Today I released mrcal 2.3 (the release notes are available here). Once again, in the code there are lots of useful improvements, but nothing major. The big update in this release is the documentation. Much of it was improved and extended, especially practical guides in the how-to-calibrate page and the recipes.
Major updates are imminent. I'm about to merge the cross-projection uncertainty branch and the triangulated-points-in-the-solver branch to study chessboard-less calibrations and structure from motion. Neither of these are novel, but mrcal's improved lens models and uncertainty propagation will hopefully produce better results.