[ Learn ] # Who founded TypeSafe AI? The team behind Jev Who founded TypeSafe AI, maker of Jev: Diogo Almeida, Erik Gafni and Sasha Sheng. What the company and press reports say about each. Checked 1 November 2026. Published 1 November 2026By Jev Hub [Back to Learn](https://jevhub.io/learn) [ TLDR ] - TypeSafe AI, the San Francisco company that makes Jev, was founded by Diogo Almeida, its chief executive, together with co-founders Erik Gafni and Sasha Sheng. - Almeida wrote the Jev launch post on 15 September 2026, and TypeSafe's documentation calls him a cofounder. - The co-founders' names come from reports of the seed round by SiliconANGLE, Dealroom and Value Add VC; we could not open the company's own press release, and we found no title or background for Gafni or Sheng in a source we trust, so we give none. - What the company says about Almeida's earlier work at OpenAI is its own account, which we have not independently confirmed. ## The founders at a glance | | What is known | Where it comes from | | --- | --- | --- | | Diogo Almeida | Founder and chief executive of TypeSafe AI; the documentation calls him a cofounder. Says he helped build instruction-following methods at OpenAI, and the documentation says he co-invented RLHF | TypeSafe's launch post and AI primer (his and the company's own claims) | | Erik Gafni | Named as a co-founder. No title or background that we could confirm | SiliconANGLE, Dealroom and Value Add VC, reporting the seed round | | Sasha Sheng | Named as a co-founder. No title or background that we could confirm | SiliconANGLE, Dealroom and Value Add VC, reporting the seed round | | The company | TypeSafe AI, San Francisco, maker of Jev; came out of stealth on 15 September 2026 | TypeSafe's own pages | | On X | Almeida posts as @CompleteSkeptic; the company as @typesafeai | Their own accounts | Read on 1 November 2026. Statements about Almeida's earlier work are TypeSafe's and his own claims, labelled as such, and this site has not independently confirmed them. The co-founders' names come from press reports of the seed round, not from a page we could open at the company. We give no detail we could not source. ## Who founded TypeSafe AI? TypeSafe AI was founded by Diogo Almeida, its chief executive, with co-founders Erik Gafni and Sasha Sheng. Three outlets that reported the company's $40 million seed round, SiliconANGLE, Dealroom and Value Add VC, name all three. SiliconANGLE adds that the two co-founders also have extensive AI experience, without giving more detail. TypeSafe's own pages that we could read name Almeida: his byline is on the launch post, which calls him founder, and the documentation calls him a cofounder. We could not open the company's press release, so the two co-founders' names are as reported rather than confirmed by us. We found no title or background for them in a source we trust, so we give none. - [TypeSafe AI: the company behind Jev](https://jevhub.io/typesafe-ai) ## What does the company say about Diogo Almeida? In the launch post he says that after two years in stealth the company released its first System One model, Jev, on 15 September 2026. He says that at OpenAI he helped build the methods that made language models useful at following instructions and talking with people, and that this work ended up as the research behind ChatGPT. TypeSafe's AI primer goes further: it says RLHF was used to train InstructGPT and ChatGPT and was co-invented by him, and links to his Google Scholar page. Both are the company's own statements about its founder. Press coverage calls him a former OpenAI researcher, which fits, but we have not checked the details against OpenAI. The path to Jev, as the launch post tells it. From TypeSafe's launch post of 15 September 2026 and Modal's Runtime 2026 talk. The first step is the founder's own account. - [What is a System One model?](https://jevhub.io/what-is-a-system-one-model) ## What do we know about the co-founders? Less, and we say so. Erik Gafni and Sasha Sheng appear by name in the seed-round coverage as co-founders, and nowhere else that we could verify. Some profile and wiki sites list titles and earlier employers for them, but those sites do not cite the company or a primary source, so we do not repeat them. If TypeSafe publishes a team page or a press release naming their roles, this article will be updated with it and dated. - [TypeSafe raises $870M](https://jevhub.io/updates/typesafe-raises-870-million-series-a) ## Where can you hear from the team? Two long recordings of Almeida are listed on this site: a talk at Modal's Runtime 2026 conference, published on 6 October 2026 and about 13 minutes long, and a long interview with the Latent Space podcast, published on 21 September 2026. He posts on X as @CompleteSkeptic and the company posts as @typesafeai. We found no recordings or accounts that TypeSafe itself points to for the co-founders. A post by a founder is a company statement, so we treat it as a claim until a primary page, such as the documentation or blog, confirms it. - [The Latent Space interview](https://jevhub.io/builds/latent-space-diogo-almeida) ## Our read People check who is behind a model before they build on it. Here the answer is three named founders, a chief executive with a stated research background at OpenAI, and a company that has raised a large amount in a short time. Only one of the three has material of their own that we can read, so most of what is known is about him. That is the company's story and the press's, and it should not stand in for testing. Judge Jev on your own data, and treat what any founder says as a claim to check. - [How to use Jev](https://jevhub.io/how-to-use-jev) ## Common questions Diogo Almeida, the chief executive, with co-founders Erik Gafni and Sasha Sheng, according to reports of the company's seed round by SiliconANGLE, Dealroom and Value Add VC. TypeSafe's documentation also calls Almeida a cofounder. Erik Gafni and Sasha Sheng, as named in press reports of the seed round. We could not open the company's press release and found no title or background for either in a source we trust, so we give none. Diogo Almeida is the founder and chief executive. He wrote the launch post for Jev, published on 15 September 2026. In the launch post he says he helped build, at OpenAI, the methods that made language models follow instructions, which became the research behind ChatGPT. That is his and the company's account, which we have not independently confirmed. TypeSafe's AI primer says RLHF was co-invented by him. That is the company's claim about its cofounder, and we have not verified it ourselves. On 15 September 2026, after about two years in stealth, according to the launch post Almeida wrote. Almeida appears in his Runtime 2026 talk for Modal, published on 6 October 2026, and in a Latent Space interview published on 21 September 2026. Both are on YouTube. ## Sources Written by Jev Hub from the sources below and checked against them on 1 November 2026. Where a figure is a company's own claim, the article says so. - [TypeSafe blog: Introducing System One Models & Jev (15 September 2026)](https://typesafe.ai/blog/introducing-system-one-models-and-jev) - [TypeSafe docs: AI primer (read 1 November 2026)](https://docs.typesafe.ai/introduction/machine-learning-primer) - [SiliconANGLE: TypeSafe AI exits stealth with $40M (16 September 2026)](https://siliconangle.com/2026-09-16/typesafe-ai-exits-stealth-with-40m-to-build-ai-for-use-by-software/) - [Dealroom: TypeSafe exits stealth with $40M seed](https://dealroom.co/news/151032-typesafe-exits-stealth-with-40m-seed-to-build-ai-for-software-not-people/) - [Value Add VC: TypeSafe AI $40M seed and stealth launch](https://valueaddvc.com/pulse/typesafe-ai-40m-seed-stealth-launch-2026) - [Modal on YouTube: Diogo Almeida at Runtime 2026 (published 6 October 2026)](https://www.youtube.com/watch?v=ip7Qej0ONoE) - [Diogo Almeida on X (@CompleteSkeptic)](https://x.com/CompleteSkeptic) ## Related content - [What is Jev?](https://jevhub.io/what-is-jev) - [How to use Jev](https://jevhub.io/how-to-use-jev) - [Jev pricing](https://jevhub.io/economics)