Please note that as of Jan 5th 2013, GNU libidn2 isn't actually fully functional yet, so consider this a development release with an unstable API. Developed against pre-release git tree of libidn2 (internal version 0.9) Installation ~~~~~~~~~~~~ perl Build.PL ./Build ./Build test ./Build install If your local version of GNU Libidn2 is installed in a non-standard location, try the following instead of "perl Build.PL": perl Build.PL --extra_compiler_flags=-I/path/include --extra_linker_flags="-L/path/lib -lidn2" Should your runtime library search path not contain libidn2, you probably will have to set LD_LIBRARY_PATH or compile the absolute library path into the module like follows: perl Build.PL --extra_compiler_flags=-I/path/include --extra_linker_flags="-L/path/lib -lidn2 -Wl,-rpath=/path/lib"