Linux kernel
The original version of Squashfs used gzip compression, although Linux kernel 2.6.34 added support for LZMA and LZO compression, Linux kernel 2.6.38 added support for LZMA2 compression (which is used by xz), Linux kernel 3.19 added support for LZ4 compression, and Linux kernel 4.14 added support for Zstandard compression.