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+# Sources
+
+This directory contains some OpenAPI definitions included in this project
+solely for the purpose of testing various progenitor features. Some of these
+have been pulled in from other projects:
+
+- `api.github.com.json`: https://github.com/github/rest-api-description
+- `buildomat.json`: https://github.com/oxidecomputer/buildomat
+- `keeper.json`: https://github.com/jclulow/keeper
+- `nexus.json`: https://github.com/oxidecomputer/omicron
+- `propolis-server.json`: https://github.com/oxidecomputer/propolis
+
+Note that keeper and buildomat have diverged in order to validate support for various features. The others should not be changed other than updating them from their source repository.
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