Juan Montero

About

Senior Software Engineer and SaaS Architect with 15+ years of experience building production-grade platforms end-to-end (multi-tenant SaaS, Flutter mobile, React/Next.js, Node.js, PostgreSQL/Supabase) across FinTech, healthcare, hospitality, aviation, and AI automation. Built 23+ live products as a solo full-stack developer, integrating AI/LLM workflows and messaging automation (WhatsApp Cloud API), and delivering Stripe-based billing and multi-currency SaaS systems.

Experience

• Senior Software Engineer & SaaS Architect (Freelance) · Freelance (Upwork / People Per Hour)2009

  Full ownership of architecture, backend, frontend, and mobile layers across 23+ production platforms serving clients in FinTech, healthcare, hospitality, aviation, recruitment, and AI automation. • Architected and shipped 9+ multi-tenant SaaS platforms with org-level data isolation, RBAC, and subscription billing. • Built scalable REST APIs in Node.js/TypeScript with PostgreSQL and Supabase, including RLS-enforced tenant separation. • Developed 10+ Flutter mobile apps targeting both iOS and Google Play, including offline-capable and location-aware apps. • Integrated AI/LLM providers (OpenAI, Claude, Gemini) into workflow automation and chatbot products. • Implemented WhatsApp Business Cloud API end-to-end including webhook ingestion, session management, and chatbot flows. • Delivered Stripe Connect payment flows and tiered subscription billing for marketplace and SaaS products. • Deployed and maintained production apps on Railway, Vercel, and Supabase with CI/CD pipelines.

Education

• Florida International UniversityBachelor of Science in Computer Engineering (BSCpE), Bachelor of Science in Computer Engineering (BSCpE)

Similar talent on Pangea

Brijesh S.Senior Flutter Mobile App Developer | 6+ Years | Performance & Cross-Platform (iOS/Android)Ahmedabad, GujaratGabriel A.Experienced Full Stack Engineer and Flutter ExpertNew York, NYHatim E.Full-Stack Engineer | Next.js · Supabase · AI Integrations · iOS — 6+ years shipping production MVPsSan Pablo City, LagunaTTravis B.Senior Software Engineer | Full-Stack & Cloud | AI/ML-Enabled PlatformsPhoenix, AZ