From Maintainer Aaron Poffenberger <akp at hypernote dot com>
kCalDAV is a simple, safe, and minimal CalDAV server depending only on
kcgi(3), SQLite, and expat(3). The ISO C source code is ISC licensed.
For the time being, it works only for simple setups, for example, a
calendar collection shared between Mozilla Lightning, Mac OS X iCal,
and iOS7 (iPhone4) clients.