5 files changed, 12 insertions, 8 deletions

diff --git a/default.nix b/default.nix
index b1404ef..a392583 100644
--- a/default.nix
+++ b/default.nix
@@ -4,7 +4,7 @@
 }:
 mkDerivation {
   pname = "hmacaroons";
-  version = "0.2.0.0";
+  version = "0.4.0.0";
   src = ./.;
   buildDepends = [
     attoparsec base base64-bytestring byteable bytestring cereal
@@ -12,7 +12,8 @@ mkDerivation {
   ];
   testDepends = [
     attoparsec base base64-bytestring byteable bytestring cereal
-    cryptohash either hex QuickCheck tasty tasty-hunit tasty-quickcheck
+    cryptohash deepseq either hex QuickCheck tasty tasty-hunit
+    tasty-quickcheck transformers
   ];
   homepage = "https://github.com/jtanguy/hmacaroons";
   description = "Haskell implementation of macaroons";
diff --git a/hmacaroons.cabal b/hmacaroons.cabal
index 83b2cd7..85958b9 100644
--- a/hmacaroons.cabal
+++ b/hmacaroons.cabal
@@ -1,5 +1,5 @@
 name:                hmacaroons
-version:             0.3.0.0
+version:             0.4.0.0
 synopsis:            Haskell implementation of macaroons
 description:
   Hmacaroons is a pure haskell implementation of macaroons. It aims to
@@ -58,7 +58,7 @@ library
                        Crypto.Macaroon.Verifier.Internal
   build-depends:  base >=4 && < 5,
                   attoparsec >=0.12,
-                  transformers >= 0.4,
+                  transformers >= 0.3,
                   bytestring >=0.10,
                   base64-bytestring >= 1.0,
                   byteable >= 0.1 && <0.2,
@@ -110,4 +110,4 @@ test-suite test
                   tasty-quickcheck >= 0.8,
                   QuickCheck >= 2.8,
                   deepseq >= 1.1,
-                  transformers >= 0.4
+                  transformers >= 0.3
diff --git a/src/Crypto/Macaroon/Verifier.hs b/src/Crypto/Macaroon/Verifier.hs
index a739437..4fc6aff 100644
--- a/src/Crypto/Macaroon/Verifier.hs
+++ b/src/Crypto/Macaroon/Verifier.hs
@@ -23,11 +23,13 @@ module Crypto.Macaroon.Verifier (
 ) where
 
 
-import           Control.Monad
+import           Control.Applicative
+import           Control.Monad hiding (forM)
 import           Control.Monad.IO.Class
 import           Data.Attoparsec.ByteString
 import           Data.Attoparsec.ByteString.Char8
 import           Data.Bool
+import           Data.Traversable
 import qualified Data.ByteString                  as BS
 import           Data.Either.Combinators
 
@@ -68,7 +70,7 @@ import           Crypto.Macaroon.Verifier.Internal
 -- caveat, parsed it and invalidated it;
 -- * 'Just' ('Right' '()') if the verifier has successfully verified the
 -- given caveat
-verify :: MonadIO m => Secret -> [Caveat -> m (Maybe (Either ValidationError ()))] -> Macaroon -> m (Either ValidationError Macaroon)
+verify :: (Functor m, MonadIO m) => Secret -> [Caveat -> m (Maybe (Either ValidationError ()))] -> Macaroon -> m (Either ValidationError Macaroon)
 verify secret verifiers m = join <$> forM (verifySig secret m) (verifyCavs verifiers)
 
 
diff --git a/src/Crypto/Macaroon/Verifier/Internal.hs b/src/Crypto/Macaroon/Verifier/Internal.hs
index 73eb66a..5126b2e 100644
--- a/src/Crypto/Macaroon/Verifier/Internal.hs
+++ b/src/Crypto/Macaroon/Verifier/Internal.hs
@@ -58,7 +58,7 @@ verifySig k m = bool (Left SigMismatch) (Right m) $
     derivedKey = toBytes (hmac "macaroons-key-generator" k :: HMAC SHA256)
 
 -- | Given a list of verifiers, verify each caveat of the given macaroon
-verifyCavs :: MonadIO m
+verifyCavs :: (Functor m, MonadIO m)
            => [Caveat -> m (Maybe (Either ValidationError ()))]
            -> Macaroon
            -> m (Either ValidationError Macaroon)
diff --git a/test/Crypto/Macaroon/Instances.hs b/test/Crypto/Macaroon/Instances.hs
index 6348c56..019c094 100644
--- a/test/Crypto/Macaroon/Instances.hs
+++ b/test/Crypto/Macaroon/Instances.hs
@@ -11,6 +11,7 @@ This test suite is based on the pymacaroons test suite:
 -}
 module Crypto.Macaroon.Instances where
 
+import           Control.Applicative
 import           Control.Monad
 import           Data.Byteable
 import qualified Data.ByteString       as BS