This is an alternate implementation for Dict in Elm. The implementation used is Left-Leaning Red-Black Tree, or LLRB for short. This library is API-compatible, so it should be a drop in replacement. Simply use the following import-statement in your code:
import Dict.LLRB as Dict exposing (Dict)
You can expect better performance for insert, remove, union, intersect, diff and any operation implemented with these functions.