Senior Fintech Backend Engineer

The profile is a highly skilled backend engineer with a strong background in fintech, having been the second engineer at an a16z-backed company. They owned the entire payment stack for two years, managing ACH, wire, check, and card rails, a double-entry PostgreSQL ledger, and robust webhook pipelines. They successfully processed over $150M across 1,800+ customers with zero overdrafts and duplicate payment entries. Key achievements include leading a 10-month migration from Firebase to PostgreSQL without downtime and debugging complex race conditions in payment logic. Additionally, they have experience with AI/LLM applications, having built a SOC 2 audit agent using LangGraph, significantly optimizing tool calls. The candidate is proficient in Python, TypeScript, Go, PostgreSQL, Redis, GCP, FastAPI, Temporal, and LangGraph. They are seeking founding engineer or backend roles, open to remote or on-site positions, and willing to relocate to the UK, Europe, or the US with sponsorship.