[Haskell-cafe] What is the most modern associative list in types?

Hello cafe. I am trying to express some environment in types to constrain program behavour. For this I need associative list of types, something along the lines of [(Symbol, *)] so that I can lookup on "variable" name and get type associated with it. I looked into HList library but it does not provide one most generally useful way (albeit there are dozen or so of ways in there). So where can I get most modern HList-like library? Or what should I read to get most modern HList myself?