsController {
   @Get('my')
   @UseGuards(JwtAuthGuard)
   @ApiBearerAuth('access-token')
-  @ApiOperation({ summary: 'Get my rewards' })
-  @ApiResponse({ status: 200, description: 'Rewards retrieved successfully' })
-  @ApiResponse({ status: 401, description: 'Unauthorized' })
   @ApiOperation({
     summary: 'Get my rewards',
     description:
diff --git a/backend/src/rewards/rewards.service.ts b/backend/src/rewards/rewards.service.ts
index 1c04832..e5af966 100644
--- a/backend/src/rewards/rewards.service.ts
+++ b/backend/src/rewards/rewards.service.ts
@@ -10,6 +10,11 @@ import {
 } from './entities/reward-history.entity';
 import { UserBadge } from './entities/user-badge.entity';
 
+import { NotificationsService } from '../notifications/notifications.service';
+import { WebhooksService } from '../webhooks/webhooks.service';
+import { WebhookEvent } from '../webhooks/dto/create-webhook.dto';
+import { NotificationType } from '../notifications/entities/notification.entity';
+
 export const XP_LESSON_COMPLETE = 10;
 export const XP_QUIZ_PASS = 25;
 export const XP_COURSE_COMPLETE = 100;
@@ -34,6 +39,8 @@ export class RewardsService {
     private readonly userRepository: Repository<User>,
     @InjectRepository(RewardHistory)
     private readonly rewardHistoryRepository: Repository<RewardHistory>,
+    private readonly notificationsService: NotificationsService,
+    private readonly webhooksService: WebhooksService,
   ) {}
 
   async awardXP(
@@ -103,10 +110,29 @@ export class RewardsService {
         continue;
       }
 
-      await this.userBadgeRepository.save(
-        this.userBadgeRepository.create({ userId, badgeId: badge.id }),
-      );
-      newlyEarned.push(badge);
+      try {
+        await this.userBadgeRepository.save(
+          this.userBadgeRepository.create({ userId, badgeId: badge.id }),
+        );
+        newlyEarned.push(badge);
+
+        await this.notificationsService.createNotification(
+          userId,
+          NotificationType.BADGE_EARNED,
+          `You earned a new badge: ${badge.name}.`,
+          '/rewards',
+        );
+
+        // Dispatch webhook event
+        await this.webhooksService.dispatchEvent(WebhookEvent.BADGE_EARNED, {
+          userId,
+          badgeId: badge.id,
+          badgeName: badge.name,
+          awardedAt: new Date(),
+        });
+      } catch {
+        // Unique constraint race: ignore
+      }
     }
 
     return newlyEarned;
diff --git a/backend/src/users/dto/create-user.dto.ts b/backend/src/users/dto/create-user.dto.ts
index 0875b14..0311be1 100644
--- a/backend/src/users/dto/create-user.dto.ts
+++ b/backend/src/users/dto/create-user.dto.ts
@@ -1,2 +1 @@
-import { ApiProperty } from '@nestjs/swagger';
 export class CreateUserDto {}
diff --git a/backend/src/users/dto/update-user.dto.ts b/backend/src/users/dto/update-user.dto.ts
index 270a0e4..dfd37fb 100644
--- a/backend/src/users/dto/update-user.dto.ts
+++ b/backend/src/users/dto/update-user.dto.ts
@@ -1,5 +1,4 @@
 import { PartialType } from '@nestjs/mapped-types';
 import { CreateUserDto } from './create-user.dto';
-import { ApiProperty } from '@nestjs/swagger';
 
