philiprehberger-checksum

https://github.com/philiprehberger/rb-checksum

Compute MD5, SHA-256, SHA-512, and CRC32 checksums for strings and files. HMAC-SHA256 and HMAC-SHA512 with timing-safe verification. File checksums use streaming reads for constant memory usage. Supports multi-algorithm single-pass computation, multi-file hashing, and verification.