The official Isabelle2022 release is scheduled for late October 2022. This blog entry is dynamically updated to follow the sequence of public release candidates. See also the isabelle-release repository.

• Isabelle2022-RC0 (08-Aug-2022): informal snapshot for experimentation, approx. 4 weeks before regular RC1.

• Isabelle2022-RC1 (11-Sep-2022): first official release candidate, approx. 6 weeks before final lift-off. Almost everything is ready for testing. See also AFP/34a31d29f666.
  • There is presently no heap image for Isabelle/HOL on Windows, macOS/ARM, Linux/ARM; the adhoc build requires a few minutes after application startup.

• Isabelle2022-RC2 (18-Sep-2022): consolidated release candidate with notable updates. See also AFP/59b24f0e98b1.
  • Proper heaps for Isabelle/HOL on all supported platforms.
  • Bundled MLton compiler for x86_linux: Ubuntu 22.04 has discontinued the former mlton package.
  • Update to Azul OpenJDK 17.0.4.1 (22-Aug-2022).
  • Update to Scala 3.2.0 (05-Sep-2022).
  • More robust SSH support in Isabelle/Scala based on OpenSSH client programs (ssh + sftp): former JSch (ssh-java) has been discontinued.
  • More robust isabelle build_docker tool, based on Ubuntu 22.04.
  • Minor tuning of HOL libraries and proofs.

• Isabelle2022-RC3 (02-Oct-2022): further consolidated release candidate and fork-point of the development repository. See also AFP/a74db29363f5.
  • Update bundled Cygwin component: include openssh (for rsync).
  • Update bundled Naproche component.
  • isabelle build -o browser_info works with partial builds.
  • Minor tuning of system options (e.g. for ssh).
  • Misc tuning of Isabelle/Scala interfaces: proper support for ssh.read_dir.
  • Last-minute tuning of HOL libraries.
  • Last-minute changes of ZF syntax.
  • More NEWS.

• * Isabelle2022-RC4 (18-Oct-2022): pre-final release candidate. See also AFP release: afp-2022.
  • Cygwin: proper home directory for ~/.ssh configuration.
  • Update bundled Naproche component.
  • Scala: Minor patches to support spaces in installation directory.
  • Poly/ML: more stable repository version, notably for ARM64.
  • Isabelle/VSCode: proper symbol encoding for auxiliary files, e.g. ML_file.
  • Headless PIDE session (e.g. via isabelle server) supports editing of files (as in Isabelle2018).
  • Proper warning for isabelle build with empty selection (as in Isabelle2019).

• Isabelle2022 (25-Oct-2022): final release candidate. See also AFP release: afp-2022.
  • Session ROOT: proper default chapter Unsorted.
  • Windows: more robust startup on national locale.
  • Implicit Java/Scala build: more accurate classpath (excluding .).
  • More public Isabelle/ML and Isabelle/Scala operations, to support Isabelle/DOF.