Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: transformers-compat (dependency of clafer-0.4.1)
rejecting: transformers-compat-0.5.1.4, transformers-compat-0.5.1.3,
transformers-compat-0.5.1.2, transformers-compat-0.5.0.4,
transformers-compat-0.5.0.3, transformers-compat-0.5.0.2 (conflict: clafer =>
transformers-compat>=0.3 && <0.5)
trying: transformers-compat-0.4.0.4
trying: tagged-0.8.5 (dependency of lens-4.15.1)
rejecting: tagged-0.8.5:+transformers (conflict: transformers-compat==0.4.0.4,
tagged-0.8.5:transformers => transformers-compat>=0.5 && <1)
rejecting: tagged-0.8.5:-transformers (manual flag can only be changed
explicitly)
Dependency tree exhaustively searched.