 export class UpdateUserDto extends PartialType(CreateUserDto) {}
diff --git a/backend/src/users/streak.service.ts b/backend/src/users/streak.service.ts
index 8b2223f..df06c74 100644
--- a/backend/src/users/streak.service.ts
+++ b/backend/src/users/streak.service.ts
@@ -1,6 +1,6 @@
 import { Injectable } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
-import { Repository, LessThan } from 'typeorm';
+import { Repository } from 'typeorm';
 import { Cron, CronExpression } from '@nestjs/schedule';
 import { User } from './entities/user.entity';
 import { RewardsService } from '../rewards/rewards.service';
diff --git a/backend/src/users/users.controller.spec.ts b/backend/src/users/users.controller.spec.ts
index 9533179..4160787 100644
--- a/backend/src/users/users.controller.spec.ts
+++ b/backend/src/users/users.controller.spec.ts
@@ -116,4 +116,49 @@ describe('UsersController', () => {
       expect(result).toBeUndefined();
     });
   });
+
+  describe('POST /me/avatar', () => {
+    const validFile = {
+      size: 1024,
+      mimetype: 'image/png',
+      originalname: 'avatar.png',
+      buffer: Buffer.from('fake-image'),
+    };
+
+    it('returns avatarUrl on successful upload', async () => {
+      userService.uploadAvatar = jest.fn().mockResolvedValue({
+        avatarUrl: '/uploads/avatars/uuid.png',
+      });
+
+      const result = await controller.uploadMyAvatar(mockRequest, validFile as any);
+
+      expect(userService.uploadAvatar).toHaveBeenCalledWith(
+        'user-1',
+        validFile,
+      );
+      expect(result).toEqual({ avatarUrl: '/uploads/avatars/uuid.png' });
+    });
+
+    it('propagates BadRequestException from service for non-image files', async () => {
+      userService.uploadAvatar = jest.fn().mockRejectedValue(
+        new BadRequestException('Only image files are allowed'),
+      );
+      const nonImageFile = { ...validFile, mimetype: 'application/pdf' };
+
+      await expect(
+        controller.uploadMyAvatar(mockRequest, nonImageFile as any),
+      ).rejects.toThrow(BadRequestException);
+    });
+
+    it('propagates BadRequestException from service for oversized files', async () => {
+      userService.uploadAvatar = jest.fn().mockRejectedValue(
+        new BadRequestException('Avatar file size must be <= 2MB'),
+      );
+      const largeFile = { ...validFile, size: 999 * 1024 * 1024 };
+
+      await expect(
+        controller.uploadMyAvatar(mockRequest, largeFile as any),
+      ).rejects.toThrow(BadRequestException);
+    });
+  });
 });
diff --git a/backend/src/users/users.controller.ts b/backend/src/users/users.controller.ts
index d86362b..3b04e45 100644
--- a/backend/src/users/users.controller.ts
+++ b/backend/src/users/users.controller.ts
@@ -85,7 +85,6 @@ export class UsersController {
   ) {
     return this.userService.uploadAvatar(req.user.id as string, file);
   }
-
   @Post('me/wallet/challenge')
   @HttpCode(HttpStatus.OK)
   @ApiOperation({ summary: 'Generate wallet verification challenge' })
diff --git a/backend/src/webhooks/dto/create-webhook.dto.ts b/backend/src/webhooks/dto/create-webhook.dto.ts
index d1f8515..1410ecb 100644
--- a/backend/src/webhooks/dto/create-webhook.dto.ts
+++ b/backend/src/webhooks/dto/create-webhook.dto.ts
@@ -1,4 +1,4 @@
-import { IsUrl, IsString, IsArray, IsEnum, IsNotEmpty } from 'class-validator';
+import { IsUrl, IsArray, IsEnum, IsNotEmpty } from 'class-validator';
 import { ApiProperty } from '@nestjs/swagger';
 
 export enum WebhookEvent {
diff --git a/backend/tsconfig.json b/backend/tsconfig.json
index 118f151..73d5fa0 100644
--- a/backend/tsconfig.json
+++ b/backend/tsconfig.json
@@ -19,5 +19,5 @@
     "strictBindCallApply": false,
     "noFallthroughCasesInSwitch": false
   },
-  "exclude": ["node_modules", "scripts"]
+  "exclude": ["node_modules", "scripts", "dist"]
 }
diff --git a/frontend/app/admin/page.tsx b/frontend/app/admin/page.tsx
index e2decaa..bd7471c 100644
--- a/frontend/app/admin/page.tsx
+++ b/frontend/app/admin/page.tsx
@@ -15,7 +15,7 @@ interface Course {
 }
 
