Blockchain Commons LifeHash for TypeScript

Disclaimer: This package is under active development and APIs may change.

Introduction

LifeHash is a method of generating visual hashes from data. It is based on Conway's Game of Life cellular automaton. Given the same input, LifeHash will always produce the same visual output, making it useful for verifying data integrity at a glance.

LifeHash generates a unique, colorful, abstract image from any input data. It's designed to be:

• Deterministic: Same input always produces the same image
• Visually Distinct: Different inputs produce visually different images
• Human-Friendly: Easy to recognize and compare at a glance
• Collision-Resistant: Hard to find two inputs that produce similar images

C++ Reference Implementation

This TypeScript implementation is based on bc-lifehash (commit 0444dbe). Test parity is enforced against the 35 upstream test vectors vendored at tests/fixtures/test-vectors.json.

Rust parity fuzz

tests/parity.test.ts runs ~1000 deterministic fuzz inputs through the TS port and compares each rendered image's SHA-256 against a pre-computed value produced by bc-lifehash (Rust). The golden file lives at tests/fixtures/golden.json.

To regenerate after a meaningful change to the Rust crate:

cd /path/to/bc-lifehash-rust
cargo run --release --example golden > /path/to/typescript/packages/lifehash/tests/fixtures/golden.json

The generator (examples/golden.rs) uses a fixed-seed LCG, so re-running it always produces an identical file (verifiable with diff -q).