The basic approach is Myers' diff algorithm. Both bytewise diffing and utf-8 aware diffing are supported.
This project should be considered alpha quality, the test suite isn't particularly exhaustive and there are a number of improvements to be made for more readable diffs. The public API will change.
The diff-match-patch library and dissimilar implement semantic cleanups for more human-friendly, readable diffs. This is something we will implement in this library, but we don't have it yet.
This project is developed and tested on Zig 0.9.