Resolving dependencies... cabal: Could not resolve dependencies: next goal: stripe (user goal) rejecting: stripe-0.8.3, 0.8.1, 0.8.0, 0.7.0, 0.6.0, 0.5.0.0 (global constraint requires ==0.4.0.0) trying: stripe-0.4.0.0 next goal: mtl (dependency of stripe-0.4.0.0) rejecting: mtl-2.2.1, 2.2.0.1, 2.2 (conflict: stripe => mtl>=2.1 && <2.2) trying: mtl-2.1.3.1 next goal: transformers (dependency of mtl-2.1.3.1) rejecting: transformers-0.4.2.0/installed-21d..., 0.4.3.0, 0.4.2.0, 0.4.1.0 (conflict: mtl => transformers==0.3.*) trying: transformers-0.3.0.0 next goal: http-conduit (dependency of stripe-0.4.0.0) rejecting: http-conduit-2.1.8, 2.1.7.2, 2.1.7.1, 2.1.7, 2.1.6, 2.1.5.1, 2.1.5, 2.1.4.7, 2.1.4.5, 2.1.4.4, 2.1.4.3, 2.1.4.2, 2.1.4.1, 2.1.4, 2.1.3, 2.1.2.3, 2.1.2.2, 2.1.2.1, 2.1.2, 2.1.1, 2.1.0, 2.0.0.10, 2.0.0.9, 2.0.0.8, 2.0.0.7, 2.0.0.6, 2.0.0.5, 2.0.0.4, 2.0.0.3, 2.0.0.2, 2.0.0.1, 2.0.0 (conflict: stripe => http-conduit>=1.4.1.2 && <2.0) trying: http-conduit-1.9.6 trying: transformers-base-0.4.4 (dependency of http-conduit-1.9.6) trying: transformers-compat-0.4.0.4 (dependency of transformers-base-0.4.4) trying: transformers-compat-0.4.0.4:-two rejecting: transformers-compat-0.4.0.4:-three (conflict: transformers==0.3.0.0, transformers-compat-0.4.0.4:three => transformers>=0.4.1 && <0.5) rejecting: transformers-compat-0.4.0.4:+three (manual flag can only be changed explicitly) Backjump limit reached (change with --max-backjumps).