Hello. I'm posting this here on the off chance it may be useful to others. It's basically an updated rehash of my older post on this.   **Building Latest prb+ (2.5.1.5test 2018-Jan-14 12:06) on Mac OS X 10.13.2   1) install xcode and command line tools   2) install automake, autoconf, libpng, libsdl2, libsdl2_net, libsdl2_image, libsdl2_mixer  (I use MacPorts for this)   3) prb+ configure scripts look in a limited number of places for the GL libraries, and with every OS update Apple loves to move these to new obscure locations. My lazy solution to this is to make symlinks in the directories where ./configure will look that point to where they actually live: (@Jon might find this helpful) sudo ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk/System/Library/Frameworks/OpenGL.framework/Versions/Current/Headers/ /usr/local/include/GL sudo ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk/System/Library/Frameworks/OpenGL.framework/Versions/Current/Libraries/libGL.tbd /usr/local/lib/libGL.tbd sudo ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk/System/Library/Frameworks/OpenGL.framework/Versions/Current/Libraries/libGLU.tbd /usr/local/lib/libGLU.tbd   4) if you used MacPorts to accomplish step 2, add the /opt/ directories to search paths export C_INCLUDE_PATH=$C_INCLUDE_PATH:/opt/local/include export LIBRARY_PATH=$LIBRARY_PATH:/opt/local/lib     5) install as per usual svn co https://svn.prboom.org/repos/branches/prboom-plus-24/prboom2/ cd prboom2 ./bootstrap ./configure make sudo make install   *** UPDATE - 12/22/2018 - OS X MOJAVE ***   Another year, another OS update, another recompiling of prb+ ;D. Here are the following alterations I had to make to the above steps to get everything running os x 10.14.2:   3) OpenGL library paths have migrated from MacOSX10.13.sdk/ to MacOSX10.14.sdk/   4) For some reason setting these variables before ./configure was no longer percolating down to the makefiles. Use this instead:   export CPPFLAGS=-I/opt/local/include export LDFLAGS=-L/opt/local/lib   Some notes: Ever since the Mojave update GL graphics seems to have taken a substantial performance hit. Kind of a bummer. I'm guessing it has something to do with this.