Resolving dependencies... cabal: Could not resolve dependencies: [__0] next goal: openapi3-code-generator (user goal) [__0] rejecting: openapi3-code-generator-0.1.0.4, openapi3-code-generator-0.1.0.3 (constraint from user target requires ==0.1.0.2) [__0] trying: openapi3-code-generator-0.1.0.2 [__1] next goal: template-haskell (dependency of openapi3-code-generator) [__1] rejecting: template-haskell-2.14.0.0/installed-2.14.0.0 (conflict: openapi3-code-generator => template-haskell>=2.15.0.0 && <2.16) [__1] skipping: template-haskell-2.16.0.0 (has the same characteristics that caused the previous version to fail: excluded by constraint '>=2.15.0.0 && <2.16' from 'openapi3-code-generator') [__1] rejecting: template-haskell-2.15.0.0, template-haskell-2.14.0.0, 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) [__1] fail (backjumping, conflict set: openapi3-code-generator, template-haskell) After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: template-haskell, openapi3-code-generator