Resolving dependencies...
cabal: Could not resolve dependencies:
next goal: wai-handler-devel (user goal)
rejecting: wai-handler-devel-2.0.0.2, 2.0.0.1, 2.0.0, 1.3.0.6, 1.3.0.5,
1.3.0.4, 1.3.0.3, 1.3.0.2 (global constraint requires ==1.3.0.1)
trying: wai-handler-devel-1.3.0.1
trying: base-4.8.1.0/installed-4f7... (dependency of
wai-handler-devel-1.3.0.1)
next goal: hint (dependency of wai-handler-devel-1.3.0.1)
rejecting: hint-0.4.2.3, 0.4.2.2, 0.4.2.1, 0.4.2.0, 0.4.1.0, 0.4.0.0
(conflict: wai-handler-devel => hint>=0.3.2.3 && <0.4)
trying: hint-0.3.3.7
next goal: ghc-mtl (dependency of hint-0.3.3.7)
rejecting: ghc-mtl-1.2.1.0, 1.2.0.0, 1.1.0.0 (conflict: hint =>
ghc-mtl<1.1.0.0)
rejecting: ghc-mtl-1.0.1.2 (conflict: base==4.8.1.0/installed-4f7..., ghc-mtl
=> base<4.7)
rejecting: ghc-mtl-1.0.1.1 (conflict: base==4.8.1.0/installed-4f7..., ghc-mtl
=> base<4.6)
rejecting: ghc-mtl-1.0.1.0 (conflict: base==4.8.1.0/installed-4f7..., ghc-mtl
=> base>=4 && <4.4)
rejecting: ghc-mtl-1.0.0.0 (conflict: hint => ghc-mtl>=1.0.1.0)
Backjump limit reached (change with --max-backjumps).