Senior Python Developer
ItsaCheckmate
Jul 2023 — Present
- Led multi-provider delivery orchestration (Third party delivery providers) with unified abstraction layer for quoting, dispatching, and tracking.
- Built and owned webhook receivers for third-party platforms, including retries, idempotency, and dead-letter handling so events could be processed safely.
- Hardened inbound webhooks with signature verification (HMAC), timestamp checks, and replay protection.
- Worked in a multi-tenant SaaS setup, keeping tenant configuration/data isolated and respecting per-account limits.
- Owned OAuth2/JWT authentication for internal and external APIs, and integrated with third-party token-based auth (refresh flows, secure storage, and rotation patterns).
- Migrated menu system to new architecture with Redis caching, reducing load times from 40 minutes to seconds.
- Designed real-time failover mechanism for automatic rerouting to backup providers, reducing order cancellations.
- Re-engineered Celery background tasks from monolithic to chunk-based architecture with connection pooling.