Hebcal is a perpetual Jewish calendar program, implemented in C. The key routines are translations of Dershowitz & Reingold's lisp code in GNU-Emacs 18. Hebcal offers several convenience routines that make it a good fit for generating calendars for PDAs and personal calendars.
We're using GitHub for further development on hebcal. Go to the hebcal project page to report a bug, get the latest release, or browse the source.
Hebcal is made available for free under the Gnu Public License. However, I would like to hear from you. If you like hebcal, send me a message! If you don't like hebcal, well, let me know also, but be gentle.
If you wish to fund future hebcal development, you can donate here: