Senior software engineer with 20 years in C#/.NET and SQL, since 2022 co-founder and tech lead of a cryptocurrency exchange backend (bitrux.io): chain integrations, deposit and withdrawal pipelines, transaction broadcasting and ledger reconciliation. Full-stack when needed, with React and DevExpress on the front end. For the past year I have worked daily with AI coding agents (Claude), which lets me ship a scoped feature in days rather than weeks. Available immediately for fixed-scope contracts or a part-time retainer; I invoice in USDT or USDC.