Owned temp directory, force-removed on drop (store outputs are read-only until made writable).

Basename -> idx index for the lookups during root finding and the unknown-on-disk scan. Borrows from the StoreGraph; built once.

One iteration's throwaway store and tool invocations.

Running GC roots socket server. Dropping it tears down the listener, removes the socket file, and joins the accept thread.

Liveness state shared between the deletion loop and the socket server. Roots from clients can only flip dead -> protected; `pending` tracks in-flight

Input decoded into in-range node indices.

Handle to the Nix store SQLite database.

Lock held while mutating a profile's generations, interoperable with Nix's PathLocks protocol (pathlocks.cc): flock(2) on "<profile>.lock", stale dete

In-memory snapshot of the store reference graph in CSR layout.