Cross-reference glossary for README.adoc, EXPLAINME.adoc, and the JanusKey wiki.
- Inversion metadata
-
The metadata attached to every JanusKey operation, containing sufficient information to reverse that operation. Delete stores content; modify stores original hash; move stores original path; copy stores destination path. Classification: project-specific (packaging).
- Reversibility guarantee
-
The claim that no JanusKey operation (except
shred) destroys the information required for inversion. Currently an engineering guarantee (implemented in Rust), not a formal theorem (mechanically verified proof pending). Classification: project-specific (claim).
- Maximal Principle Reduction (MPR)
-
A security methodology where vulnerability elimination occurs by construction rather than verification. In JanusKey: the irreversible-deletion vulnerability is eliminated because no such code path exists (except
shred). Project-specific vocabulary for the standard principle "secure by construction." Classification: project-specific (vocabulary).
- Content-addressed storage (CAS)
-
Storage indexed by SHA-256 hash of content. Provides deduplication and content integrity. Standard in Git, IPFS, Nix. Classification: standard.
- Append-only log
-
The metadata store recording the sequence of JanusKey operations. Never mutated in place; new operations are appended. Enables history traversal and rollback. Classification: standard (event sourcing).
- Transaction manager
-
Groups operations into atomic units with commit/rollback semantics. If any operation in a transaction fails, the entire transaction rolls back. Classification: standard.
- Secure obliteration (
jk shred) -
The deliberate exception to reversibility. Attempts overwrite-in-place to destroy file contents. Best-effort only: cannot guarantee physical erasure on SSD (wear leveling), CoW (ZFS, Btrfs), or journaling filesystems. Physical destruction is the only guaranteed obliteration on modern media. Classification: project-specific (operation).