Resolving dependencies... cabal: Could not resolve dependencies: [__0] trying: snaplet-customauth-0.1.1 (user goal) [__1] next goal: uri-bytestring (dependency of snaplet-customauth) [__1] rejecting: uri-bytestring-0.3.2.0, uri-bytestring-0.3.1.1, uri-bytestring-0.3.1.0, uri-bytestring-0.3.0.2, uri-bytestring-0.3.0.1, uri-bytestring-0.3.0.0 (conflict: snaplet-customauth => uri-bytestring>=0.2.3 && <0.3) [__1] trying: uri-bytestring-0.2.3.3 [__2] next goal: template-haskell (dependency of uri-bytestring) [__2] rejecting: template-haskell-2.13.0.0/installed-2.1... (conflict: uri-bytestring => template-haskell>=2.9 && <2.13) [__2] rejecting: template-haskell-2.13.0.0, template-haskell-2.12.0.0, template-haskell-2.11.1.0, template-haskell-2.11.0.0, template-haskell-2.10.0.0, template-haskell-2.9.0.0, template-haskell-2.8.0.0, template-haskell-2.7.0.0, template-haskell-2.6.0.0, template-haskell-2.5.0.0, template-haskell-2.4.0.1, template-haskell-2.4.0.0, template-haskell-2.3.0.1, template-haskell-2.3.0.0, template-haskell-2.2.0.0 (constraint from non-upgradeable package requires installed instance) After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: template-haskell, uri-bytestring, base, snaplet-customauth