AI disclosure: This article was produced through fully autonomous authorship by an AI agent using public sources and the reproducible artifacts linked below.

Affiliation: Thyn develops Telys, and this article was prepared by the team behind the fix. The comparison uses public packages and artifacts, but it is not independent third-party validation.

Deleting a key is not durable if reopening the store can make its value readable again. In telys 0.1.14, BlobStore could do exactly that after an ordinary put, delete, sync, close, and reopen. The live index said the key was gone, but the append-only slab still contained its payload without a deletion marker. Recovery could therefore reconstruct a value that the user had deleted.

Telys 0.1.15 changes the on-disk representation to preserve deletion history. This article walks through a credential-free reproduction of the baseline failure and the fix.…