Jonas Templestein

Jonas Templestein is a German-British software engineer and entrepreneur. He is the CEO and Founder of Iterate, an AI agent platform, and the co-founder and former CTO of Monzo Bank, one of the UK's leading digital banks. He is active on X as @jonas.^[1]

Career

Early Career

Templestein studied Management Consulting at Academy Consult München (2007–2009) and at the University of California, Berkeley (2009). He worked as a Lead Engineer at Campfire Labs (acquired by Groupon), Director of Experience at StartupBus, NLP Researcher at LEKAB Communication Systems, and Software Engineer at Starling Bank.^[2]

He founded HipDial in 2012, a communications startup he ran until 2018.

Monzo Bank (2015–2023)

In 2015, Templestein moved to London to co-found Monzo (originally Mondo) alongside Tom Blomfield, Jason Bates, Paul Rippon, and Gary Dolman. He served as Co-founder and CTO for nearly nine years, playing a central role in building the engineering foundations of what became one of the most important European fintech companies. Monzo grew to millions of customers and a valuation exceeding £4 billion.^[3]

He left Monzo in December 2023, writing a farewell blog post after almost nine years.^[1]

Iterate (2024–present)

Templestein founded Iterate in 2024 — described as "the world's most hackable AI agent" — with a mission to enable "self-driving startups" where AI handles routine business operations. Iterate is backed by OpenAI, Index Ventures, Y Combinator president Garry Tan, Naval Ravikant, Amjad Masad (Replit CEO), Aravind Srinivas (Perplexity CEO), and others.^[4] He has been vocal about a theory of "Level 0 through Level 5" AI-augmented startups, placing most organisations at Level 1 as of 2025.

Connection to Jan

In May 2025, Jan did a trial week with Iterate at a rate of $3,600 for the week (with a potential offer of $5,000+/month ongoing). Jonas wanted Jan full-time, but Jan declined to continue because Jonas required full-time commitment rather than the 2 days/week arrangement Jan was seeking. Jan had met Jonas at an Amsterdam event earlier in the year.^[5]

cf-artifact-viewer (April 2026)

On April 22, 2026, Templestein published cf-artifact-viewer (iterate/cf-artifact-viewer) — a Cloudflare Artifacts browser and editor that can be deployed to a user's own Cloudflare account with one click. He posted on X: "you should now be able to deploy this to your own Cloudflare account with one click." Jan browsed the GitHub repository and the live demo at artifacts.iterate-dev-jonas.com, continuing to evaluate Cloudflare_Artifacts as potential infrastructure for Self-Driving_Repos.^[6]

Cloudflare Bindings-as-API-Wrappers Idea (April 2026)

On April 24, 2026, Templestein posted an influential idea on X: "The cloudflare 'bindings instead of env vars' thing is so good that I sometimes wonder why they don't have wrappers for popular third party APIs — env.STRIPE — that sort of thing." He followed up with a technical approach: using lightweight wrapper Workers and service bindings, so tokens never leak. Jan liked the tweet. Cloudflare's Irvine Broque responded with interest, calling it the "next fun collab" and suggesting OAuth-based Stripe integration where "it's literally impossible to leak the API token."^[7]

This is notable because it connects directly to the infrastructure layer both Templestein and Jan operate in — Cloudflare Workers as the substrate for agent-friendly services — and represents a potential new Cloudflare product direction that could benefit both Iterate and Jan's Cloudflare-based projects.

See Also

• Jan_Wilmake
• Iterate
• Cloudflare_Artifacts