Restic 0.19.0: new features

Restic 0.19.0 released on 9 June 2026: new features.

This version brings numerous optimisations: new compression modes, reduced memory footprint, faster index loading. But two fixes in particular have caught our attention on the Windows side, as they relate to restore fidelity and the completeness of Windows backups.

Restic, the backup engine at the heart of Cybee

Cybee is built on Restic, a recognised and tried-and-tested open-source backup engine. This choice shapes our approach: auditable and transparent code, publicly traceable fixes, and an active community that continuously drives the tool forward. It is also a cornerstone of our sovereign positioning: trust is built on transparency, not on a ‘black box’.

Keeping a close eye on Restic releases is therefore part of our continuous improvement process. Version 0.19.0 is a good example of this.

Restic 0.19.0 at a glance

Notable changes in this release include:

New zstd compression modes (fastes and better) for finer control over the speed/compression ratio trade-off.
Significantly faster index loading on large repositories; the mount command now loads indexes on demand.
Reduced memory usage for check, copy, diff and stats on large snapshots.
Restoration of file ownership by username and group on UNIX (ownership-by-name).
And two Windows fixes, which we detail below.

Focus No. 1 : Restoring ACL inheritance on Windows

Since Restic 0.17.0, backing up Windows security descriptors has been supported. These descriptors contain the ACLs, the list of permissions that determines who is allowed to do what on a file or folder.

Until now, the inheritance status of Access Control Entries (ACEs) was not restored correctly. Specifically, a permission inherited from a parent folder (where IsInherited = True) was restored as an explicit permission (IsInherited = False). On the surface, the permissions appeared identical. In reality, their structure had changed.