diff --git a/criu-rpc.cabal b/criu-rpc.cabal
--- a/criu-rpc.cabal
+++ b/criu-rpc.cabal
@@ -2,7 +2,7 @@
 -- documentation, see http://haskell.org/cabal/users-guide/
 
 name:                criu-rpc
-version:             0.0.1
+version:             0.0.2
 synopsis:            CRIU RPC client.
 description:         Low level client for the CRIU RPC API.
 bug-reports:         https://github.com/wayofthepie/haskell-criu-rpc/issues
@@ -29,10 +29,10 @@
     base >=4.9 && <5
     , criu-rpc-types >= 0.0.0.2 && < 1.0
     , lens-family >= 1.2.1 && < 1.3
-    , process
-    , proto-lens
-    , network
-    , text
-    , unix
+    , process >= 1.4.0.0 && < 1.5
+    , proto-lens >= 0.1.0.4 && < 0.1.1.0
+    , network >= 2.6.0.0 && < 2.7
+    , text >= 1.2.1.0 && < 1.3
+    , unix >= 2.7.0.0 && < 2.8
   hs-source-dirs:      src
   default-language:    Haskell2010
diff --git a/src/Criu.hs b/src/Criu.hs
--- a/src/Criu.hs
+++ b/src/Criu.hs
@@ -29,13 +29,16 @@
 import Control.Exception.Base (IOException, bracket, try)
 import GHC.Int
 import Lens.Family2 ((.~))
-import Data.ProtoLens (build, decodeMessage, encodeMessage)
+import Data.ProtoLens.Message (build)
+import Data.ProtoLens.Encoding (decodeMessage, encodeMessage)
 import Proto.Criu.Rpc
 import Network.Socket (Family(AF_UNIX), SocketType(SeqPacket), SockAddr(SockAddrUnix), close, connect, socket)
 import Network.Socket.ByteString (recv, send)
 import System.Posix.IO
 import System.Posix.Types
 
+
+--------------------------------------------------------------------------------
 {- $requests
 The simplest example of a call to CRIU is a __/check/__ request. For convenience
 this module re-exports some libraries used for building 'Criu_req's.
@@ -87,7 +90,7 @@
     Left (e :: IOException) -> pure . Left . show $ e
 
 
--- | Send request to a criu service. Takes a filepath to the criu service
+-- | Send a request to a criu service. Takes a filepath to the criu service
 -- socket and a criu request. Returns an `Either` of the response or a
 -- `String` representing an error if there is an issue decoding the
 -- response from the criu service.
@@ -104,13 +107,9 @@
     (close)
     (\sock -> f sock)
 
-
--- | Build some options.
-criuOpts :: Int32 -> Int32 -> Criu_opts
-criuOpts procId dirFd =
-  build ((imagesDirFd .~ dirFd) . (pid .~ procId) . (shellJob .~ True))
+--------------------------------------------------------------------------------
 {- $requestbuilders
-To build 'Criu_req''s you will need '.~' from "Lens.Family2", 'build' from
+To build 'Criu_req''s you will need '.~' from "Lens.Family2", 'Data.ProtoLens.Message.build' from
 "Data.ProtoLens" and of course the lenses and types from "Proto.Criu.Rpc".
 
 Above we saw a simple /check/ request, the next example is a /dump/ request. This one is
@@ -162,6 +161,7 @@
 dumpRequestOpts :: Fd -> Int32 -> Criu_opts
 dumpRequestOpts fd procId =
   build ((imagesDirFd .~ (fromIntegral fd)) . (pid .~ procId))
+
 
 -- | Open a directory, returning its file descriptor.
 -- Caution - make sure to close the file descriptor! Can use 'closeDirFd'.