I am a backend and full-stack software engineer building production-oriented systems with ASP.NET Core, Django, Next.js, and React Native. I work across system design, REST and GraphQL APIs, SQL Server, PostgreSQL, Redis caching, concurrency control, WebSockets, background jobs, JWT security, and automated testing. I helped build a reservation platform serving 5,000+ weekly users, reduced race-condition failures by 82%, contributed to an architecture redesign that cut cost by about 56%, and used K6 at 1,000 concurrent users to uncover EF Core, SQL, and thread-pool bottlenecks.... Lee más