Software Engineer

Software Engineer - Stealth AI Startup (London / Paris / Europe) (RL/Reinforcement Learning)

Package: £100,000-£200,000 + strong early-stage equity

Location: London/Paris hubs, or elsewhere in Europe with occasional travel to be with the team (remote friendly/hybrid - however you like to work)

Bloom have partnered with one of the fastest-growing AI companies in Europe to help them hire their next phase of Software Engineers - a rare opportunity to join a team at this stage, with super strong traction and building at incredible pace. Roles like this don't come around often.

This business is led and founded by a proven founding team with a super impressive and strong track record of building, scaling, and successfully exiting tech companies - with a very strong technical pedigree

They're building the infrastructure for the next generation of AI - where agents don't just learn from static data, but through active experience. Think interactive, resettable digital worlds where AI can explore, act, and learn - from simple websites to complex applications.

This is your chance to help build the digital training ground for foundational AI Agents

The Opportunity

• Join as one of the first 10 engineers and play a pivotal role in shaping the core systems that power this new AI paradigm.

• You'll design and build foundational infrastructure - scalable APIs, distributed systems, and high-fidelity simulations, that enable AI agents to learn through trial and error.

• You'll work in a tight feedback loop with AI researchers, turning cutting-edge ideas into production-ready systems used by leading Frontier labs.

You Might Be a Fit If You

• Have deep experience building scalable, cloud-based systems (AWS or GCP)
• Are fluent in typed languages such as TypeScript/Node.js, Python, Golang etc and are pragmatic about using the right tool for the job
• Have led complex engineering projects from concept to delivery
• Thrive in fast-paced, high-agency startup environments
• Bonus: experience with LLM applications

If you're excited by the idea of building the simulation layer for intelligent agents, this is one of those rare moments where you can shape an entirely new category of AI infrastructure.

Please apply or DM me for details - they're still in stealth, so we'll share more privately