Senior Architect / Full-Stack Engineer — build & launch a mobile product (hands-on, AI-agent-driven)

About the project: We're building a mobile-first product in the prediction / gaming space, aimed at emerging mobile-first markets. The money core already exists — a TypeScript/NestJS modular monolith on Postgres (Drizzle ORM), phone+OTP auth, and a concurrency-safe double-entry wallet ledger. We're now pushing toward production launch. I'm the founder and I work hands-on in the codebase daily using Claude code. I'm looking for a senior engineer to architect alongside me, take responsibility over production grade and ship with me. Independent freelancers only — no agencies or dev shops. I want to work directly with the person writing and reviewing the code, not an account manager fronting a team. What you'll own: 1. Architecture for speed, not for show. Design the right stack and structure to launch fast — monorepo, modular monolith, boring proven tools. Explicitly NOT a microservices "spaceship." We assume we'll re-architect for scale in 6–12 months; getting to market and learning comes first. 2. Architecture for product agility. In this space you don't win on ad spend — you win on shipping and testing user journeys faster than anyone else. Your design must make it cheap to experiment with funnels (registration, deposit, core flow, retention) and pivot on KPIs. Server-driven config, feature flags, fast iteration loops. 3. AI-agent-driven delivery. We build with Claude Code agent swarms. Your job is to set the architecture, conventions, tests, and guardrails so agents ship correct code fast — and to review what they produce. You should be excited about AI-assisted development, not skeptical of it. 4. Integrations. Local mobile-money wallets (fast deposits and sub-5-minute withdrawals) and a third-party games aggregator (incl. instant / real-time games). 5. Real-money correctness. Idempotency, ledger integrity, reconciliation, concurrency safety. This is people's money. Must-have experience: 1. Senior full-stack or backend, with real ownership of production launches (not just feature tickets). 2. TypeScript + Node, Postgres, modern ORM (Drizzle/Prisma/TypeORM); NestJS a strong plus. 3. Built and operated real-money / payments / fintech / wallet-ledger systems 4. Comfortable being hands-on and pairing daily — you write and review code, not just diagrams 5. Fluent English; available for a daily standup with me (timezone overlap with GMT+3) Strong pluses: 1. Mobile-money rails or payment-aggregator integration in emerging markets. 2. Hands on Experience with AI coding agents (Claude Code, Cursor) in a real production codebase 3. Real-money gaming, prediction-markets, or regulated-product experience 4. Building for low-bandwidth / low-end Android markets (Opera Mini, tiny payloads, SSR/light-JS) 5. Comfortable with regulated real-money products (you're OK working in this space). How to apply Don't send a generic proposal. Tell me: A production system you architected for speed to launch, and one thing you deliberately left simple (and later had to refactor). Your honest take on building with AI coding agents — where they help and where they bite. A real-money/payments system you've worked on and how you guaranteed correctness. Start your proposal with the word "LEDGER" so I know you read this — and confirm you're applying as an independent freelancer, not on behalf of an agency. We'll start with a small paid trial task before any long-term commitment.