This looks really cool. Congratulations on the milestone.

Does the elixir->js compiler exist as a separate project, or is it built into the framework? Is it based on an existing transpiler? How does it compare / contrast to something like gleam (which, AFAIU also let's you transpile elixir to JS)?

I may be wrong but I believe the elixir->js compiler is currently built into the framework but it could potentially be separated in the future.

Gleam is different in that JS is a first-class target and built into Gleam's compiler, while Hologram is a standalone project.