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Resolving dependencies...
Starting     transformers-compat-0.6.3
Building     transformers-compat-0.6.3
Failed to install transformers-compat-0.6.3
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/transformers-compat-0.6.3-8J5sQDqjcykKMT9EWJuWmO.log ):
cabal: Entering directory '/tmp/cabal-tmp-2121/transformers-compat-0.6.3'
Configuring transformers-compat-0.6.3...
Preprocessing library for transformers-compat-0.6.3..
Building library for transformers-compat-0.6.3..
[1 of 4] Compiling Control.Monad.Trans.Instances ( src/Control/Monad/Trans/Instances.hs, dist/build/Control/Monad/Trans/Instances.o )

src/Control/Monad/Trans/Instances.hs:610:10: error:
    Duplicate instance declarations:
      instance MonadFix m => MonadFix (ListT m)
        -- Defined at src/Control/Monad/Trans/Instances.hs:610:10
      instance [safe] MonadFix m => MonadFix (ListT m)
        -- Defined in ‘Control.Monad.Trans.List’
    |
610 | instance (MonadFix m) => MonadFix (ListT m) where
    |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
cabal: Leaving directory '/tmp/cabal-tmp-2121/transformers-compat-0.6.3'
cabal: Error: some packages failed to install:
transformers-compat-0.6.3-8J5sQDqjcykKMT9EWJuWmO failed during the building
phase. The exception was:
ExitFailure 1