MongoDB

you need edit config ld.so.conf after you installed C driver for MongoDB

After you installed C driver from source, it print below help message, you
should take care.

Libraries have been installed in:
   /usr/local/lib

If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the '-LLIBDIR'
flag during linking and do at least one of the following:
   - add LIBDIR to the 'LD_LIBRARY_PATH' environment variable
     during execution
   - add LIBDIR to the 'LD_RUN_PATH' environment variable
     during linking
   - use the '-Wl,-rpath -Wl,LIBDIR' linker flag
   - have your system administrator add LIBDIR to '/etc/ld.so.conf'

it means that you should append /usr/local/lib to LD_LIBRARY_PATH env,
and let your linker can find mongoc lib

if you have root permision, the easy way is to edit /etc/ld.so.conf ,
after you do that, you should run below command, and make sure everything is
fine

$ ldconfig
$ ldconfig -p | grep mongo
        libmongoc-1.0.so.0 (libc6,x86-64) => /usr/local/lib/libmongoc-1.0.so.0
        libmongoc-1.0.so (libc6,x86-64) => /usr/local/lib/libmongoc-1.0.so