This is an experimental optics library for F# and is very much work-in-progress. The main question is whether a kind of encoding of van Laarhoven style lenses could lead to a practical optics library for F#.
Here is a Bash script to get started:
git clone --recursive https://github.com/polytypic/FsOptics.git
cd FsOptics
./play
After a moment of processing, you should be in F# interactive and ready to play.