LogFAQs > #973813626

Depending on how long it's been, not a whole lot. 1.0 launched in August 2020, but even that didn't have a lot of major features. I think the last major addition was adding cut/copy/paste functionality in 0.17, in February 2019. Everything since then has mostly been optimizations (though I hesitate to downplay those because they include something like a 50-fold increase in UPS for megabase-scale belts), quality of life fixes, or smaller features (like train limits and the spidertron). The game has certainly still evolved, but it was more or less feature-complete for a solid year or so prior to leaving Early Access three years ago.

Now, on the modding front, there's quite a bit of new stuff to play with there, since that scene is constantly evolving. But then that's a given.