But the FAQ says:
Is there a developer API? Not yet. Once we reach General Availability for WebContainer we plan to release an API surface.
Is this open source? Today no, but the API will be open source to developers at GA.
The closest I can find from Stackblitz is this Github issue where the Stackblitz founder 4 years ago responds to "By any chance, are you open-sourcing the codebase?" with:
Definitely! We're planning on open sourcing the core tech behind stackblitz (which is what this repo is for), but there's a lot that needs to happen between now & then. I'm going to fill out the readme a bit which should answer this in detail — will circle back shortly.
https://github.com/stackblitz/core/issues/28#issuecomment-32...
To what extent is the Stackblitz or even underlying WebContainer tech open source / documented?