My assumption is that its based on that repo but with the "ee/" folder removed, per https://github.com/PostHog/posthog#open-source-vs-paid

Presumably so folks can be sure they're not accidentally pulling in proprietary code.

From the repo's about section: PostHog FOSS is a read-only mirror of PostHog, with all proprietary code removed. NOTE: This repo is synced automatically from the main PostHog repo. Please raise any issues and PRs there.

From the repo you linked:

> This repo is available under the MIT expat license, except for the ee directory (which has its license here) if applicable.

> Need absolutely 100% FOSS? Check out our posthog-foss repository, which is purged of all proprietary code and features.

The PostHog Enterprise license (the “Enterprise License”)