1. install it (bun i -g fix-bun)
2. run it in any project (bunx fix-bun)
3. profit

you can also specify paths by putting a bun.lock file in the arguments. you can also add a --silent/-S argument to make the command silent.

this pertains to the bun issue #20395 that i opened. as i explained to them, trailing commas are not part of the specification (while it rather says not to do it). furthermore, this destroys compatibility when you just need to JSON.parse the lockfile. importing the lockfile requires it to exist or requires that you add asynchronous code, which does not work well in some environments. on the other hand, requiring it destroys node.js compatibility (which is still critical because bun is missing key features).