Module cache 

Persistent per-file compile cache at <output_dir>/.cache/dmc/, one {16-hex blake3}.json per record. Cache hits are O(read + parse). Key encodes dmc version + source bytes + path + config fingerprint; nothing overwrites in place.

Structs

FileCache

Functions

fingerprint

Empty vec on serialisation failure (cache still works, collides across non-serialisable configs).