 export default function AdminPage() {
-  const { data, isLoading, isError, refetch } = useQuery({
+  const { data, isLoading, isError, refetch } = useQuery<Course[]>({
     queryKey: ["admin-courses-list"],
     queryFn: async () => {
       const res = await api.get<{ data?: Course[] } | Course[]>("/courses?limit=100")
diff --git a/frontend/app/layout.tsx b/frontend/app/layout.tsx
index bb29da9..a9782e4 100644
--- a/frontend/app/layout.tsx
+++ b/frontend/app/layout.tsx
@@ -4,7 +4,6 @@ import { Toaster } from "sonner";
 import "./globals.css";
 import { AuthProvider } from "@/contexts/auth-context";
 import { LearningProvider } from "@/contexts/learning-context";
-import { Providers } from "@/components/providers";
 import { UserProvider } from "@/contexts/user-context";
 import { ReactQueryProvider } from "@/lib/query-client";
 
diff --git a/frontend/app/profile/page.tsx b/frontend/app/profile/page.tsx
index 2660f6e..e8058e5 100644
--- a/frontend/app/profile/page.tsx
+++ b/frontend/app/profile/page.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import Image from "next/image";
+
 import { Header } from "@/components/header";
 import { Card, CardContent } from "@/components/ui/card";
 import { Button } from "@/components/ui/button";
@@ -11,16 +11,12 @@ import { useEffect } from "react";
 import { AvatarUpload } from "@/components/profile/avatar-upload";
 import { StatsSummary } from "@/components/profile/stats-summary";
 import { ProfileTabs } from "@/components/profile/profile-tabs";
-import {
   ArrowLeft,
   Mail,
   Shield,
   Settings,
-  User as UserIcon,
   Loader2,
-  ExternalLink,
   Calendar,
-  MapPin,
   Sparkles
 } from "lucide-react";
 import Link from "next/link";
@@ -142,7 +138,6 @@ export default function ProfilePage() {
               streak={stats.streakDays}
               badgesCount={stats.badgesCount}
               certificatesCount={stats.certificatesCount}
-              completedCourses={userStats?.completedCourseCount ?? 0}
             />
 
             <div className="relative group">
diff --git a/frontend/app/settings/page.tsx b/frontend/app/settings/page.tsx
index fbc27d1..fe47801 100644
--- a/frontend/app/settings/page.tsx
+++ b/frontend/app/settings/page.tsx
@@ -3,7 +3,7 @@
 import { useEffect, useMemo, useState, useCallback } from "react";
 import Link from "next/link";
 import { useRouter } from "next/navigation";
-import { ArrowLeft, Bell, LogOut, Save, Settings, User, CheckCircle, Sparkles, Shield, Mail } from "lucide-react";
+import { ArrowLeft, Bell, LogOut, Save, Settings, User, CheckCircle, Sparkles } from "lucide-react";
 import { toast } from "sonner";
 import { Header } from "@/components/header";
 import { Button } from "@/components/ui/button";
diff --git a/frontend/app/verify-certificate/page.tsx b/frontend/app/verify-certificate/page.tsx
index 36d083e..8e45452 100644
--- a/frontend/app/verify-certificate/page.tsx
+++ b/frontend/app/verify-certificate/page.tsx
@@ -23,7 +23,7 @@ function VerifyCertificateContent() {
   const [inputValue, setInputValue] = useState(initialHash);
   const [activeHash, setActiveHash] = useState(initialHash);
   
-  const { data: result, isLoading: loading, isError, refetch } = useCertificateVerification(activeHash);
+  const { data: result, isLoading: loading } = useCertificateVerification(activeHash);
 
   const handleVerify = (e?: React.FormEvent) => {
     if (e) e.preventDefault();
diff --git a/frontend/components/certificates/certificate-card.tsx b/frontend/components/certificates/certificate-card.tsx
index 0b1d437..1c78c6f 100644
--- a/frontend/components/certificates/certificate-card.tsx
+++ b/frontend/components/certificates/certificate-card.tsx
@@ -6,7 +6,6 @@ import {
   Download, 
   Share2, 
   Check, 
-  ExternalLink,
   Loader2,
   Calendar,
   Award
@@ -15,7 +14,7 @@ import { Button } from "@/components/ui/button";
 import { Card, CardContent } from "@/components/ui/card";
 import { toast } from "sonner";
 import { Certificate } from "@/hooks/use-certificates";
-import { api } from "@/lib/api";
+
 
 interface CertificateCardProps {
   certificate: Certificate;
diff --git a/frontend/components/profile/my-certificates-content.tsx b/frontend/components/profile/my-certificates-content.tsx
index 325dea6..e7ad6a1 100644
--- a/frontend/components/profile/my-certificates-content.tsx
+++ b/frontend/components/profile/my-certificates-content.tsx
@@ -1,8 +1,8 @@
 "use client";
 
