An example Makefile is included with the NDK examples shipped in the NDK sub-directory of the Documentation installed with NUKE.
For Linux, plugins will need to be built with GCC 4.1 in order to be compatible. The use of GCC 4.2+ or LLVM is unlikely to produce compatible plugins.
If you want to build with the Intel compiler, just substitute it for g++ in your makefile, however you must make sure you use the libstdc++ includes and libs from the GCC 4.1 install in order to be compatible.
On Linux, NUKE is built on a RHEL 5.4 Linux 64-bit machine, using GCC 4.1. We recommend third-party developers to use the same version of GCC.
The resulting shared object file (.so) should then be moved to your ~/.nuke directory (or otherwise into the NUKE plugin_path).
See Building & Installing Plug-ins for information on creating your first plug-in.