I would like to bring some attention to two projects that I have been working on.
PhylogeNi - A library for working with phylogenetic trees (evolutionary trees).
BioSeq - A library for working with biological sequence data such as DNA.
Others have done something similar to the BioSeq package but I have come up with a different approach that provides more safety without sacrificing performance as far as I can tell.
Both currently only implement some pretty basic things but they should significantly lower the bar to doing some more interesting stuff. I have put a good amount of work recently into polishing up what currently exists, implementing a lot of tests, creating basic documentation, and setting up actions for continuous integration. I'm hoping all of this might entice some people to have a look, give some feedback, and possibly make contributions.
Thank you to all of you that have answered mine and other people's questions on this forum! It has been an important resource.