Hi Hui, libevent(-2.0.so.5) is at available at /lib64. pmix depends on libevent as per the spack recipe <https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/pmix/package.py>. Checking for libpmix linkage I do see that it is linked to libevent : [sas4990@quser10 lib64]$ pwd /usr/local/pmix-3.1.5/lib64 [sas4990@quser10 lib64]$ ldd libpmix.so.2.2.25 linux-vdso.so.1 => (0x00007fffbfbe7000) libm.so.6 => /lib64/libm.so.6 (0x00002b413ffb3000) libutil.so.1 => /lib64/libutil.so.1 (0x00002b41402b5000) libevent-2.0.so.5 => /lib64/libevent-2.0.so.5 (0x00002b41404b8000) libevent_pthreads-2.0.so.5 => /lib64/libevent_pthreads-2.0.so.5 (0x00002b4140700000) libz.so.1 => /home/sas4990/packages/spack/opt/spack/linux-rhel7-ivybridge/gcc-4.8.5/zlib-1.2.11-dy4p76tgbhwcznwvv7rcagzfcbxyhsbo/lib/libz.so.1 (0x00002b4140903000) libdl.so.2 => /lib64/libdl.so.2 (0x00002b4140b1a000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00002b4140d1e000) libc.so.6 => /lib64/libc.so.6 (0x00002b4140f3a000) /lib64/ld-linux-x86-64.so.2 (0x00002b413fa75000) [sas4990@quser10 lib64]$ I’m confused as to why libtool is unable to read use the dependency listing of pmix to find libevent. readelf tells me that libpmix doesn’t have rpaths set for it’s dependencies, could this be the cause of the linker being unable to find libevent ? Thank You Sajid Ali | PhD Candidate Applied Physics Northwestern University s-sajid-ali.github.io