How Chroma Grew on GitHub: From an Active Learning Library to an $18 Million Seed

Chroma started as a library for active learning

The chroma-core/chroma repository was created on 5 October 2022. At the end of that year its README described something other than a database: "Chroma is a python library for implementing active learning." It added that the project was in alpha and that the API "may incur rapid breaking changes."

The company had already raised money. When Chroma announced its seed, it also announced a pre-seed from May 2022, led by AIX Ventures, Bloomberg Beta and AI Grant. The founders, Jeff Huber and Anton Troynikov, wrote that Chroma began with the idea that "models can be understood through interpretability of their latent spaces", and that they built the database because they needed one for that work.

The oldest of the stars it has today date from December 2022, when it gained five.

The launch and the seed came seven weeks apart

Chroma launched on Valentine's Day 2023. In the Show HN post for its cloud product two years later, Huber wrote that in December 2022 he had messaged every person who tweeted about embeddings that month, and that there were only 120 of them.

The repository moved fast after the launch. It gained 360 new stars in February, 507 in March and 3,201 in April. The number of people opening and merging pull requests went from 9 in February to 33 in April.

On 7 April 2023 Chroma announced an $18 million seed led by Astasia Myers of Quiet Capital, with angels including Naval Ravikant, Guillermo Rauch and Amjad Masad. Business Insider reported a $75 million valuation. The announcement counted 35,000 Python downloads in the month before it.

By June the README had a new first line: "Chroma - the open-source embedding database. The fastest way to build Python or JavaScript LLM apps with memory!" It kept that line until 2026.

Stars never returned to the seed month

April 2023 is still the repository's best month for new stars. 2023 brought 9,805 in total. 2024 brought 5,875, the fewest of any full year, and 2025 brought 9,184. 2026 has brought 4,642 to 16 October, and since July the repository has gained about 300 a month, its slowest months since the launch.

New GitHub stars on chroma-core/chroma per calendar year, from 9,805 in 2023 to 5,875 in 2024 and 9,184 in 2025. 2026 is counted to 16 October.

The engineering did not follow the stars. In 2024 the default branch took a third more commits than in 2023 while new stars fell by 40%. Commits rose by almost 80% in 2025, to 1,798. The number of people on pull requests in the busiest month stayed between 26 and 33 through 2025. It rose to 56 in July 2026. Of those 56 accounts, 37 opened a single pull request that month, and 12 have had one merged.

Over the same years the database moved to Rust. The first Rust code landed in December 2023, version 1.0.0 shipped in April 2025, and Rust is now 71% of the repository's code by GitHub's language count. Python, the language of the 2022 library, is 15%.

The hosted product took two years longer than planned

The seed announcement said Chroma was building a distributed system for a hosted product. SiliconANGLE reported that the managed version was set to launch in the third quarter of 2023.

It launched publicly on 19 August 2025, as Chroma Cloud, on a distributed database written in Rust. Huber wrote that it had been in private beta for a year and that the team held it back until they were "extremely confident in the system." In the same post he put the open-source project at more than 21,000 stars and 5 million monthly downloads.

The launch month was the repository's second-best month for new stars: 1,423, against 640 in July. By the end of 2025 the README had a Chroma Cloud section above the API, and by mid-2026 its first line no longer said "embedding database."

The pre-seed closed in May 2022 and was announced with the seed. We found no round announced after April 2023.

The repository was loudest before the product it now sells

Chroma's early signal was easy to see: a README that changed from an active learning library to an embedding database, a launch followed by 3,201 new stars in its third month, and a seed announced in that same month. Anyone reading the repository in April 2023 saw the attention.

What came next was harder to read from GitHub. Stars rose with announcements, the seed and then the Chroma Cloud launch, and fell back between them. 2024 had the fewest new stars of any full year and a third more commits than 2023. Using a hosted database through its API does not require visiting its repository. We found the same gap in Supabase's GitHub history. Stars count the accounts that starred the repository. They do not count the people who use the hosted product without ever opening it.

How we measured this

• Commits, README text and releases come from the repository itself on GitHub: commit counts on the default branch per calendar year, the README as it stood at the end of each half year, and the published releases.
• Stars come from GitHub's star history for the repository, counted by the day each star was given, from October 2022 to 16 October 2026. It counts the stars the repository has today, so a star that was later removed is not counted.
• People on pull requests is the number of distinct accounts, excluding bots, that opened or merged a pull request in a month, from GitHub's pull request records. It is not a count of employees or of everyone who contributed code.
• Language share is GitHub's count of bytes by language on 16 October 2026.
• Funding comes from Chroma's own announcement, with the valuation from Business Insider, linked where each is mentioned.

The README history and commit counts were produced by Vela's repository briefs, which read a public repository's history and cite each claim to the record it came from.