cabal: cannot configure backdropper-1.2. It requires base >=2 && <4
For the dependency on base >=2 && <4 there are these packages: base-3.0.3.1
and base-3.0.3.2. However none of them are available.
base-3.0.3.1 was excluded because of the top level dependency base -any
base-3.0.3.2 was excluded because of the top level dependency base -any