Senior Backend Engineer | Python · Go · Distributed Systems · Fintech & AI Infrastructure
I build production backend systems where data integrity, failure recovery, and operational reliability are critical.
My work focuses on distributed architectures, financial data pipelines, and AI-powered backend systems designed to remain stable under concurrency, retries, and partial failures.
I specialize in building boring systems that don’t break under load.
• Backend systems supporting 100K+ paid users in revenue-critical environments with strict consistency guarantees
• Reduced infrastructure and API costs by $48K/year by replacing third-party services with in-house PostgreSQL workflows
• Improved query performance by ~90% in financial data pipelines serving 3M monthly users through schema redesign and indexing strategies
• Reduced LLM inference costs by ~30% using semantic caching and request-aware model routing
Distributed workflow engine designed to prevent invalid state transitions in financial systems.
Key design ideas:
• Exactly-once state transitions using idempotency keys
• Transactional outbox pattern to safely publish events from PostgreSQL
• Optimistic locking to prevent concurrent state corruption
Built to survive retries, crashes, and duplicate events in distributed financial workflows.
Large-scale ingestion pipeline for document processing and vector indexing.
Key design ideas:
• Idempotent document ingestion preventing duplicate embeddings
• Dead Letter Queue (DLQ) recovery for rate limits and partial failures
• Deterministic indexing enabling safe retries without data corruption
Designed for predictable cost, high throughput, and zero data loss in production AI systems.
Core stack
Python · Go · PostgreSQL · Kafka · Redis · FastAPI
Architecture patterns
Event-driven systems · Idempotency · Transactional Outbox · Async processing · Failure recovery
Currently exploring
Go for high-throughput backend services and distributed API systems
LinkedIn: https://linkedin.com/in/winsongr
LeetCode: https://leetcode.com/u/winsongr