Flux

v2.8.4CI/CD & App Delivery

Apr 8, 2026

Flux v2.8.4 is a CLI-only patch fixing two bugs: Windows compatibility for 'flux build/diff ks' and source flag validation in 'create kustomization'.

enhancementWindows users: upgrade to unblock 'flux build/diff ks'
If your team uses Windows workstations or CI runners for Flux kustomization diffs, these commands were silently broken. Upgrade the CLI to v2.8.4 — the fix is CLI-side only, so no cluster-side changes are needed.
breakingCheck your 'create kustomization' scripts for invalid --source values
The '--source' flag now validates input properly. Scripts or pipelines passing malformed source references that previously slipped through will now fail explicitly. Test your automation before rolling out the updated CLI in CI/CD pipelines.

Key changes (3)

Fixed 'flux build ks' and 'flux diff ks' commands on Windows — previously broken
Fixed '--source' flag validation in 'flux create kustomization' to catch invalid inputs early
Dependency updates to fluxcd/pkg packages