Founding Engineer M/F/X - Build autonomous companies.

Twin is the AI company builder. Anyone can describe a business goal in plain English — our platform designs, builds and operates AI agents that execute work end-to-end, using APIs when they exist and browsers when they don't. Our agents don't just answer questions: they browse websites, call APIs, recover from failures, remember what matters, and become cheaper and more reliable over time. Over 70,000 businesses already run real workflows on Twin every day.
We're a small team of repeat founders and senior engineers based in Paris. We've raised a $10M Seed led by LocalGlobe and are building one of the most ambitious AI infrastructure companies in Europe.

Job Description :

Most AI companies build copilots. We're building autonomous systems that run real businesses — and you'll build the core systems behind them. Your work will span the entire product, from low-level Rust infrastructure to user-facing experiences.
Typical projects include:

- Building ultra-low latency browser automation
- Designing reliable execution engines for long-running autonomous tasks
- Creating fault-tolerant distributed systems that recover automatically
- Building memory systems that improve over time
- Designing agent capabilities that thousands of users rely on every day
- Shipping product features from idea to production

You'll own problems, not tickets.
Why join? You'll work on problems that don't have existing solutions, ship code that reaches production immediately, and help define both the product and the architecture, alongside engineers who care deeply about quality without sacrificing speed.

Profile / Requirements :

We're looking for engineers who love building products as much as building systems. You likely have:

- Deep production Rust experience
- Experience building products in startups or open source
- Strong systems fundamentals (concurrency, networking, performance, distributed systems)
- Excellent product intuition, high ownership and a bias toward shipping
- Heavy usage of AI coding assistants
- Curiosity to work across the entire stack when necessary

You might be a great fit if you've built an open-source project people actually use, designed APIs developers enjoy, taken products from idea to production, talked directly to users, or optimized systems because performance mattered.
We care far more about what you've built than your years of experience.
We'd love to see
• Open-source projects.
• GitHub activity.
• Technical writing.
• Developer tools.
• Systems software.
• Products you've built from scratch.