Tang initiated and led the Pugs project, a joint effort from the Haskell and Perl communities to implement the Perl 6 language; Tang also made contributions to internationalization and localization efforts for several Free Software programs, including SVK (a version-control software written in Perl for which Tang also wrote a large portion of the code), Request Tracker, and Slash, created Ethercalc, building on Dan Bricklin's work on WikiCalc and their work together on SocialCalc, as well as heading Traditional Chinese translation efforts for various open source-related books.