Senior Full-Stack Engineer (AI Development Platform)

Job Description The Opportunity We're building the AI-powered operating system for the next generation of software creation-where traditional engineers and non-technical builders (think lawyers, designers, and founders) can collaborate, create, and deploy AI-driven applications using plain English. This isn't just another IDE or low-code tool. We're threading an impossible needle: Deep enough for engineers who demand power and flexibility. Accessible enough for domain experts who've never written a line of code. Compelling enough to make both groups wonder how they ever worked without it. If you've ever wanted to architect systems that redefine how software is built-and see your work used by hundreds of thousands of builders-this is your shot. What You'll Do Architect foundational systems for collaborative AI development (think Google Docs meets VSCode, with real-time multi-user editing via Y.js). Build and scale LLM orchestration that actually works-low latency, debuggable, and reliable for both real-time and long-running AI agents. Solve hard problems , like designing an executor that handles arbitrarily long-running agents, scales from zero to thousands in seconds, and remains traceable for end users. Write a ton of code (mostly TypeScript/Next.js) while keeping our AWS/Cloudflare stack humming. Wear multiple hats : debug user issues, make product calls on the fly, and help shape the future of AI development. Who You Are 4+ years of experience building real products used by real people. An AI-curious engineer with hands-on experience building with LLMs (bonus if you've worked on agents or orchestration). Technical chops : Strong TypeScript skills (our whole stack is TS), front-end fluency (React/Next.js), and solid system design intuition. A builder at heart : You've shipped side projects, contributed to OSS, or have a presence that shows you love creating things. Low ego, high output : You fix problems before being asked, care more about users than your code, and thrive in fast-moving environments. Ex-founder/CTO? Even better-our team is stacked with former startup leaders who've raised VC, but we're open to exceptional engineers who just love to build. Nice-to-Haves STEM degree from a top-tier school. Experience with real-time collaboration tools (CRDTs, WebSockets, etc.). A knack for making complex systems feel simple. Traits We Avoid Unfounded arrogance (we're a low-ego team). Poor communicators (we move fast-clear, concise wins). Why Join? Work with ex-CTOs and founders who've built and scaled before. Shape the AI operating system that will define the next era of software. Backed by $30M in seed funding (largest in YC history). 300K+ signups and growing fast. #J-18808-Ljbffr