This list was established thanks to contributions from participants during the 'Rocks, Dust and Ice' workshop. It is intended as a living community resources.
Light-Scattering Newsletter (maintained by L. Kolokolova), including
https://www.astro.umd.edu/~elsnews/links.htm
T-matrixcodes fro non-spherical particles https://www.giss.nasa.gov/staff/mmishchenko/t_matrix.html
Database of various computer codes for inhomogeneous particles
https://www.giss.nasa.gov/staff/mmishchenko/related.html
Various codes for the computation of (polarized) bidirectional reflectance of flat particulate layers and rough surfaces https://www.giss.nasa.gov/staff/mmishchenko/brf/
T-matrix code for aggregates
https://www.eng.auburn.edu/~dmckwski/scatcodes/
DDA collection of codes by B. Draine and P, Flatau https://www.astro.princeton.edu/~draine/DDSCAT.7.3.html
Database of the codes for light scattering by particles by T. Wriedt https://scattport.org/
Library of DDA codes by P. Flatau http://ddscat.wikidot.com/
ADDA: light scattering simulator https://github.com/adda-team/adda
simulation of digital terrain models https://github.com/pedrohasselmann/shapeimager
Small Bodies package (astropy affiliated): https://github.com/NASA-Planetary-Science/sbpy
SIRIS - single particle scattering https://wiki.helsinki.fi/display/PSR
Planetary spectrum generator https://psg.gsfc.nasa.gov/
Tutorial repository for planetary scientists: https://github.com/cjtu/plutopy
Independent review board (IRB) on improving the Planetary Data Ecosystem (PDE)
https://www.nasa.gov/feature/nasa-establishes-board-to-review-planetary-data-ecosystem
To discuss good practices: openplanetary.org
NASA Github: https://github.com/nasa
Optics software (non astro) https://omlc.org/software/index.html