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+# Promptkit v0.21.0
+
+This minor release updates ConfigKit from v1.1.0 to v1.2.0, making main-relative
+companion imports available through Promptkit's existing configuration-source
+API. The Go consumer minimum remains 1.27.0.
+
+## Main-Relative Companion Imports
+
+Applications can bind a non-file underlay's declared imports to the selected
+main configuration's filesystem context. For example, an application can load
+prompt definitions from an adjacent `prompts/` directory without calculating
+that directory before loading the main configuration.
+
+Imports remain explicitly selected by the caller; the upgrade does not enable
+automatic discovery. Imported prompt message files retain their source-local
+context. The [consumer example](../consumers/pkg-promptkit.md#load-companion-prompts-relative-to-the-main-configuration)
+shows collection mounting and YAML filename filtering. ConfigKit's
+[layered-loading contract](https://forge.maximumdirect.net/base-layer/configkit/src/tag/v1.2.0/docs/config.md#layered-loading)
+defines context selection and fallback behavior.
+
+## Compatibility And Upgrade
+
+Promptkit's exported methods and request shapes are unchanged. No configuration
+format migration is required from v0.20.0. Applications constructing ConfigKit
+`Input` or `LayeredOptions` with positional struct literals must switch to
+field-named literals because those upstream types gained fields. See the
+[ConfigKit release notes](https://forge.maximumdirect.net/base-layer/configkit/src/tag/v1.2.0/docs/releases/v1.2.0.md)
+for upstream changes.
+
+```sh
+go get go.maximumdirect.net/promptkit@v0.21.0
+```
+
+[COPYRIGHT](https://forge.maximumdirect.net/base-layer/promptkit/src/tag/v0.21.0/COPYRIGHT) | [LICENSE](https://forge.maximumdirect.net/base-layer/promptkit/src/tag/v0.21.0/LICENSE) | [ATTRIBUTION](https://forge.maximumdirect.net/base-layer/promptkit/src/tag/v0.21.0/docs/oss/attribution.md)