Resolving dependencies...
cabal: Could not resolve dependencies:
trying: base-4.9.0.0/installed-4.9... (dependency of hbb-0.4.0.2)
next goal: ghc-mod (dependency of hbb-0.4.0.2)
rejecting: ghc-mod-5.6.0.0, ghc-mod-5.5.0.0, ghc-mod-5.4.0.0, ghc-mod-5.3.0.0,
ghc-mod-5.2.1.2, ghc-mod-5.2.1.1, ghc-mod-5.2.1.0, ghc-mod-5.2.0.0,
ghc-mod-5.1.1.0 (conflict: hbb => ghc-mod==5.1.0.*)
trying: ghc-mod-5.1.0.2
next goal: async (dependency of ghc-mod-5.1.0.2)
rejecting: async-2.1.1, async-2.1.0 (conflict: ghc-mod => async<2.1 &&
>=2.0.1.6)
rejecting: async-2.0.2 (conflict: base==4.9.0.0/installed-4.9..., async =>
base>=4.3 && <4.9)
rejecting: async-2.0.1.6 (conflict: base==4.9.0.0/installed-4.9..., async =>
base>=4.3 && <4.8)
rejecting: async-2.0.1.5, async-2.0.1.4, async-2.0.1.3, async-2.0.1.2,
async-2.0.1.1, async-2.0.1.0, async-2.0.0.0, async-1.4, async-1.3, async-1.2,
async-1.1, async-1.0 (conflict: ghc-mod => async<2.1 && >=2.0.1.6)
Dependency tree exhaustively searched.