Package cache implements a cache.

Package dnstest allows for easy testing of DNS client against a test server.

Package dnsutil contains DNS related helper functions.

Package edns provides function useful for adding/inspecting OPT records to/in messages.

Package fall handles the fallthrough logic used in plugins that support it.

Package fuzz contains functions that enable fuzzing of plugins.

Package log implements a small wrapper around the std lib log package.

Package nonwriter implements a dns.ResponseWriter that never writes, but captures the dns.Msg being written.

Package parse contains functions that can be used in the setup code for plugins.

Package singleflight provides a duplicate function call suppression mechanism.

Package uniq keeps track of "thing" that are either "todo" or "done".

Package up is used to run a function for some duration.

Package upstream abstracts a upstream lookups so that plugins can handle them in an unified way.