  We present an integration of a safe C dialect, Checked C, for the Internet of
Things operating system RIOT. We utilize this integration to convert parts of
the RIOT network stack to Checked C, thereby achieving spatial memory safety in
these code parts. Similar to prior research done on IoT operating systems and
safe C dialects, our integration of Checked C remains entirely optional, i.e.
compilation with a standard C compiler not supporting the Checked C language
extension is still possible. We believe this to be the first proposed
integration of a safe C dialect for the RIOT operating system. We present an
incremental process for converting RIOT modules to Checked C, evaluate the
overhead introduced by the conversions, and discuss our general experience with
utilizing Checked C in the Internet of Things domain.
