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Which is why I said this in my previous comment:

> In other words: don't think of it as "meticulously grooming a commit history"; instead, think of it as your actual job not being "developer", but rather, as you (and all your coworkers) being the writers and editors of a programming textbook about the process of building program X... which happens to compile to program X.

If you have to "wade through experiments" to read the commit history, that means that the commit history hasn't had a structural editing pass applied to it.

Again: think of your job as writing and editing a textbook on the process of writing your program. As such, the commit history is an entirely mutable object — and, in fact, the product.

Your job as editor of the commit-history is, like the job of an editor of a book, to rearrange the work (through rebasing) into a "narrative" that presents each new feature or aspect of the codebase as a single, well-documented, cohesive commit or sequence of commits.

(If you've ever read a programming book that presents itself as a Socratic dialogue — e.g. Uncle Bob's The Clean Coder — each feature should get its own chapter, and each commit its own discussion and reflected code change.)

Experiments? If they don't contribute to the "narrative" of the evolution of the codebase — helping you to understand what comes later — then get rid of them. If they do contribute, then keep them: you'll want to have read about them.

Features gradually introduced over hundreds of commits? Move the commits together so that the feature happens all at once; squash commits that can't be understood without one-another into single commits; break commits that can be understood as separate "steps" into separate commits.

After factoring hunks that should have been independent out into their own commits, squashing commits with their revert-commits, etc., your commit history, concatenated into a file, should literally be a readable literate-programming metaprogram that you read as a textbook, that when executed, generates your codebase. While also still serving as a commit history!

(Keeping in mind that you still have all the other things living immutably in your SCM — dead experiments in feature branches; a develop branch that immutably reflects the order things were merged in; etc. It's only the main branch that is groomed in this fashion. But this groomed main branch is also the base for new development branches. Which works because nobody is `git merge`ing to main. Like LKML, the output-artifact of a development branch should be a hand-groomed patchset.)

And, like I said, this is all strictly inferior to an approach that actually involves literate programming of a metaprogram of codebase migrations — because, by using git commit-history in this way, you're gaining a narrative view of your codebase, but you're losing the ability to use git commits to track the "process of editing the history of the process of developing the program." Whereas, if you are actually committing the narrative as the content of the commits, then the "process of editing the history" is tracked in the regular git commits of the repo — which themselves require no grooming for presentation.

But "literate programming of a metaprogram that generates the final codebase" can only work if you have editor support for live-generating+viewing the final codebase side-by-side with your edits to the metaprogram. Otherwise it's an impenetrably-thick layer of indirection — the same reason Aspect-Oriented Programming never took off as a paradigm. Whereas "grooming your commit history into a textbook" doesn't require any tooling that doesn't already exist, and can be done today, by any project willing to adopt contribution policies to make it tenable.

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Or, to put this all another way:

Imagine there is an existing codebase in an SCM, and you're a technical writer trying to tell the story of the development of that codebase in textbook form.

Being technically-minded, you'd create a new git repo for the source code of your textbook — and then begin wading through the messy, un-groomed commit history of the original codebase, to refactor that "narrative" into one that can be clearly presented in textbook form. Your work on each chapter would become commits into your book's repo. When you find a new part of the story you want to tell, across several chapters, you'd make a feature branch in your book's repo to experiment with modifying the chapters to weave in mentions of this side-story. Etc.

Presuming you finish writing this textbook, and publish it, anyone being onboarded to the codebase itself would then be well-advised to first read your textbook, rather than trying to first read the codebase itself. (They wouldn't need to ever see the git history of your textbook, though; that's inside-baseball to them, only relevant to you and any co-editors.)

Now imagine that "writing the textbook that should be read to understand the code in place of reading the code itself" is part of the job of developing the program; that the same SCM repo is used to store both the codebase and this textbook; and that, in fact, the same textual content has to be developed by the same people under the constraints of solving both problems in a DRY fashion. How would you do it?