sem

https://github.com/Ataraxy-Labs/sem stores AST operations in git https://news.ycombinator.com/item?id=47294924

Git line diffs are 40 years old. they still can't tell the difference between "renamed a variable" and "rewrote the logic." your diff tool doesn't understand your code, it never did. we fixed that, introducing Semantic diffs! Fully deterministic, no llm calls Powered by https://github.com/ataraxy-labs/sem

Great point. C/C++ with macros and preprocessor directives is where tree-sitter's error recovery gets stretched. We support both C and C++ in sem-core(https://github.com/Ataraxy-Labs/sem) but the entity extraction is best-effort for heavily macro'd code. For most application-level C++ it works well, but something like the Linux kernel would be rough. Honestly that's an argument for gritzko's AST-native storage approach where the parser can be more tightly integrated.

We got asked this on the X thread too, when we went viral here https://x.com/rs545837/status/2021020365376671820. Your git doesn't change at all. Weave plugs in through git's merge driver interface (.gitattributes), so git still handles everything, it just calls weave for the content merge step instead of its default line-level algorithm. All your git commands, workflow, and history stay exactly the same. For diffing arbitrary files outside git, we built sem (https://github.com/ataraxy-labs/sem) which does entity-level diffs. sem diff file1.py file2.py shows you which functions changed, were added, or deleted rather than line-level changes

This is the right question. Storing ASTs directly would make all of this native instead of layered on top. The pragmatic reason weave works at the git layer: adoption. Getting people to switch merge drivers is hard enough, getting them to switch VCS is nearly impossible. So weave parses the three file versions on the fly during merge, extracts entities, resolves per-entity, and writes back a normal file that git stores as a blob. You get entity-level merging without anyone changing their workflow. But you're pointing at the ceiling of that approach. A VCS that stores ASTs natively could answer "did any concurrent branches touch this function?" as a query, not as a computation. That's a fundamentally different capability. Beagle looks interesting, will dig into the BASON format. We built something adjacent with sem (https://github.com/atar