Release notes · September 26, 2026

Megastructure Arc 2.0.1

Arc 2.0.1 keeps your current version installed if you cancel a manual upgrade on Windows, and brings back the Start menu shortcut that the update to 1.9.9 could remove.

Previous release

Safer Windows upgrades

Windows 10/11 (64-bit), or macOS 11+ on Apple Silicon. Bundled Local AI requires macOS 26+. Computer use requires macOS 14+.

Fixes and refinements

  • Windows: running the installer over an older version now pre-selects “Do not uninstall” and installs over it, as the in-app update does, so cancelling leaves your current version working. Uninstalling first is still one click away.
  • Windows: the Start menu shortcut that the in-app update to 1.9.9 could remove comes back once with the next update. If you delete it after that, it stays deleted.

System requirements

Windows 10/11 (64-bit), or macOS 11+ on Apple Silicon. Bundled Local AI requires macOS 26+. Computer use requires macOS 14+.

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