Jakub Pachocki

Pachocki earned a Ph.D. in theoretical computer science from Carnegie Mellon UniversityCarnegie Mellon UniversityCarnegie Mellon University (CMU) is a private research university in Pittsburgh, Pennsylvania. It grew out of the Carnegie Technical Schools, founded with funding from Andrew Carnegie in 1900, which were renamed the Carnegie Institute of Technology in 1912 and took the present name after merging with the Mellon Institute in 1967. The university is known for computer science, robotics, engineering, and the arts, and has campuses in Qatar, Silicon Valley, and Rwanda. As of September 2025, it enrolled 16,582 students. Its current president is Farnam Jahanian. On September 30, 2026, the university announced a $3 billion gift from Ken Griffin and plans to build a new campus in Miami.Open the full entry and later left an academic career in the field to join OpenAI.⁠[1][2]

Pachocki joined OpenAI in 2017 as a research lead on its Dota team, which built OpenAI Five, an AI system that could defeat human players at ValveValveValve is a video game company based in Washington State, United States. Founded in 1996 by Gabe Newell and Mike Harrington, it developed games including Half-Life and operates the PC game distribution platform Steam.Open the full entry’s strategy game Dota 2. He went on to lead research in the reasoning and science of deep learning organizations and was promoted to principal of research and then director of research.⁠[3][1]

He led the development of GPT-4 and OpenAI Five, worked on large-scale reinforcement learning and deep learning optimization, and helped refocus the company on scaling deep learning systems.⁠[1]

On May 14, 2024, OpenAI announced that co-founder Ilya SutskeverIlya SutskeverIlya Sutskever is a computer scientist who studied under Geoffrey Hinton, helped develop AlexNet and sequence-to-sequence learning, and is a co-founder and former chief scientist of OpenAI. As a board member in 2023 he took part in removing Sam Altman, and after leaving OpenAI in 2024 he founded Safe Superintelligence, which he has led as CEO since 2025.Open the full entry was leaving and that Pachocki would succeed him as chief scientist, a role he had effectively filled since November 2023. Chief executive Sam AltmanSam AltmanSam Altman is an entrepreneur and investor, and the co-founder and chief executive officer of OpenAI. He previously served as president of Y Combinator and founded the location-based social service Loopt. He also helped found Tools for Humanity and Merge Labs, has invested in energy and life sciences ventures, and has driven public discussion of AI governance, employment, and wealth distribution.Open the full entry said: “Jakub is going to be our new Chief Scientist,” adding: “He has run many of our most important projects.”⁠[1][3]

On September 25, 2025, a16zAndreessen HorowitzAndreessen Horowitz (a16z) is a venture capital firm founded in 2009 by Marc Andreessen and Ben Horowitz. It invests from the seed stage through the growth stage and provides operational support to its portfolio companies.Open the full entry released the podcast episode “From Vibe Coding to Vibe Researching: OpenAI’s Mark Chen and Jakub Pachocki,” hosted by Andreessen Horowitz’s Anjney MidhaAnjney MidhaAnjney Midha is an entrepreneur, investor, and researcher, the founder of AMP, and a visiting scientist in applied physics at Stanford University. He co-founded Ubiquity6, led developer platform ecosystem work after the company was acquired by Discord, joined Andreessen Horowitz in 2023 to work on AI investing, and currently serves at the firm as a Venture Partner.Open the full entry and Sarah WangSarah Wang (a16z)Sarah Wang is a venture capitalist and general partner on the growth team at Andreessen Horowitz (a16z). She joined a16z in 2019 and leads growth-stage investments in AI, enterprise applications and infrastructure, having invested in companies including Character.AI, Wiz, Cursor, Temporal and Exa.Open the full entry, with Pachocki and OpenAI chief research officer Mark Chen as guests.⁠[4][5]

The episode discussed how GPT-5 combines fast responses with long-horizon reasoning, how to measure progress once benchmarks saturate, reinforcement learning, stability tradeoffs in agentic systems, how coding models affect software development, and OpenAI’s longer-term bet on an “automated researcher” that generates new ideas with real economic impact; it also covered compute allocation, hiring and protecting fundamental research inside a product company.⁠[4]

Pachocki and Ilya Sutskever are among the key architects of OpenAI’s reasoning models, in particular o1 and o3.⁠[2]

Pachocki has competed in international coding contests and prefers shorter problems with concrete solutions; competitive programmer Przemysław Dębiak (Psyho), a friend, previously worked with him at OpenAI. Speaking of a recent programming competition entered by an OpenAI model, he said: “So I was seriously invested in the performance of this model in this latest competition.”⁠[2]

X: Public account: https://x.com/merettm (opens in a new window).⁠[4]