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+<!--
+A new scriv changelog fragment.
+
+Uncomment the section that is right (remove the HTML comment wrapper).
+-->
+
+<!--
+### Patch
+
+- A bullet item for the Patch category.
+
+-->
+<!--
+### Non-Breaking
+
+- A bullet item for the Non-Breaking category.
+
+-->
+
+### Breaking
+
+- Make the type of `Nary.inject` more precise.
+  The old type involves oracular data, so any required changes downstream are almost certainly limited to testing code.
+  (I'm therefore tempted to list this as Patch instead --- violating the [PVP](https://pvp.haskell.org/) --- but the risk-reward seems prohibitive.)