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+The crater subdirectory is where badly broken modules go until the complete
+removal can be done. The reasons to move a module there can include:
+  - The source archive is nowhere to be found on the internet;
+  - The source code doesn't compile anymore or is broken due to deprecations
+    and there's no maintenance done upstream;
+  - The module has been replaced by a new one.
+
+Complete removal will be made once no problems have been reported for a good
+while and that most modules have been tested to work well without it.