lmdb missing from the documentation
According to "make info" against today's git HEAD, lmdb is mandatory:
Dependencies
------------
[yes] libknot (lib)
[no] lmdb (lib)
[yes] luajit (daemon)
[yes] libuv (daemon)
[yes] libgnutls (daemon)
[yes] nettle (DNS cookies)
But it is not listed in the packages at https://knot-resolver.readthedocs.io/en/latest/build.html