OpenCCB is a high-performance, microservices-based Learning Management System (LMS) and Content Management System (CMS) built with Rust (Edition 2024) and Next.js. The name stands for Open Comprehensive Course Backbone, representing the solid foundation for modern educational platforms.

Architecture

CMS Service (Port 3001): Course management, content creation, grading policies, and administrative configurations.
LMS Service (Port 3002): Student experience, course consumption, enrollment, and grade tracking.
Shared Library: Core models, authentication logic, and cross-service data contracts.
Database: PostgreSQL with separate databases for CMS and LMS.
Studio (Frontend): Next.js application for instructors with block-based Activity Builder.
Experience (Frontend): Next.js student portal with interactive lesson player and progress dashboard.
Asset Storage: Persistent local storage for native video/audio uploads.

Getting Started

Prerequisites

Docker & Docker Compose
Rust (Edition 2024)
Node.js (v18+)

Running with Docker

docker compose up -d --build

Access Points

Studio (Instructors): http://localhost:3000
Experience (Students): http://localhost:3003
CMS API: http://localhost:3001
LMS API: http://localhost:3002

Core Features

🎨 Content Creation & Management

Block-Based Activity Builder: Create rich lessons using text, media, and interactive assessment blocks
Advanced Assessment Types:
- Multiple Choice & True/False
- Fill-in-the-Blanks
- Matching Pairs
- Ordering/Sequencing
- Short Answer (with configurable correct answers)
Native File Uploads: Drag-and-drop video/audio uploads with persistent storage
Playback Constraints: Limit media views per student
Dynamic Content Reordering: Organize blocks with move up/down controls
Course Settings: Configure passing percentages and grading criteria

📊 Advanced Grading System

Holistic Grading Policy:
- Create weighted grading categories (e.g., Homework 30%, Exams 70%)
- Drop lowest N scores per category
- Automatic weighted grade calculation
Configurable Assessment Policies:
- Set maximum attempts per lesson (1-10 or unlimited)
- Enable/disable instant corrections and retries
- Atomic attempt tracking with enforcement
Dynamic Passing Thresholds:
- Instructors set custom passing percentages (0-100%)
- 5-tier performance visualization for students:
  - Reprobado (Red): 0% to P-1%
  - Rendimiento Bajo (Orange): P% to P+9%
  - Rendimiento Medio (Yellow): P+10% to P+15%
  - Buen Rendimiento (Green): P+16% to 90%
  - Excelente (Blue): 91%+

📈 Analytics & Insights

Instructor Analytics Dashboard:
- Total enrollments per course
- Overall average score across all assessments
- Per-lesson performance breakdown
- Automatic detection of "struggling lessons" (avg score < 70%)
- Visual performance charts
Student Progress Dashboard:
- Real-time weighted grade calculation
- Category-by-category breakdown
- Interactive performance bar with tier visualization
- Lesson completion tracking

🔐 Authentication & Security

JWT-Based Authentication: Secure token-based auth across all services
Role-Based Access Control (RBAC):
- Administrators: Full platform access, global analytics, all course management
- Instructors: Course creation, analytics for assigned courses only
- Students: Course enrollment, lesson consumption, progress tracking
Service-to-Service Authorization: Secure internal API calls with token validation
Audit Logging: All CMS mutations recorded for compliance and debugging

🚀 Service Integration

Automatic Sync: One-click publish from CMS to LMS
Cross-Service Data Flow: Courses, modules, lessons, and grading policies synchronized
Real-Time Updates: Student progress immediately reflected in analytics

API Documentation

CMS Service (`:3001`)

Authentication

# Register (Instructor/Admin)
curl -X POST http://localhost:3001/auth/register \
  -H "Content-Type: application/json" \
  -d '{"email": "instructor@example.com", "password": "secure123", "full_name": "John Doe", "role": "instructor"}'

# Login
curl -X POST http://localhost:3001/auth/login \
  -H "Content-Type: application/json" \
  -d '{"email": "instructor@example.com", "password": "secure123"}'

