Crypta
A fingerprint for any data.
What it is
Crypta is a hands-on SHA-256 explorer that turns any input into a fixed-size hash and visualises how a single bit flip cascades through the output. The signature technique is a from-scratch implementation of the full algorithm - padding, the message schedule, and all 64 compression rounds - paired with an avalanche heatmap and a proof-of-work miner, cross-checked byte-for-byte against Node's crypto across every padding boundary. It is a dependency-light build you can download and run locally.
A from-scratch SHA-256 (padding, message schedule, 64 compression rounds) with an avalanche heatmap and a proof-of-work miner. 9 tests, cross-checked byte-for-byte against Node's crypto across all padding boundaries.
What's inside
The full source, the tests, and CI. Open it, read it, change it. A zero-dependency core, free, in the MIT spirit.
Run it after unzip
pnpm install && pnpm dev