At Grab, our decade-old Go monorepo had become a 214GB monster with 13 million commits, causing 4-minute replication delays and crippling developer productivity. Through custom migration tooling and strategic history pruning, we achieved a 99.9% reduction in commits while preserving all critical functionality. The result? 36% faster clones, eliminated single points of failure, and a 99.4% improvement in replication performance—transforming our biggest infrastructure bottleneck into a develo...