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Substack is a Y Combinator company in the Winter 2018 batch. Its directory entry describes it as: A place for independent writing. The founders listed are Chris Best (Founder/CEO), Jairaj Sethi (Founder), Hamish McKenzie (Founder/COO) (Y Combinator directory entry, November 9, 2017).
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New accelerator entry · 2017-11-09 · the record
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Most-starred repository: universal-constructor — 25 stars, JavaScript.
Counted 2026-09-27 across repositories the account owns; forks are excluded.
Checked away from the directory entry. Neither line below comes from the company's Y Combinator page.
The app for independent voices
The title and description the site itself served, answering 200. Not a cached copy and not the company's directory entry — what was live when we asked.
Counted only where a thread links to this company's own site, announces it by name on that forum, or names it beside its own Y Combinator batch. A thread whose title merely carries the words is not counted — a name is not an identifier. More may exist than the one page of results read here. Hacker News is not us, and nothing above is our opinion of the company.
Founders, titles and bios as the company published them. Photographs are our own copies of the ones on that record, so they do not break when the original link expires.
No investor is drawn from a Form D — the form states how many invested and never who. The one investor on this graph is named because a batch has exactly one.
Example from a real report (our sample on Target): “Target eliminated approximately 1,800 corporate positions, with around 1,000 employees receiving layoff notices and the remainder accounted for by eliminating open roles.” Source: NBC News
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Sourced from the company's Y Combinator directory entry, from the company's own site, read directly on 2026-09-27 (substack.com), from the public GitHub account that record links to (substackinc), and from Hacker News, where 98 threads met the matching rule stated beside the count.
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