> I learned Haskell a few years ago, enough to read it, but not fluent enough to comfortably write it.

Several years ago I tried to learn Haskell, and while I got to the point where I could write Haskell code, I found reading it nearly impossible. Even code I'd written a day or two earlier I found extremely difficult to decipher. While I learned some interesting things from the time I spent trying to learn Haskell, I eventually gave up on ever actually using it.