Tom Preston-Werner
About Tom Preston-Werner
Tom Preston-Werner was born in Dubuque, Iowa, and attended Harvey Mudd College but did not finish. Crunchbase lists him as a software developer at Active Network (2006 to 2007) and at Powerset (2007 to 2008). Powerset was later acquired by Microsoft. He co-founded GitHub in 2008 with Chris Wanstrath and P. J. Hyett and served as CEO and CTO until April 2014. Wikipedia reports that he resigned in 2014 after an internal investigation concluded that he and his wife had harassed an employee. Microsoft acquired GitHub in 2018 for $7.5 billion in stock.
He created Jekyll, a static site generator first released in 2008, and is credited with Semantic Versioning (SemVer), TOML and Gravatar. He also created RedwoodJS, a full-stack JavaScript framework that he announced on X. After GitHub he was co-founder and strategic advisor at Codestarter (2014 to 2015) and co-founded the language-learning company Chatterbug. He has sat on the board of Netlify, and his X profile lists Hack Club and Mote among his boards.
In 2019 he and his wife, Theresa Preston-Werner, started Preston-Werner Ventures (PWV). Crunchbase lists him there as co-founder and general partner. He is based in Ross, California.
Before PWV, Preston-Werner invested as an individual angel. A conference speaker bio described his angel and philanthropic thesis as focused on fighting climate change. PWV's Crunchbase profile says the firm funds projects at the intersection of social justice, climate change and technology. It lists two funds, including a Rolling Fund. On October 22, 2025, his personal site posted an announcement titled "Announcing PWV Fund I". Fund size is not stated in the sources I reviewed.
Investment counts differ by source and date. Lounge's Crunchbase-based count is 27 investments, with 0 lead investments and 0 exits recorded. Another version of his Crunchbase person page shows 54 investments, Tracxn lists 50 portfolio companies, and PitchBook lists 71 investments. Tracxn names Netlify, Supabase and Weights & Biases among his notable investments, and it lists Weights & Biases, Ready Player Me, OpenPipe and Cohort as portfolio exits.
Crunchbase shows 15 AI investments since 2023. The AI portfolio there includes Zed Industries, Ideogram, Flux, Strix, OpenPipe, Command Code, Liquid AI, Milestone, l'école, Zoo, Elicit and AppFlowy.
Public announcements and trackers confirm several of these with dates. He was among the angels in Zed's $10 million Series A in March 2023, which Redpoint Ventures led. He joined Ideogram's seed round in August 2023, which Andreessen Horowitz and Index Ventures co-led. Crunchbase also records OpenPipe's seed round in March 2024 and Command Code's round in August 2024. Other AI-related rounds on his Crunchbase timeline include Alinia AI (2024), Not Diamond (July 2024, seed), Sourcetable (March 2025) and Milestone (November 2025). Strix's seed round is the most recent entry on the Crunchbase profile I found.
Most of his recorded deals are early-stage rounds. Crunchbase and Tracxn label them seed or pre-seed. Some are Series A or later, such as Zed's Series A. Tracxn describes his top sectors as enterprise applications and enterprise infrastructure. His AI deals lean toward developer tools, AI infrastructure and generative AI products. Tracxn lists most of his investments as being in the United States, with others in Germany and other countries.
He has not published a check size or ownership target that I could find, so none is given here. PWV's stated areas are social justice, climate change and technology. I found no public statement from him on how he evaluates AI pitches, and no public pitch process. His personal site and X profile are the places where he posts about his work.
- Zed Industries: high-performance, collaborative code editor. He was an angel in its $10M Series A in March 2023.
- Ideogram: generative text-to-image platform. He joined its seed round in August 2023.
- OpenPipe: AI platform for developers to build datasets and fine-tune models. Seed round in March 2024.
- Command Code: listed in his Crunchbase AI portfolio. Round dated August 2024.
- Not Diamond: seed round in July 2024.
- Alinia AI: round in 2024 on his Crunchbase timeline.
- Sourcetable: seed round in March 2025.
- Milestone: seed round in November 2025.
- Strix: seed round, his most recent Crunchbase entry.
- Flux: in his Crunchbase AI portfolio. His timeline shows a Flux round on October 13, 2021.
- Liquid AI, l'école, Zoo, Elicit, AppFlowy: listed in his Crunchbase AI portfolio. Dates not confirmed.
- Supabase and Netlify: non-AI developer infrastructure companies that Tracxn lists among his notable investments.
- crunchbase.com/person/tom-preston-werner
- crunchbase.com/person/tom-preston-werner/person_overview_investor/time
- crunchbase.com/organization/preston-werner-ventures
- en.wikipedia.org/wiki/Tom_Preston-Werner
- tom.preston-werner.com
- x.com/mojombo
- techcrunch.com/2023/03/15/zed-code-editor-raises-10m
- thesaasnews.com/news/ideogram-raises-22-3-million-cad-in-seed-round
AI portfolio
Investing activity
Tom Preston-Werner has made 27 investments according to Crunchbase. 15 of those investments since 2023 were in AI companies, including Zed Industries, Ideogram, Flux, Strix and OpenPipe.
Tom Preston-Werner appears in 1 AI deal tracked by the Lounge deals desk. The rounds are mostly Seed, with a median round size of $7M. The most recent is Strix (Seed, $6.7M, Jun 2026).
Tom Preston-Werner most often invests alongside Heavybit, Daniel Liem, Kareem Amin and Maza Ventures, and the companies they back on Lounge are mostly in AI.
Deals
Frequently asked questions about Tom Preston-Werner
Does Tom Preston-Werner invest in AI startups?
Yes. Crunchbase shows 15 AI investments since 2023, including Zed Industries, Ideogram, OpenPipe, Strix and Command Code.
What stage does Tom Preston-Werner invest in?
Most of his recorded deals are seed or pre-seed rounds. He has also joined later rounds, such as Zed's $10M Series A in 2023. Crunchbase records 0 lead investments for him.
What is Tom Preston-Werner's check size?
No check size is public. Sources list some round sizes but not his own amount, so founders should not assume a figure.
Who is Tom Preston-Werner?
He is a co-founder and former CEO of GitHub, the creator of Jekyll and RedwoodJS, and a co-founder of Chatterbug. He is also co-founder and general partner of Preston-Werner Ventures.
How can founders contact Tom Preston-Werner?
He is active on X as @mojombo and has a LinkedIn profile and a personal site. No public pitch process or submission form was found.
Is Tom Preston-Werner an angel investor?
Yes. Tom Preston-Werner invests personally as an angel. Crunchbase counts 27 investments.
What AI companies has Tom Preston-Werner invested in?
Tom Preston-Werner's AI investments include Zed Industries, Ideogram, Flux, Strix, OpenPipe, Command Code, Liquid AI and Milestone. The 1 round on Lounge are listed on this page with amounts, dates and co-investors.
Where is Tom Preston-Werner based?
Tom Preston-Werner is based in Ross, United States.
What stage does Tom Preston-Werner invest at?
In the rounds tracked on Lounge, Tom Preston-Werner has invested at Seed, with a median round of $7M.
Who does Tom Preston-Werner co-invest with?
Tom Preston-Werner's most frequent co-investors on Lounge are Heavybit (1 deal), Daniel Liem (1 deal), Kareem Amin (1 deal), Maza Ventures (1 deal) and Ivan Burazin (1 deal).