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Greater London, England, United Kingdom
Onsite
Available
Isidor is building the foundation of reliable AI. We believe that the next leap in AI depends as much on understanding and measuring model behavior as it does on model size. To make AI trustworthy, we need systems that verify outputs, benchmark performance, and automate evaluation across billions of examples.
Isidor was founded by engineers and researchers who care deeply about precision, transparency, and scientific rigor. We are a small, fast-moving team working directly with frontier AI labs and enterprise to make evaluation as measurable and reproducible as training itself.
Founded in September 2025, Isidor raised an oversubscribed $3.6m pre-seed from leading funds including Gradient Ventures, futurepresent and Seedcamp, along with angels from Google DeepMind, Perplexity, Motive, Episode 1 and more.
As a Founding Engineer, you’ll own the architecture that defines how AI reliability is measured, from scalable backend systems to forward deployed pipelines and client-facing APIs.
You will:
Bonus points if you have:
Your work will directly influence the development of the next generation of AI models, giving you the opportunity to make an outsized impact on frontier research and implementation in enterprise.
Our momentum: 0 → 7 figures in revenue in <1 month
Backed by: Gradient Ventures, futurepresent, Seedcamp, along with angels from Google DeepMind, Perplexity, Motive, Episode 1 and more
Employment Type: Full time, in-office
Location: London (in-person), with potential for relocation to San Francisco in H1 2026 (with visa support)
Compensation: Competitive salary + equity
Please reach out with any questions to founders@isidor.ai
