• Full ownership of features: take responsibility from concept and architecture to production deployment. • Collaborate with the architect and make independent architectural decisions within your domain. • Work autonomously on complex, distributed systems ensuring scalability, reliability, and performance. • Backend development with Ruby on Rails 8: performance tuning, background jobs (Sidekiq), custom gem development, REST and GraphQL APIs, versioning, rate limiting, secure auth patterns. • Implement microservices and event-driven architectures with inter-service communication patterns. • Database design and optimization for PostgreSQL: query optimization, indexing, partitioning; implement caching with Redis or Memcached. • Frontend development: build performant UIs with JavaScript/TypeScript and frameworks (React, Vue, Angular); optimize bundlers (Webpack, Vite, esbuild); use Hotwire and Tailwind CSS. • Design and maintain CI/CD pipelines; containerize via Docker and Kubernetes; ensure observability (monitoring, logging, Grafana). • Integrate LLMs and agent frameworks (LangChain, CrewAI); implement MCP connectors, vector DBs for RAG, and real-time agent interfaces (WebSockets, SSE, streaming APIs). • Product-focused engineering: implement business logic, optimize for conversion and retention, support A/B testing and feature flags. • Apply security best practices (OWASP), OAuth/JWT flows, encryption at rest and in transit. • Follow TDD with high automated test coverage; perform integration and end-to-end testing; lead code reviews and documentation.