ddollar/heroku-buildpack-apt — pull request #4 by wless1 (2014-08-13 16:20:29+00:00)
Title: Set LIBRARY_PATH for compile-time linking

For apps that need to compile dependencies that are linked against
newly installed apt development libraries, this change lets the linker
find the library properly.

See http://stackoverflow.com/questions/4250624/ld-library-path-vs-library-path