Does Zstandard compress/decompress has backward compatibility?

[johnlanni]

Does low version compressed content can be decompressed by high version ?
Does high version compressed content can be decompressed by low version ?

[terrelln]

zstd's format is stable, starting at version 0.8.1. All zstd versions >= 0.8 are forwards and backwards compatible.

zstd has legacy support, enabled by default, that can decode the data produced by zstd versions down to 0.4.0. However very old zstd decompressors, with version < 0.8, cannot decode the stable zstd format.