Joshua V.

Production systems that hold up with real users, real money and real data: payments, Postgres, migrations off platforms you don't own, and AI agents that can't talk their way into a database write. Recent: I took over a fragile AI-built app with thousands of live users and payments, hardened its security, moved it onto infrastructure the client owns, rebuilt the payment flow, then stayed on for monthly maintenance. 5.0 reviews. Client: "Working with Josh was the best decision I made for this project." What I ship: → Payments: Stripe integrations, signature-verified webhooks, idempotent credits, append-only ledgers with reversals, and reconciliation against the processor. I find the double charges that hide in retries. → Migrations: moving a live app between hosts, databases and storage with before-and-after snapshot compares, reconciliation to the cent, and a rollback plan that gets tested before the switch. → AI app rescue: audit, security fixes and migration off Bubble, Replit, Lovable, Bolt, Base44, v0 and Cursor builds onto a stack you own. → AI agents with tool calling: the model plans, deterministic tools act, and money or data changes sit behind checks the model can't talk its way around. → Claude Code every day, with a real review process: one change, one test, and a second pass that tries to disprove the claim before it ships. → Claude API and MCP servers, RAG with citations, integrations across Stripe, HubSpot, Slack and third-party APIs. How I work: short, capped milestones you can test yourself. Code in your GitHub, every account under your login. Eastern time, business hours. Send me the repo, the spec or a screenshot. I'll reply in writing with what's wrong or what it takes, before we talk price. Stack: TypeScript, Node, Express, React, PostgreSQL, Python, FastAPI, Flask, Claude API, OpenAI, Docker, AWS, GCP, Vercel, Railway, Cloudflare. =========================================================================== Stripe • Payments • Webhooks • Payment Processing • Ledger • Reconciliation • Data Migration • PostgreSQL • Node.js • Express • TypeScript • React • Python • FastAPI • Flask • Claude Code • Claude API • Anthropic API • AI Agents • Agentic Workflows • Tool Calling • MCP Server • Model Context Protocol • Tool Use • Structured Output • LLM Systems • RAG • Vector Databases • ChromaDB • Qdrant • LangChain • LangGraph • Ollama • Docker • AWS • GCP • Vercel • Railway • Cloudflare • Bubble Migration • Replit Migration • Lovable Migration • Bolt Migration • Base44 Migration • Security Hardening • Code Review • Async APIs • Data Pipelines • API Integration • App Rescue • Production AI