Eschewed features

• This issue is not requesting templating, unstuctured edits, build-time side-effects from args or env vars, or any other eschewed feature.

What would you like to have added?

Support for referencing configurations files located in parent directories of a kustomization.yaml.

Currently, Kustomize prevents loading files outside from parent directories (including via symlinks pointing to parent folders). This makes it difficult to share common configuration files (e.g., transformers or nameReference configs) across multiple kustomizations in a repository.

configurations:
  - ../kustomizeconfig.yaml

Why is this needed?

In real-world projects, it is common to have multiple overlays or components that need to reuse the same configurations.

Today, because Kustomize blocks access to parent directories:

• We cannot centralize shared configuration
• We are forced to duplicate configuration files across multiple directories
• This leads to maintenance issues and risk of configuration drift

This limitation is particularly painful in monorepos or structured environments where DRY principles are important.

Can you accomplish the motivating task without this feature, and if so, how?

Yes, but only with suboptimal workarounds:

• Copy-pasting the configuration files into each kustomization (not maintainable)
• Using hardlinks (not portable and not preserved well by Git)

What other solutions have you considered?

• External tooling to copy files during CI

Anything else we should know?

No response

Feature ownership

• I am interested in contributing this feature myself! 🎉