diff --git a/src/Tahoe/SDMF/Internal/Converting.hs b/src/Tahoe/SDMF/Internal/Converting.hs
index 84672ac9ff13d03f308aab2d88d842f201774170..abd00f635600f0a56551bc1113de249f23f766ca 100644
--- a/src/Tahoe/SDMF/Internal/Converting.hs
+++ b/src/Tahoe/SDMF/Internal/Converting.hs
@@ -7,6 +7,7 @@
 -}
 module Tahoe.SDMF.Internal.Converting where
 
+import Control.Monad.Fail (MonadFail)
 import Data.Int (Int64)
 import Data.Word (Word16, Word32, Word64, Word8)
 
diff --git a/src/Tahoe/SDMF/Internal/Encoding.hs b/src/Tahoe/SDMF/Internal/Encoding.hs
index b34b91c56e0028f61b4bc5d2200993ccde4eb5c9..5d98a76f3e959e77d88e232aee347728976062e3 100644
--- a/src/Tahoe/SDMF/Internal/Encoding.hs
+++ b/src/Tahoe/SDMF/Internal/Encoding.hs
@@ -5,6 +5,7 @@
 -}
 module Tahoe.SDMF.Internal.Encoding where
 
+import Control.Monad.Fail (MonadFail)
 import Control.Monad (when)
 import Control.Monad.IO.Class (MonadIO (liftIO))
 import Crypto.Hash (digestFromByteString)
diff --git a/tahoe-ssk.cabal b/tahoe-ssk.cabal
index abbeaf2456f15f3c39a70ee73a9d4da7f3b3c43f..f6b99a4bff38c047d29ccb320e14d1bd1d21fd2e 100644
--- a/tahoe-ssk.cabal
+++ b/tahoe-ssk.cabal
@@ -135,7 +135,7 @@ test-suite tahoe-ssk-test
   build-depends:
     , asn1-encoding
     , asn1-types
-    , base            ^>=4.14.3.0
+    , base
     , base32
     , binary
     , bytestring
diff --git a/test/Spec.hs b/test/Spec.hs
index 17d43b89b6f9c4a6b1013e57da86cc539b6f3ab6..70e7b1e1cf493701c3be927dc74c9694210a8cd0 100644
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -8,6 +8,7 @@ import Hedgehog (
     tripping,
  )
 
+import Control.Monad.Fail (MonadFail)
 import Control.Monad (when)
 import Control.Monad.IO.Class (liftIO)
 import Crypto.Cipher.Types (makeIV)