# ADR-0024: Background Job Scheduler

## Status
Accepted

## Context
The platform needs background job processing for:
- Periodic tasks (cron jobs)
- Asynchronous processing
- Long-running operations
- Retry logic for failed jobs

Options considered:
1. **asynq (Redis-based)** - Simple, feature-rich
2. **cron + custom queue** - Build our own
3. **Kafka consumers** - Use event bus
4. **External service** - AWS SQS, etc.

## Decision
Use **asynq** (Redis-backed) for job scheduling:

1. **Cron jobs**: `github.com/robfig/cron/v3` for periodic tasks
2. **Job queue**: `github.com/hibiken/asynq` for async jobs
3. **Storage**: Redis (shared with cache)
4. **Features**: Retries, backoff, job status tracking

**Rationale:**
- Simple, Redis-backed (no new infrastructure)
- Good Go library support
- Built-in retry and backoff
- Job status tracking
- Easy to integrate
- Can scale horizontally (multiple workers)

## Consequences

### Positive
- Simple (uses existing Redis)
- Feature-rich (retries, backoff)
- Good performance
- Easy to scale
- Job status tracking

### Negative
- Tied to Redis (but we're already using it)
- Requires Redis to be available

### Implementation Notes
- Install: `github.com/hibiken/asynq` and `github.com/robfig/cron/v3`
- Create `pkg/scheduler/scheduler.go` interface
- Implement `internal/infra/scheduler/asynq_scheduler.go`
- Register jobs in `internal/infra/scheduler/job_registry.go`
- Start worker in fx lifecycle
- Configure retry policies (exponential backoff)
- Add job monitoring endpoint