Full-Stack Engineer

The site is a Node.js and Express application rendering Pug on the server, with Vue 3 for the interactive parts and Socket.IO for real-time multiplayer. Quizzes are generated with OpenAI and validated with Zod. Authentication and user data are on Firebase; sessions and blog content on MongoDB; the whole thing runs on Railway. There is also a Flutter app on both stores with an in-app purchase for multiplayer hosting.

There is one engineer today - the founder - and the codebase has the honest rough edges of something built by one person over six years. You would be the second, with real ownership over the roadmap and the backlog of things that ought to be better.

What you will do

• Ship features across the full stack: routing and controllers, Pug views, Vue components, Sass, and the Socket.IO multiplayer layer.
• Harden the multiplayer engine - server-side validation of room state and scores, reconnection, and the bits that currently trust the client.
• Improve the quiz generation pipeline: prompt versioning, caching, cost control, and the evaluation hooks the data scientist needs.
• Own the security backlog: secret rotation into environment variables, content security policy, session cookie settings, and rate limiting.
• Keep the Flutter app in step with the web API, including the purchase verification path.
• Take part in the on-call rotation, which is two people and rarely rings.

What we are looking for

• Five or more years building and running production web applications, with at least three in Node.js.
• Strong on Express, server-rendered templating and a modern front-end framework - Vue preferred, React fine.
• Real experience with WebSockets or Socket.IO in production, including the failure modes.
• Comfortable with MongoDB and a document store such as Firestore, and with deploying to a PaaS.
• You write clear commit messages and clearer comments, and you leave code better than you found it.

Nice to have

• Flutter or another mobile stack.
• Working with LLM APIs in a product - structured output, validation, cost management.
• Sass, Gulp, and the pragmatism to tolerate a build pipeline that is not Vite.