I first saw Immer in Brad Schiff’s React for the Rest Of Us Course and I was impressed. Although there is not a lot else out there on Youtube.
Redux seems to be more popular although the downloads are slightly higher for Immer although not sure if this is an Apples to Apples comparison. (5.8 vs 6.9m weekly downloads). The “use-immer” package only has 64k weekly.
immer docs here.
Smashing article here.