LZ4 (compress/lz4)

Ultra-fast lossless compression with best-in-class speed. LZ4 is the go-to algorithm when decompression speed matters more than compression ratio—ideal for real-time streaming, game assets, and in-memory caching.

Usage

import { compress, decompress, maxCompressedSize } from "compress/lz4";
import { alloc, free } from "mem";

let data = "Hello, Vex compression!";
let ptr = data.as_ptr() as *void;
let len = data.len() as i64;

// Compress
let outCap = maxCompressedSize(len);
let comp = alloc(outCap as u64);
let compLen = compress(ptr, len, comp, outCap);

// Decompress
let decomp = alloc(len as u64);
let decompLen = decompress(comp, compLen, decomp, len);

free(comp);
free(decomp);

API

Function	Description
compress(src, srcLen, dst, dstCap): i64	Compress data into LZ4 block format
decompress(src, srcLen, dst, dstCap): i64	Decompress LZ4 block
maxCompressedSize(srcLen): i64	Max output buffer size for allocation

Implementation

LZ4 uses a hash table for matching. The Vex implementation fits in ~350 lines vs ~2,000 lines in C, while remaining fully optimizable by the LLVM backend.