Senior Ruby on Rails Backend Developer

Senior Ruby on Rails developer with 11+ years of experience across fintech, SaaS, e-commerce, and startups. Specializes in performance optimization (e.g., reducing API response times from 90-120s to 1-2s), external API integrations (Google Maps, Chargebee, WhatsApp, SDB Groep, AFAS) handling complex scenarios like retries and partial failures, and working with legacy codebases through careful refactoring and process implementation (Tech Lead at clevergig). Proficient in Ruby on Rails, PostgreSQL, MySQL, Sidekiq, Redis, AWS, and more, with some experience in Crystal and daily use of Claude Code. Recent roles include FactCTO, Rail Europe, Fitjourney.ai, Kagi, and clevergig. Demonstrates passion for backend and hardware integration through a personal project tracking power outages with a Rails app and ESP32 device. Open to full-time remote or contract opportunities.