Scaling merge-ort across GitHub

This post details the adoption and implementation of Git's `merge-ort` strategy across GitHub for both merge commits and rebases. It describes the migration process, including the use of Scientist for A/B testing and `git-replay` for rebases. Performance gains are quantified, showing significant speedups (e.g., 10x at P50 for merges, substantial resource savings for rebases). The post also highlights the shift from a `libgit2`-based strategy to `merge-ort` to improve correctness and meet user expectations.