composer install
cp .env.example .env
php artisan key:generate
php artisan migrate
php artisan serve

Laravel 12 has this neat feature called deferred jobs that run after the HTTP response is sent. I'm using that to save everything to the database without blocking the API response.

If the job fails, it retries 5 times with exponential backoff. If it still fails, it goes to a dead letter queue so we can investigate later.

Why: Needed fast reads and writes. Redis sorted sets are perfect for leaderboards - O(log N) for most operations.

Trade-off: If Redis crashes, we lose recent data. Mitigated by:

• Redis persistence (AOF + RDB)
• Background jobs sync to database
• Can rebuild Redis from database if needed

The point_transactions table is append-only. Every point award is recorded. This means:

• Full audit trail
• Can rebuild state from events
• Easy to debug issues

The leaderboard_scores table is just a materialized view for performance.

Award endpoint only touches Redis, then dispatches a job. This made response times go from ~15ms to ~2ms.

The job handles:

• Creating transaction record
• Updating materialized view
• Error handling

Using typed DTOs everywhere instead of passing arrays around. Makes the code easier to understand and catches bugs early.

Separated data access from business logic. Makes it easier to:

• Swap Redis for something else later
• Write tests
• Keep code organized

POST /api/leaderboard/award
{
  "user_id": 1,
  "points": 50,
  "source": "purchase"
}

GET /api/leaderboard?limit=100

GET /api/leaderboard/user/1

Response:

{
  "user_id": 1,
  "username": "john",
  "rank": 5,
  "score": 1250.0
}