It's always the first step. The second step would be switching the license and only supporting the changed licensed version, then "donating" the unmaintained version to the community.

It's not true, in that sense. Commits in jj are basically the same as commits in git as far as mutability is concerned. But in jj you normally work with changes, rather than commits, and open changes are mutable (by altering which immutable commit they point to in the backing store). And there is effectively an append-only audit trail of these alterations (which is what makes `jj undo`/`jj redo` simple).

Some comments here are confusing the issue by saying ‘commit’ when they mean ‘change’ in the jj sense.

Re the grandparent comment, `jj describe` provides a change description, analogous to `git commit --amend --edit` in git terms.

it is true. some history is marked immutable by default; in git, everything is mutable by default and you have to add branch protection on the server side. (granted, you can change what is immutable in jj relatively easily, so you shouldn't ignore branch protection if you're using jj exclusively with a git repo, either.)

By default, if you push to main/master, it marks those commits as immutable (you can still force change). You can configure this to other branches.

But ... is it really that different from git? You can always rewrite history in git, correct?

I feel like a lot of this is an "elephant memory" problem, too. ("An elephant never forgets.") Git was built very quickly and its early CLI was intentionally rough. Git was originally built with the idea that it was going to be all "plumbing" and to leave the good UX decisions to whatever "porcelain" people wanted to use on top, with some even expecting that there might be multiple competing "official" "porcelain" CLIs. Eventually that debate got settled in the surprise way to some of the earlier decisions about git being plumbing-first in that eventually git picked up both the "plumbing" and the official "porcelain".

There's a lot of arguments that still seem to think of the git CLI before a lot of the porcelain projects started merging into git upstream. There's a lot of people that mostly only learned the plumbing tools and don't care for the porcelain projects. It certainly doesn't help that much of the best porcelain still isn't the default experience. You have to remember `git rebase -i` for the best porcelain rebase experience. You have to remember `git add -p` for the best porcelain add experience. (This article even indirectly hints at the silliness that the best interactive `git add` is `-p` for "pinteractive" because `-i` "interactive" was already taken by a weaker one.)

That said, a lot of the porcelain is there today to take advantage of. Git has improved significantly from its plumbing-first worst CLIs. `git checkout` finally got split into `git switch` and `git restore` and both of those are great. (And no longer marked "experimental", they are official daily-use approved porcelain now.)

That's also sort of the highlight of this post that a lot of the porcelain continues to improve. The UX of the git CLI isn't etched in stone. New, better commands are possible, and indeed are getting built by smart people, some of who even care about UX for themselves and their fellow developers. Git is no longer the rush project it once was. Git no longer sees itself as "plumbing-first" at the expense of the "porcelain".

It will just maybe take a while for more of the elephants to forget the past horror stories and befuddlement.