What does a chart's .helmignore file exclude, and when does it have no effect?

### What it is for A chart directory in a working tree usually holds more than a chart: a `.git` directory, editor droppings, CI config, a `Makefile`, test fixtures, screenshots, sometimes a local `values-dev.yaml` with a real password in it. `helm package` would otherwise sweep all of that into the artifact you hand to other people. `.helmignore` is the filter that decides what a chart *is* when Helm reads it off disk. `helm create` scaffolds one covering version-control and editor noise, and most teams extend it. ### Syntax One pattern per line. Blank lines and lines beginning with `#` are ignored. Patterns are Unix shell globs, matched against paths relative to the chart root: - A pattern with no slash matches by base name at any depth: `*.bak` drops backups wherever they sit. - A pattern containing a slash is anchored relative to the chart root: `ci/reports` matches only that path. - A trailing slash restricts the match to directories: `tests/` excludes the directory, not a file called `tests`. - A leading `!` negates an earlier pattern, re-including something a broader rule had matched. The negation rule has a sharp edge. Helm prunes an excluded directory rather than descending into it, so once `fixtures/` is excluded, `!fixtures/keep-me.pdf` does not resurrect that file — Helm never looked inside. If you need one file out of a large directory, exclude the contents narrowly (`fixtures/*.pdf`) instead of the directory itself. ### When the rules apply — and when they are irrelevant The rules run when Helm **loads a chart from a directory**. That is `helm package`, and it is equally `helm install ./pdfsign`, `helm upgrade ./pdfsign`, `helm template ./pdfsign` and `helm lint ./pdfsign` — installing straight from a source directory is subject to exactly the same filter as packaging. They are irrelevant to an archive. A `.tgz` is a snapshot of the decision that was already made; Helm loading `pdfsign-2.7.3.tgz` reads whatever is in it. This is the point candidates most often get wrong, and it has a concrete operational shape. Suppose the chart for a PDF-signing service carries a `fixtures/` directory of 41 sample documents, about 18 MB, and nobody noticed until `pdfsign-2.7.3.tgz` was already published. Adding `fixtures/` to `.helmignore` fixes every future build; version 2.7.3 stays 18 MB forever. The remedy is a new chart version, 2.7.4, packaged with the corrected rules — not an edit to a published artifact. The same reasoning applies with more force to a secret. If a values file with a real credential was packaged into a published archive, adding an ignore rule afterwards is not remediation: the credential shipped, it is in whatever repository or registry holds that archive, and it must be rotated. ### Second-order effect: the chart's file set Helm builds an in-memory chart from the files the loader collected, so anything `.helmignore` excluded is simply not part of the chart. If a template reads a file from the chart's own contents, ignoring that file makes the render fail or silently produce nothing, and the failure only appears when someone installs from a packaged copy. When a chart deliberately embeds an asset — a default policy document, a config fragment — make sure no broad pattern (`*.json`, `docs/`) is quietly eating it. The reverse mistake is over-broad exclusion of things Helm needs. A blanket pattern that matches archives or subdirectories can strip vendored dependencies out of `charts/`, producing a package that installs fine on your laptop (where `charts/` is populated) and fails for everyone else. Keep patterns specific, and verify by inspecting the artifact rather than trusting the rules. ### Verifying The honest check is to look at what you built: list the archive's contents, or extract it into a temporary directory and compare. Size is a decent smoke signal — a chart that suddenly grows by an order of magnitude has picked up something it should not have. In CI it is cheap to assert that the packaged archive contains no path matching a deny list, which catches the class of mistake before publication rather than after. ### What it is not `.helmignore` is not security. It is not `.gitignore` (a file can be committed and still excluded from the chart, or vice versa — they are independent lists), it is not a values filter, and it does not stop anything a template renders from reaching the cluster. It only decides which files on disk become part of the chart Helm loads.