diff --git a/compendium-client.cabal b/compendium-client.cabal
--- a/compendium-client.cabal
+++ b/compendium-client.cabal
@@ -1,5 +1,5 @@
 name:          compendium-client
-version:       0.2.0.0
+version:       0.2.1.1
 synopsis:      Client for the Compendium schema server
 description:
   Client for the <https://github.com/higherkindness/compendium Compendium> schema server
@@ -22,14 +22,14 @@
 library
   exposed-modules:  Compendium.Client
   build-depends:
-      aeson
-    , base               >=4.12 && <5
-    , http-client
-    , language-protobuf
-    , megaparsec
-    , servant
-    , servant-client
-    , text
+      aeson              >=1.4   && <2
+    , base               >=4.12  && <5
+    , http-client        >=0.6.4 && <0.7
+    , language-protobuf  >=1.0.1 && <1.1
+    , megaparsec         >=8     && <10
+    , servant            >=0.16  && <0.19
+    , servant-client     >=0.16  && <0.19
+    , text               >=1.2   && <2
 
   hs-source-dirs:   src
   default-language: Haskell2010
diff --git a/src/Compendium/Client.hs b/src/Compendium/Client.hs
--- a/src/Compendium/Client.hs
+++ b/src/Compendium/Client.hs
@@ -79,8 +79,8 @@
   r <- transformation m url ident Protobuf
   case r of
     Left e
-      -> return $ Left (OPEClient e)
+      -> pure $ Left (OPEClient e)
     Right p
       -> case parseProtoBuf p of
-          Left e   -> return $ Left (OPEParse e)
-          Right pb -> return $ Right pb
+          Left e   -> pure $ Left (OPEParse e)
+          Right pb -> pure $ Right pb