Fully in-browser container builds

You can't use RUN in my demo, no... but you would be surprised at how much you can do with "just download & assemble things" ;)

For instance, if you install packages using pip or a conda tool like pixi, you don't actually need RUN. You can assemble the layers yourself, in code you control, applying tricks that bring down container build time from minutes to seconds.

Yeah, just embedding the entry point