Compatibility¶
Format version is encoded in the MSZ header at bytes 4–11
(version_major.version_minor). The current format is 1.0.
| Library version | MSZ format | MSZX manifest | Notes |
|---|---|---|---|
| 1.0.x | 1.0 | 1 | Current stable |
Stability promises¶
- MSZ format 1.0 — frozen. Existing MSZ files will be readable by all future 1.x releases.
- MSZX manifest schema — additive only. New optional fields can be added, but existing fields will keep their names and meanings.
- Algorithm IDs — frozen. An MSZ file written with
delta32(_delta32_transform_ = 4700006) will always be decompressible with the same ID. Experimental algorithms (currentlyvdelta16,vdelta24) are the exception — see vdelta.
Version bump policy¶
A new MSZ format major version means existing files cannot be read. The
project will avoid this unless absolutely necessary; in practice it would
likely come with a one-time mscompress migrate tool.