Andrey M.

AI Full Stack Engineer | AI Agents | Firebase | Supabase | Expo | React Native | Next.js Top Rated Plus Freelancer | 18+ Years of Experience | 100% Job Success | Hong Kong Based ☁️🏆✨ Google Cloud Computing Certificate 🤖🔗🧠 Agentic AI Engineer with LangChain and LangGraph Certificate Check the verification links down below in "Certification" section I am a senior Full Stack Engineer and AI engineer with 18+ years of experience building production web and mobile applications, SaaS products, APIs, and AI-powered systems for startups, enterprises, and growing businesses. My expertise spans the full product lifecycle: architecture, backend and mobile development, frontend implementation, cloud deployment, and AI integration. I specialize in high-performance, secure, production-ready applications built for long-term growth. Before freelancing, I worked at BNP Paribas, Citibank, UniCredit, Astek, Prenetics, and EPAM. I am an AI-native engineer. I use Claude Code and Cursor daily to deliver high-quality code fast, without cutting corners on architecture or maintainability. Core Technologies & Expertise • AI Agents and LLM Systems: LangChain, LangGraph, typed state, repair and critic loops, ReAct, Plan-Execute, MCP tool dispatch, LangSmith tracing, RAG knowledge bases, SSE streaming, tool-calling agents, multi-provider LLM routing, Claude, Gemini, OpenAI • Frontend and Mobile: React, Next.js, React Native, Expo, TypeScript, TanStack Query, Zustand • Firebase: Auth, Firestore, Cloud Storage, Cloud Functions v2, Cloud Tasks, App Check, security rules, rate limiting • Supabase: Postgres, Row Level Security, Edge Functions, Realtime, RPCs, Stripe and third-party integrations • Backend and APIs: Node.js, REST APIs, Fastify, gRPC, microservices, webhooks, background jobs • AWS: Serverless Framework v4, CloudFormation, CDK, Lambda, API Gateway, DynamoDB, EventBridge, SQS, Cognito • Google Cloud: Cloud Run v2, Firestore Native, GCS, Pub/Sub, Eventarc, IAM, Cloud Build, Artifact Registry, Terraform • Product Systems: SaaS platforms, marketplaces, admin dashboards, auth, payments, KYC, push notifications, multi-tenant architectures What I Build • AI-powered web and mobile applications with LangGraph pipelines, MCP tool dispatch, LangSmith observability, RAG knowledge bases, and agentic LLM workflows • Firebase and Supabase production backends with secure auth, data models, and server-side logic • Expo and React Native apps with native integrations (payments, KYC, camera, push notifications) • React and Next.js frontends and internal admin dashboards • Custom SaaS platforms, marketplaces, and business applications • API development and third-party integrations (Stripe, identity providers, LLM providers) • Internal tools and enterprise solutions with clean architecture and strong performance Selected Experience • Solo-built Study Forge AI, an open-source agentic AI learning platform. Production runs on Firebase: Auth, Firestore, Storage, Cloud Functions v2, Cloud Tasks, App Check, and rate limiting. Agents run on LangGraph with typed state, repair and critic loops, and Plan-Execute. The workspace agent dispatches tools through in-process MCP, uses a library-scoped RAG knowledge base, streams over SSE, and exports LangSmith traces from Cloud Functions. • Led full-stack delivery on Crowds Now, a production two-sided marketplace (live on the App Store). Built React Native clients for talent and organisations, a Next.js admin dashboard, and a Supabase backend with Postgres, RLS, Edge Functions, Stripe Connect, KYC, push notifications, and marketplace settlement workflows. • Led database and backend design as Technical Project Lead on WRITAB, a live document collaboration platform. Supabase Postgres with Row Level Security on all user-facing tables, security-definer RPCs, Auth with MFA, Fastify REST plus gRPC services, and migrations. • Shipped True Credit HK, an Expo and TypeScript fintech app for a Hong Kong lender, live on the App Store and Google Play. Expo Router, EAS Build and EAS Update, multi-step loan flows, rewards, QR payments, and profile management. • Led delivery as Technical Lead on recent Upwork jobs with 3-4 person product teams: backlog refinement, sprint planning, stories and estimation, architecture decisions, code review, and unblocking juniors, while staying hands-on and shipping features across the stack. • Delivered enterprise-grade systems at BNP Paribas, Citibank, UniCredit, Astek, Prenetics, and EPAM before moving to freelance work. I focus on clean architecture, maintainable code, strong performance, and solutions that create measurable business value. Whether you need a Firebase or Supabase backend, an Expo or React Native app, a React/Next.js frontend, or an AI-enabled product with production agent workflows, I can help turn your idea into a reliable production-ready solution. I am available 40+ hours per week, flexible across time zones, and committed to clear communication with co