Thomas Josso

New York City

• Implement a strict TypeScript monorepo with Turborepo and pnpm: an Expo mobile app (Expo Router) and a Next.js web app (App Router) sharing a tRPC API, Neon PostgreSQL via Drizzle ORM, and Zod v4, for consistent code reuse across web and mobile
• Use TanStack Query and Zustand on mobile, sharing API types from the server through tRPC for end-to-end type safety
• Design authentication with Supabase (Google, Apple, magic-link), with Upstash Redis for sessions, caching, and rate limiting
• Apply CSRF protection, sliding-window rate limits, role-based access control (RBAC), and audit logging in the API layer
• Integrate RevenueCat for native in-app purchases and paywall UI, with server-side access checks and plan-based feature gating
• Implement a debate feature with an XState finite-state machine and Inngest async workflows handling step timeouts, AI turns, stale-session cleanup, and post-debate analysis
• Develop AI chat with the Vercel AI SDK and OpenAI, with streaming responses and Langfuse for prompt management and tracing; layered fallbacks and token limits keep usage within budget
• Integrate Resend for transactional email, Expo push notifications, and Vercel Blob storage for user-generated files
• Combine Sentry for error and performance monitoring, PostHog for web and mobile analytics, and OpenTelemetry metrics exported to Grafana Cloud for real-time visibility
• Use GitHub Actions for CI and EAS for mobile releases, with Vitest API tests

France

• Developed a viable MVP in the first year, then kept the project as a personal lab to explore new technologies
• Designed and built an isomorphic mobile and web app from scratch with React Native and Next.js
• Built a GraphQL API with MySQL and multi-platform CI/CD pipelines, cutting deployment time
• Combined market research, user feedback, and input from a fitness coach to design training features that improved retention

Paris, France

• Delivered features end to end in a React, Next.js, and GraphQL codebase, from technical spec through development, testing, and deployment
• Built across React, Next.js, and React Native for faster load times and a more intuitive UX
• Added Jest and Cypress automated tests in TypeScript, cutting regressions by 8%
• Improved the release workflow and developer experience, cutting release time by 40%
• Resolved incidents and ran migrations with minimal impact on users
• Promoted React and TypeScript best practices, raising code quality across the team

Paris, France

• Implemented React Native tech stack for scalable and rapid delivery
• Created a consistent mobile visual identity, supporting €5M fundraising efforts
• Built a lightweight web app for a retailer demo, leading to partnership discussions
• Set up continuous deployment for iOS and Android, speeding up delivery cycles

Paris, France

• Built France's first bet combinator, expanding available betting options and enhancing user engagement
• Updated the interface for the Spanish market launch, improving user experience and accessibility
• Supervised and mentored three interns during their projects, fostering skill development and ensuring project success

Shanghai, China

• Built a WeChat app for a luxury brand to reach the Chinese market, enhancing brand visibility and customer engagement
• Maintained three e-commerce sites and ran targeted ad campaigns for China, increasing site traffic and boosting sales
• Conducted an in-person project wrap-up with the project manager of a major marketing agency, ensuring final approval and client satisfaction
• Provided user training to support adoption and usage, leading to increased user proficiency and reduced support requests