Git 3.0 plans to switch its default hashing algorithm from SHA-1 to SHA-256 to address theoretical collision vulnerabilities, but the author argues this breaking change will impose significant costs on users for minimal practical benefit, as SHA-1 collisions have never occurred in billions of real repositories despite being mathematically possible.
PolyXOR128 is a 128-bit universal hash function designed for fast file and data stream integrity checks with cryptographic strength, achieving throughputs up to 130 GB/s on modern CPUs. It offers mathematically proven low collision rates but requires hardware-accelerated carryless multiplication, demands secret key management, and has not yet undergone third-party cryptanalysis.