TxFlow — Payment Event Orchestrator

TxFlow is an event-driven payments workflow: a POST /payment request produces one Kafka event, and multiple independent consumer groups process it (fraud, wallet, notifications, audit, analytics) with retries, deduplication, and a DLQ.

Each consumer group owns its own offset, so a failure in one never blocks the other four. Retries are per-consumer, deduplication is a Redis key, and anything still failing is parked in the DLQ for the handler service to inspect or replay.

• Kafka: Redpanda + Redpanda Console UI
• API: FastAPI (Python)
• DB: PostgreSQL
• Cache: Redis (dedup + analytics counters)
• Consumers: Python (confluent-kafka)
• Orchestration: Docker Compose

• Next.js + TypeScript
• shadcn/ui + Tailwind
• Uses Next API routes as a proxy to backend services

From repo root:

cd txflow
cp .env.example .env
docker compose up -d --build

• Dashboard: http://localhost:3000
• Producer: http://localhost:8000/health and http://localhost:8000/analytics
• DLQ handler: http://localhost:8001/dlq
• Redpanda Console: http://localhost:8080

txflow/      # docker-compose + backend services
frontend/    # Next.js dashboard