Resolving dependencies... cabal: Could not resolve dependencies: trying: base-4.9.0.0/installed-4.9... (dependency of acme-everything-2015.5.4) trying: aeson-1.0.2.1 (dependency of yesod-transloadit-0.7.1.0) trying: twentefp-eventloop-trees-0.1.2.4 (dependency of acme-everything-2015.5.4) next goal: eventloop (dependency of twentefp-eventloop-trees-0.1.2.4) rejecting: eventloop-0.8.2.0, eventloop-0.8.1.2 (conflict: aeson==1.0.2.1, eventloop => aeson>=0.8 && <0.12) rejecting: eventloop-0.8.1.1, eventloop-0.8.1.0 (conflict: base==4.9.0.0/installed-4.9..., eventloop => base>=4.8 && <4.9) rejecting: eventloop-0.8.0.1, eventloop-0.8.0.0, eventloop-0.7.0.1, eventloop-0.7.0.0, eventloop-0.6.0.0, eventloop-0.5.1.0, eventloop-0.5.0.0, eventloop-0.4.1.2, eventloop-0.4.1.1, eventloop-0.4.1.0, eventloop-0.4.0.0, eventloop-0.3.0.0, eventloop-0.2.1.2, eventloop-0.2.1.1 (conflict: twentefp-eventloop-trees => eventloop>=0.8.1.0 && <0.9.0.0) Backjump limit reached (currently 2000, change with --max-backjumps or try to run with --reorder-goals).