Course Management

# Create Course
curl -X POST http://localhost:3001/courses \
  -H "Content-Type: application/json" \
  -d '{"title": "Advanced Rust 2024"}'

# Update Course Settings
curl -X PUT http://localhost:3001/courses/{id} \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -d '{"passing_percentage": 75}'

# Publish Course to LMS
curl -X POST http://localhost:3001/courses/{id}/publish \
  -H "Authorization: Bearer YOUR_TOKEN"

# Get Course Analytics (RBAC enforced)
curl http://localhost:3001/courses/{id}/analytics \
  -H "Authorization: Bearer YOUR_TOKEN"

LMS Service (`:3002`)

Student Operations

# Register Student
curl -X POST http://localhost:3002/auth/register \
  -H "Content-Type: application/json" \
  -d '{"email": "student@example.com", "password": "secure123", "full_name": "Jane Smith"}'

# Get Course Catalog
curl http://localhost:3002/catalog

# Enroll in Course
curl -X POST http://localhost:3002/enroll \
  -H "Content-Type: application/json" \
  -d '{"user_id": "USER_UUID", "course_id": "COURSE_UUID"}'

# Submit Lesson Score
curl -X POST http://localhost:3002/grades \
  -H "Content-Type: application/json" \
  -d '{"user_id": "USER_UUID", "lesson_id": "LESSON_UUID", "score": 0.85}'

# Get Student Grades
curl http://localhost:3002/users/{user_id}/courses/{course_id}/grades

Technology Stack

Backend

Rust 2024: High-performance, memory-safe backend services
Axum 0.8: Modern async web framework
SQLx: Compile-time verified SQL queries
PostgreSQL: Robust relational database
JWT: Secure authentication tokens

Frontend

Next.js 14: React framework with App Router
TypeScript: Type-safe frontend development
Tailwind CSS: Utility-first styling
Lucide React: Modern icon library

DevOps

Docker: Containerized deployment
Docker Compose: Multi-service orchestration

Project Structure

openccb/
├── services/
│   ├── cms-service/          # Course management backend
│   │   ├── src/
│   │   │   ├── handlers.rs   # API handlers
│   │   │   └── main.rs       # Service entry point
│   │   └── migrations/       # Database migrations
│   └── lms-service/          # Learning management backend
│       ├── src/
│       │   ├── handlers.rs   # API handlers
│       │   └── main.rs       # Service entry point
│       └── migrations/       # Database migrations
├── shared/
│   └── common/               # Shared models and auth
│       └── src/
│           ├── models.rs     # Data models
│           └── auth.rs       # JWT utilities
├── web/
│   ├── studio/               # Instructor frontend
│   │   └── src/
│   │       ├── app/          # Next.js pages
│   │       ├── components/   # React components
│   │       └── lib/          # API client
│   └── experience/           # Student frontend
│       └── src/
│           ├── app/          # Next.js pages
│           ├── components/   # React components
│           └── lib/          # API client
└── docker-compose.yml        # Service orchestration

Recent Enhancements

December 2024

✅ Holistic Grading System: Weighted categories, drop policies, and automatic calculation
✅ Attempt Tracking: Configurable max attempts and retry policies per lesson
✅ Instructor Analytics: Course-level insights with RBAC enforcement
✅ Dynamic Passing Thresholds: Customizable pass marks with 5-tier performance visualization
✅ Role-Based Access Control: Admin, Instructor, and Student roles with granular permissions
✅ Enhanced Progress Dashboard: Real-time weighted grades and visual performance bars

Contributing

Contributions are welcome! Please ensure all tests pass and follow the existing code style.

License

MIT License - see LICENSE file for details.

Languages

TypeScript 54.3%

Rust 28.8%

HTML 10.3%

PLpgSQL 2.7%

Shell 2.4%

Other 1.4%

README.md

OpenCCB - Open Comprehensive Course Backbone