The official Isabelle2026 release is scheduled for mid October 2026. This blog entry is dynamically updated to follow the sequence of public release candidates.

• Isabelle2026-RC0 (17-Aug-2026): informal snapshot for experimentation, approx. 4 weeks before regular RC1. See also AFP/3679b12d85e3.

The corresponding Mercurial repository clone is availabe via hg clone https://isabelle.sketis.net/repos/isabelle-release