# Calixir **URL:** \ **Category:** Announcing\ **Tags:** library, calendars, converters\ **Created:** [July 24, 2020, 7:09pm UTC](https://forum.elixirforum.com/t/calixir/33334 "2020-07-24T19:09:20Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![rengel](https://forum.elixirforum.com/user_avatar/forum.elixirforum.com/rengel/32/20073_2.png) [@rengel](https://forum.elixirforum.com/u/rengel)\ **Post date:** [July 24, 2020, 7:09pm UTC](https://forum.elixirforum.com/t/calixir/33334/1 "2020-07-24T19:09:20Z")
> **[calixir](https://hex.pm/packages/calixir)** > > Calixir is a port of the Lisp calendar software calendrica-4.0.cl > by Nachum Dershowitz and Edward M. Reingold to Elixir. ---
**Author:** ![kip](https://forum.elixirforum.com/user_avatar/forum.elixirforum.com/kip/32/1440_2.png) [@kip](https://forum.elixirforum.com/u/kip)\ **Post date:** [July 25, 2020, 7:06am UTC](https://forum.elixirforum.com/t/calixir/33334/2 "2020-07-25T07:06:27Z")
Well done, it’s a fascinating topic - so much so I’ve somehow ended up buying three different revisions of the book 🙂 Just noting that D&R assert all rights over their code, _formulas_ and _calendar data_ and grant a license for personal use only. I would propose you note this in both your packages in case someone accidentally believes the libraries can be used in commercial software without a specific license grant from D&R. ---
**Author:** ![rengel](https://forum.elixirforum.com/user_avatar/forum.elixirforum.com/rengel/32/20073_2.png) [@rengel](https://forum.elixirforum.com/u/rengel)\ **Post date:** [July 25, 2020, 3:57pm UTC](https://forum.elixirforum.com/t/calixir/33334/3 "2020-07-25T15:57:41Z")
Thank you for your kind feedback and your suggestion! I integrated the text that was used for the calcalc package ([GitHub - ferd/calcalc: Calendrical Calculations; Erlang port of Dershowitz & Reingold's algorithms. · GitHub](https://github.com/ferd/calcalc)) into the README.md files of my pakages.