-import { AlertTriangle, Loader2, Award } from "lucide-react";
+import { AlertTriangle, Award } from "lucide-react";
 import { CertificateCard } from "@/components/certificates/certificate-card";
-import { useCertificates } from "@/hooks/use-certificates";
+import { useCertificates, Certificate } from "@/hooks/use-certificates";
 import { Button } from "@/components/ui/button";
 import Link from "next/link";
 
@@ -57,7 +57,7 @@ export function MyCertificatesContent() {
 
   return (
     <div className="flex flex-col gap-4">
-      {certificates.map((cert) => (
+      {certificates.map((cert: Certificate) => (
         <CertificateCard key={cert.id} certificate={cert} />
       ))}
     </div>
diff --git a/frontend/components/profile/stats-summary.tsx b/frontend/components/profile/stats-summary.tsx
index 2b111be..2508858 100644
--- a/frontend/components/profile/stats-summary.tsx
+++ b/frontend/components/profile/stats-summary.tsx
@@ -1,14 +1,13 @@
 "use client";
 
 import { Card, CardContent } from "@/components/ui/card";
-import { Award, Flame, GraduationCap, Trophy, Zap, Sparkles } from "lucide-react";
+import { Award, Flame, GraduationCap, Zap } from "lucide-react";
 
 interface StatsSummaryProps {
   xp: number;
   streak: number;
   badgesCount: number;
   certificatesCount: number;
-  completedCourses: number;
 }
 
 export function StatsSummary({
@@ -16,7 +15,6 @@ export function StatsSummary({
   streak,
   badgesCount,
   certificatesCount,
-  completedCourses,
 }: StatsSummaryProps) {
   const cards = [
     {
diff --git a/frontend/contexts/learning-context.tsx b/frontend/contexts/learning-context.tsx
index 98895dd..76885b2 100644
--- a/frontend/contexts/learning-context.tsx
+++ b/frontend/contexts/learning-context.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import React, { createContext, useContext, useState, useEffect } from "react";
+import React, { createContext, useContext, useState, useEffect, useCallback } from "react";
 import { toast } from "sonner";
 import { api } from "@/lib/api";
 import { PLACEHOLDER_VIDEO_URL } from "@/lib/constants";
@@ -61,6 +61,7 @@ interface LearningContextType {
   quizResults: Record<string, QuizResult>;
   isSubmittingQuiz: boolean;
   isCompletingLesson: boolean;
+  enrollInCourse: (courseId: string) => Promise<void>;
   markLessonComplete: (courseId: string, lessonId: string) => Promise<boolean>;
   submitQuiz: (
     quizId: string,
@@ -358,6 +359,41 @@ export function LearningProvider({ children }: { children: React.ReactNode }) {
   const [isSubmittingQuiz, setIsSubmittingQuiz] = useState(false);
   const [isCompletingLesson, setIsCompletingLesson] = useState(false);
 
+  const fetchCourses = useCallback(async () => {
+    const token = typeof window !== "undefined" ? localStorage.getItem("auth_token") : null;
+    if (!token) return;
+    try {
+      interface RawCourseResponse {
+        id: string;
+        title: string;
+        description: string;
+        progressPercent?: number;
+        isEnrolled?: boolean;
+      }
+      const data = await api.get<RawCourseResponse[] | { data: RawCourseResponse[] }>("/courses");
+      const list = Array.isArray(data) ? data : (data as { data: RawCourseResponse[] }).data ?? [];
+      setCourses(
+        list.map((c) => ({
+          id: c.id,
+          title: c.title,
+          description: c.description,
+          difficulty: "Beginner" as const,
+          rating: 0,
+          duration: 0,
+          lessons: [],
+          progress: c.progressPercent ?? 0,
+          enrolled: c.isEnrolled ?? false,
+        }))
+      );
+    } catch {
+      // silently fail — courses stay as is (mock or cached)
+    }
+  }, []);
+
+  useEffect(() => {
+    void fetchCourses();
+  }, [fetchCourses]);
+
   // Save to localStorage whenever courses or quizResults change
   useEffect(() => {
     if (typeof window !== "undefined") {
@@ -374,6 +410,16 @@ export function LearningProvider({ children }: { children: React.ReactNode }) {
     }
   }, [quizResults]);
 
+  const enrollInCourse = async (courseId: string) => {
+    try {
+      await api.post(`/courses/${courseId}/enroll`, {});
+      await fetchCourses();
+      toast.success("Enrolled successfully!");
+    } catch {
+      toast.error("Failed to enroll in course.");
+    }
+  };
+
   const markLessonComplete = async (
     courseId: string,
     lessonId: string,
@@ -398,17 +444,17 @@ export function LearningProvider({ children }: { children: React.ReactNode }) {
         progressRows.map((row) => [row.lessonId, row.completed]),
       );
 
-      setCourses((prev) =>
-        prev.map((course) => {
+      setCourses((prev: Course[]) =>
+        prev.map((course: Course) => {
           if (course.id !== courseId) {
             return course;
           }
-          const updatedLessons = course.lessons.map((lesson) => ({
+          const updatedLessons = course.lessons.map((lesson: Lesson) => ({
             ...lesson,
             completed: completedByLessonId.get(lesson.id) ?? lesson.completed,
           }));
           const completedCount = updatedLessons.filter(
-            (l) => l.completed,
+            (l: Lesson) => l.completed,
           ).length;
           const progress = updatedLessons.length
             ? (completedCount / updatedLessons.length) * 100
@@ -469,7 +515,7 @@ export function LearningProvider({ children }: { children: React.ReactNode }) {
         submittedAt: submission.submittedAt,
       };
 
-      setQuizResults((prev) => ({ ...prev, [quizId]: result }));
+      setQuizResults((prev: Record<string, QuizResult>) => ({ ...prev, [quizId]: result }));
       return result;
     } catch (error) {
       const status = (error as { status?: number }).status;
@@ -487,7 +533,7 @@ export function LearningProvider({ children }: { children: React.ReactNode }) {
   };
 
   const getCourseProgress = (courseId: string): number => {
-    const course = courses.find((c) => c.id === courseId);
+    const course = courses.find((c: Course) => c.id === courseId);
     return course?.progress || 0;
   };
 
diff --git a/frontend/contexts/user-context.tsx b/frontend/contexts/user-context.tsx
index d495235..38b244f 100644
--- a/frontend/contexts/user-context.tsx
+++ b/frontend/contexts/user-context.tsx
@@ -178,7 +178,7 @@ export function UserProvider({ children }: { children: React.ReactNode }) {
     } catch (err) {
       console.error("Failed to load user data:", err);
       // Ensure we have at least a fallback user if token exists
-      setUser((prev) => prev ?? getLocalFallbackUser());
+      setUser((prev: UserProfile | null) => prev ?? getLocalFallbackUser());
     }
   }, [getLocalFallbackUser, mapUser]);
 
@@ -205,7 +205,7 @@ export function UserProvider({ children }: { children: React.ReactNode }) {
         updates.email === undefined &&
         updates.bio === undefined
       ) {
-        setUser((prev) => (prev ? { ...prev, avatar: updates.avatar } : prev));
+        setUser((prev: UserProfile | null) => (prev ? { ...prev, avatar: updates.avatar } : prev));
         return;
       }
 
@@ -253,7 +253,7 @@ export function UserProvider({ children }: { children: React.ReactNode }) {
         ...defaultNotificationPreferences,
         ...(updated.notificationPreferences ?? updatedPrefs),
       });
-      setUser((prev) => {
+      setUser((prev: UserProfile | null) => {
         if (!prev) return prev;
         return mapUser({
           ...updated,
diff --git a/frontend/e2e/learning.spec.ts b/frontend/e2e/learning.spec.ts
index 5a4e1cb..9ba4e5b 100644
--- a/frontend/e2e/learning.spec.ts
+++ b/frontend/e2e/learning.spec.ts
@@ -4,7 +4,7 @@ test.describe.serial('Learning Flow', () => {
   const testEmail = `learner_${Date.now()}@example.com`;
   const testPassword = 'Password123!';
 
-  test.beforeAll(async ({ request }) => {
+  test.beforeAll(async () => {
     // Optionally create a user here via API if needed, 
     // but the test can also just register via UI
   });