diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,202 @@
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diff --git a/compendium-client.cabal b/compendium-client.cabal
new file mode 100644
--- /dev/null
+++ b/compendium-client.cabal
@@ -0,0 +1,31 @@
+cabal-version:       >=1.10
+
+name:                compendium-client
+version:             0.1.0.0
+synopsis:            Client for the Compendium schema server
+description:         Client for the <https://github.com/higherkindness/compendium Compendium> schema server
+license:             Apache-2.0
+license-file:        LICENSE
+author:              Alejandro Serrano
+maintainer:          alejandro.serrano@47deg.com
+copyright:           Copyright © 2019-2020 47 Degrees. <http://47deg.com>
+category:            Network
+build-type:          Simple
+homepage:            https://github.com/higherkindness/mu-haskell
+
+library
+  exposed-modules:     Compendium.Client
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       base >=4.12 && <5
+                     , aeson
+                     , text
+                     , http-client
+                     , servant
+                     , servant-client
+                     , megaparsec
+                     , language-protobuf
+  hs-source-dirs:      src
+  default-language:    Haskell2010
+  ghc-options:         -Wall
+                       -fprint-potential-instances
diff --git a/src/Compendium/Client.hs b/src/Compendium/Client.hs
new file mode 100644
--- /dev/null
+++ b/src/Compendium/Client.hs
@@ -0,0 +1,86 @@
+{-# language DataKinds        #-}
+{-# language DeriveAnyClass   #-}
+{-# language DeriveGeneric    #-}
+{-# language TypeApplications #-}
+{-# language TypeOperators    #-}
+{-# language ViewPatterns     #-}
+{-|
+Description : Client for the Compendium schema registry
+
+Client for the Compendium schema registry
+-}
+module Compendium.Client (
+-- * Generic query of schemas
+  IdlName
+, transformation
+-- * Query Protocol Buffer schemas
+, obtainProtoBuf
+, ObtainProtoBufError(..)
+) where
+
+import           Data.Aeson
+import           Data.Char
+import           Data.Proxy
+import           Data.Text
+import           Language.ProtocolBuffers.Parser
+import           Language.ProtocolBuffers.Types
+import           Network.HTTP.Client             (Manager)
+import           Servant.API
+import           Servant.Client
+import           Text.Megaparsec
+
+import           GHC.Generics
+
+newtype Protocol
+  = Protocol { raw :: Text }
+  deriving (Eq, Show, Generic, FromJSON)
+
+-- | Interface Description Languages supported by Compendium.
+data IdlName
+  = Avro | Protobuf | Mu | OpenApi | Scala
+  deriving (Eq, Show, Generic)
+instance ToHttpApiData IdlName where
+  toQueryParam (show -> x:xs)
+    = pack $ Data.Char.toLower x : xs
+  toQueryParam _ = error "this should never happen"
+
+type TransformationAPI
+  = "protocol" :> Capture "id" Text
+               :> "transformation"
+               :> QueryParam' '[ Required ] "target" IdlName
+               :> Get '[JSON] Protocol
+
+-- | Obtain a schema from the registry.
+transformation :: Manager  -- ^ Connection details (from 'http-client').
+               -> BaseUrl  -- ^ URL in which Compendium is running.
+               -> Text     -- ^ Name that identifies the schema.
+               -> IdlName  -- ^ Format of the returned schema.
+               -> IO (Either ClientError Text)
+transformation m url ident idl
+  = runClientM (transformation' ident idl) (mkClientEnv m url)
+
+transformation' :: Text
+                -> IdlName
+                -> ClientM Text
+transformation' ident idl
+  = raw <$> client (Proxy @TransformationAPI) ident idl
+
+-- | Errors which may arise during 'obtainProtoBuf'.
+data ObtainProtoBufError
+  = OPEClient ClientError  -- ^ Error obtaining schema from Compendium
+  | OPEParse  (ParseErrorBundle Text Char)  -- ^ Obtaining the schema was OK, error parsing it
+  deriving (Show)
+
+-- | Obtain a schema from the registry,
+--   and parse it as Protocol Buffers.
+obtainProtoBuf :: Manager -> BaseUrl
+               -> Text -> IO (Either ObtainProtoBufError ProtoBuf)
+obtainProtoBuf m url ident = do
+  r <- transformation m url ident Protobuf
+  case r of
+    Left e
+      -> return $ Left (OPEClient e)
+    Right p
+      -> case parseProtoBuf p of
+          Left e   -> return $ Left (OPEParse e)
+          Right pb -> return $ Right pb
