Closed — Private source — described by architecture only2026 — now
Full-stack developer
- Client
- A learning platform where members take AI courses, ask an assistant trained on the whole course library, earn certificates, and talk to each other in one community.
- Recruiter
- Next.js 14 front end and a Node/Express API over Prisma and Postgres. RAG assistant, Stripe subscriptions, real-time community, certificates, and the admin analytics behind them.
- Engineer
- Express API with a repository/service split over Prisma and Postgres. Redis carries presence and caching, ChromaDB carries retrieval, Bull carries anything scheduled, Socket.IO carries the live surface.
What it does
- Courses, cohorts and certificates delivered to paying members
- Subscription billing, invoices and failed-payment recovery
- A community members actually post in, with live presence
- Admin analytics that answer who is at risk of leaving, and why
Under the hood
- RAG assistant over the course library with a bounded function-calling loop, so it reports real member data instead of inventing metrics
- Stripe webhook lifecycle mirrored into an invoices table — idempotent, and the first payment is counted correctly
- Socket-driven presence roster in Redis; last-login timestamps proved unreliable, so activity is derived from connections
- One email transport with an observer tap, so every send is logged and body-redacted without touching a single call site
- Hand-written idempotent migrations — the production database cannot be reset
Built with
- Next.js 14
- TypeScript
- Node.js
- Express
- Prisma
- PostgreSQL
- OpenAI
- LangChain
- ChromaDB
- Redis + Bull
- Socket.IO
- Stripe
- AWS S3/CloudFront
- Docker
- Sentry
- Cypress