UEFITool is a Qt-based GUI tool that works on Mac/Windows/Linux. In addition to the main Qt-based GUI tool, the project also has a few other command line tools, UEFIExtract, UEFIFind, UEFIDump. And there are two codebases on Github, master and new-engine.
Some of the command line tools have been changing: UEFIDump was a tool that dumped info. UEFIDump is now gone, replaced by UEFIExtract with the “unpack” option (the “dump” option is related).
UEFIDump/UEFIExtract aside, UEFIFind is also useful to find information: