OpenXiv: a preprint server that lives in your social feed

OpenXiv is a single-instance preprint server built on the AT Protocol. Each accepted preprint is stored as an app.openxiv.paper record in the author's own Personal Data Server (PDS), with the OpenXiv instance acting as an App View that indexes records but does not own them. New preprints federate to Bluesky as app.bsky.feed.post entries so abstracts appear in researchers' regular social feeds. The catalogue exposes an OAI-PMH 2.0 endpoint validated by BASE OVAL and indexed by BASE and CORE. ISSN 3120-9556 was issued by the Lithuanian National Library on 18 May 2026, the launch date. The catalogue is represented as Wikidata item Q139860032. Every preprint carries a structured AI disclosure (none, assistant, coauthor, primary) and three labelled explainer tiers (school, undergrad, expert) so readers outside the subfield can pick their level. Unverified work returns for revision with a published refusal packet that names the failure mode, rather than triggering author bans. Source code is AGPL-3.0-or-later at github.com/davidichalfyorov-wq/openxiv. Crossref DOI minting via Sponsored Membership is in progress.