Full-Stack Engineer with 15+ years architecting and scaling multi-tenant SaaS platforms across fintech, insurance, HR-tech, and manufacturing verticals. Deep specialization in TypeScript, Node.js/NestJS, and Nx monorepo architectures, with a consistent record of cutting latency, hardening security, and leading legacy-to-TypeScript migrations at enterprise scale. Extends core full-stack engineering with production-grade AI agent orchestration (LangChain, LangGraph), building automation into the product itself rather than bolting it on as a side feature.

• AI & Agentic Systems: LangGraph (stateful graphs, Postgres checkpointing), LangChain, Claude API, OpenAI API, Gemini API, pgvector / RAG, LLM extraction & structuring pipelines, prompt eval sets
• Languages: TypeScript, JavaScript (ES6+), SQL, NoSQL
• Backend & Architecture: Node.js (NestJS, Hono, Express), modular monoliths, contract-first APIs (Zod, oRPC, OpenAPI/Scalar), REST, GraphQL, event-driven systems (BullMQ, transactional outbox, Kafka, RabbitMQ), Drizzle, TypeORM, Mongoose
• Frontend: Next.js (App Router, RSC), React, TanStack Query/Table, Zustand, Redux, Angular (NgRx, RxJS), Vue/Nuxt (Pinia), Tailwind CSS, Shadcn/UI
• Data & Storage: PostgreSQL (RLS, multi-tenant design, pgvector), Redis, MySQL, MongoDB, DynamoDB
• Platforms & SaaS Integrations: Supabase (managed Postgres, storage, migrations), Better Auth, Stripe (subscriptions, metered billing), Resend, Sentry
• Cloud & DevOps: AWS, Google Cloud, Azure, Docker, Coolify (self-hosted PaaS), CI/CD (GitHub Actions, CircleCI), Nx monorepos, Uptime Kuma
• Data Ingestion: Crawlee, Playwright, tiered scraping (API → RSS → HTTP → headless), PDF extraction
• Testing: Vitest, Jest, Playwright, Cypress, pgTAP

• Building a multi-tenant platform with Next.js, NestJS, and Supabase
• Architecting secure GraphQL APIs and AI-enabled features using LangChain
• Experimenting with monorepos, automation, and developer UX tools
• Running a remote freelance practice and contributing to open source

In my free time, I explore emerging tech (AI agents), build tools, participate in hackathons, and contribute to open-source projects.
I also enjoy reflecting on life, visiting temples, and listening to Thai music.

• BSc in Mathematics and Computation
  University Silverio Blanco Núñez (Cuba)

• Arc.dev: @yosvelquintero
• LinkedIn: yosvelquintero
• StackOverflow: Yosvel Quintero
• Twitter/X: @yosvelquintero