Not a fork, but a new project that takes a subset of the old Bun code to create something new, meant to complement Bun.
“Cruller is not intended to replace Bun for development. It is a minimal, specialized runtime for executing production code. In any case, I do not want to throw away such a large codebase that has taken several years to build. It makes more sense to turn it into a convenient embeddable library that can be used throughout the Zig ecosystem.”
The git history should have been retained. It's helpful for the files that came over.
There is no good reason to erase all of the history. They should have deleted the files they didn't want to keep in a new commit.
Similarly, a "fork" as we understand it in the context of software is this thing that, even though it's a modified copy, retains its extrinsic identity: "This software X was worked on in Y context, and is now being worked on in Z+ contexts". Same software, even if it gets a name change.