atmos helm diff

Show a real unified diff between the chart Atmos would render and a baseline — the currently deployed release, a local manifest file, or the manifests in your GitOps deployment repository. The chart is rendered client-side with the Helm Go SDK and compared with the helm-diff engine, so changes read as familiar +/- lines. Secret values are redacted.

Usage

atmos helm diff <component> --stack <stack> [options]

# Diff against the deployed release (requires cluster access).
atmos helm diff monitoring -s plat-ue2-dev

# Diff against a local baseline manifest (offline, no cluster).
atmos helm diff monitoring -s plat-ue2-dev --from-manifest=current.yaml

# Diff against the GitOps deployment repository (offline, git access only).
atmos helm diff monitoring -s plat-ue2-dev --against=target

# Preview an apply with transient Helm values.
atmos helm diff monitoring -s plat-ue2-dev -f incident-values.yaml --set image.tag=2026.09.09

# Diff all components tagged "production" (composes with --all/--affected)
atmos helm diff --all --tags production

Baselines

diff compares the freshly rendered chart against one baseline, selected by flag precedence (--from-manifest → --against → deployed release):

Deployed release (default)

The manifest of the currently installed release, read from the cluster. A release that does not exist yet shows every object as added. This is the only mode that needs cluster access.

--from-manifest=<path>

A local baseline manifest file. Fully offline — no cluster, no git.

--against=target[:<name>]

The manifests currently published in a non-cluster provision target (e.g. a git deployment repository). Reads the target's current state and diffs against it — the producer side of a GitOps workflow. Offline (git access only). Without :<name> the provision.default target is used.

Flags

--stack, -s (required)

Atmos stack.

--against=<source> (optional)

Baseline to diff against: release (the deployed release, default) or target[:<name>] for a git deployment-repo provision target.

--from-manifest=<path> (optional)

Diff against a local baseline manifest file instead of the cluster (offline).

--context=<n> (optional)

Number of unchanged context lines shown around each change. Defaults to 3.

--dependency-update (optional)

Fetch declared chart dependencies when they are missing. This may access dependency repositories and update the chart's charts/ directory and lock file.

-f / --values, --set, --set-string, --set-file, --set-json, --set-literal (optional)

Repeatable Helm-compatible value overrides for this preview. Reuse them with apply to preview the exact deployment; they do not modify stack configuration. See runtime value overrides.

--all / --affected / --include-dependents (optional)

Process multiple Helm components in dependency order.

--tags / --labels (optional)

Filter by tags (comma-separated, matches any) or labels (comma-separated key=value or key:value pairs within one occurrence, and/or repeated for more, matches all): --tags=production,tier-1, --labels=cost-center=platform or --labels cost-center=platform --labels compliance=sox. Compose with --all/--affected to narrow the selected set further; cannot be combined with a single component argument.

note

atmos helm plan is an alias for diff. To render the chart without comparing, use atmos helm template. The diff uses the helm-diff library directly — you do not need to install the helm-diff CLI plugin.