 Because of the way that FSE carries over state between symbols, decompression involves processing symbols within the Sequences section of each block in reverse order (from last to first).The Linux kernel has included Zstandard since November 2017 (version 4.14) as a compression method for the btrfs and squashfs filesystems.In 2017, Allan Jude integrated Zstandard into the FreeBSD kernel and used it to create a proof of concept OpenZFS compression method.