I am trying a ./configure --with-experimental-modules This stage completes successfully, but when I do 'make' it dies because it tries to build rlm_rediswho, even though hiredis.h is missing. ./configure did detect this correctly for rlm_redis, and set targetname to empty in the Makefile: === configuring in ./src/modules/rlm_redis (/u/home/brian/git/freeradius-server/./src/modules/rlm_redis) configure: running /bin/bash ./configure '--prefix=/usr/local' '--with-experimental-modules' '--enable-ltdl-install' --cache-file=/dev/null --srcdir=. checking for gcc... gcc checking for C compiler default output file name... a.out checking whether the C compiler works... yes checking whether we are cross compiling... no checking for suffix of executables... checking for suffix of object files... o checking whether we are using the GNU C compiler... yes checking whether gcc accepts -g... yes checking for gcc option to accept ISO C89... none needed checking for redisConnect in -lhiredis... no configure: WARNING: hiredis libraries not found. Use --with-redis-lib-dir=<path>. checking for hiredis.h... no configure: WARNING: hiredis headers not found. Use --with-redis-include-dir=<path>. configure: WARNING: silently not building rlm_redis. configure: WARNING: FAILURE: rlm_redis requires: libhiredis hiredis.h. configure: creating ./config.status config.status: creating Makefile But it didn't for rlm_rediswho: === configuring in ./src/modules/rlm_rediswho (/u/home/brian/git/freeradius-server/./src/modules/rlm_rediswho) configure: running /bin/bash ./configure '--prefix=/usr/local' '--with-experimental-modules' '--enable-ltdl-install' --cache-file=/dev/null --srcdir=. configure: creating ./config.status config.status: creating Makefile So I think the configure.in in rlm_rediswho needs expanding somehow. Whilst rlm_rediswho doesn't directly use hiredis.h, it does #include <rlm_redis.h> and that file has #include <hiredis/hiredis.h> I'm not sure of the best solution, short of duplicating the configure logic between rlm_redis and rlm_rediswho. For the moment, my workaround is: ./configure --with-experimental-modules --without-rlm_rediswho Regards, Brian. P.S. I notice that src/modules/stable contains "rlm_ns_mta_md5" but there appears to be no such module. Is this folded into rlm_pap now?