diff --git a/ihaskell.cabal b/ihaskell.cabal
--- a/ihaskell.cabal
+++ b/ihaskell.cabal
@@ -7,7 +7,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.6.4.1
+version:             0.6.5.0
 
 -- A short (one-line) description of the package.
 synopsis:            A Haskell backend kernel for the IPython project.
@@ -17,7 +17,7 @@
                      a console or notebook interface. Additional packages may be installed to provide richer data visualizations. 
 
 -- URL for the project homepage or repository.
-homepage:            http://gibiansky.github.io/IHaskell/
+homepage:            http://github.com/gibiansky/IHaskell
 
 -- The license under which the package is released.
 license:             MIT
@@ -54,8 +54,8 @@
 library
   hs-source-dirs:      src
   default-language:    Haskell2010
-  build-depends:       
-                       aeson                >=0.7 && < 0.9,
+  build-depends:
+                       aeson                >=0.7 && < 0.10,
                        base                 >=4.6 && < 4.9,
                        base64-bytestring    >=1.0,
                        bytestring           >=0.10,
@@ -142,7 +142,7 @@
                        transformers         -any,
                        ghc                  >=7.6 || < 7.11,
                        here                 ==1.2.*,
-                       aeson                >=0.7 && < 0.9,
+                       aeson                >=0.7 && < 0.10,
                        bytestring           >=0.10,
                        containers           >=0.5,
                        strict               >=0.3,
@@ -166,7 +166,7 @@
     default-language: Haskell2010
     build-depends:
         ihaskell,
-        aeson >=0.6 && < 0.9,
+        aeson >=0.6 && < 0.10,
         base >=4.6 && < 4.9,
         base64-bytestring >=1.0,
         bytestring >=0.10,
diff --git a/main/Main.hs b/main/Main.hs
--- a/main/Main.hs
+++ b/main/Main.hs
@@ -71,6 +71,10 @@
 ihaskell (Args (Kernel (Just filename)) args) = do
   let kernelSpecOpts = parseKernelArgs args
   runKernel kernelSpecOpts filename
+ihaskell a@(Args (Kernel Nothing) _) = do
+  hPutStrLn stderr "No kernel profile JSON specified."
+  hPutStrLn stderr "This may be a bug!"
+  hPrint stderr a
 
 showingHelp :: IHaskellMode -> [Argument] -> IO () -> IO ()
 showingHelp mode flags act =
@@ -292,6 +296,11 @@
         , historyReply = []
         }
   return (state, reply)
+
+-- TODO: What else can be implemented?
+replyTo _ message _ state = do
+  liftIO $ hPutStrLn stderr $ "Unimplemented message: " ++ show message
+  return (state, SendNothing)
 
 -- | Handle comm messages
 handleComm :: (Message -> IO ()) -> KernelState -> Message -> MessageHeader -> Interpreter KernelState
diff --git a/src/IHaskell/IPython.hs b/src/IHaskell/IPython.hs
--- a/src/IHaskell/IPython.hs
+++ b/src/IHaskell/IPython.hs
@@ -30,6 +30,7 @@
 import           Data.Aeson (toJSON)
 import           Data.Aeson.Encode (encodeToTextBuilder)
 import           Data.Text.Lazy.Builder (toLazyText)
+import           Control.Monad (mplus)
 
 import qualified System.IO.Strict as StrictIO
 import qualified Paths_ihaskell as Paths
@@ -61,6 +62,14 @@
 kernelArgs :: [String]
 kernelArgs = ["--kernel", kernelName]
 
+ipythonCommand :: SH.Sh SH.FilePath
+ipythonCommand = do
+  jupyterMay <- SH.which "jupyter"
+  return $
+    case jupyterMay of
+      Nothing -> "ipython"
+      Just _  -> "jupyter"
+
 -- | Run the IPython command with any arguments. The kernel is set to IHaskell.
 ipython :: Bool         -- ^ Whether to suppress output.
         -> [Text]       -- ^ IPython command line arguments.
@@ -69,7 +78,8 @@
   liftIO $ installHandler keyboardSignal (CatchOnce $ return ()) Nothing
 
   -- We have this because using `run` does not let us use stdin.
-  SH.runHandles "ipython" args handles doNothing
+  cmd <- ipythonCommand
+  SH.runHandles cmd args handles doNothing
 
   where
     handles = [SH.InHandle SH.Inherit, outHandle suppress, errorHandle suppress]
@@ -103,9 +113,6 @@
   home <- maybe (error "$HOME not defined.") SH.fromText <$> SH.get_env "HOME"
   fp <$> ensure (return (home SH.</> ".ihaskell"))
 
-ipythonDir :: SH.Sh SH.FilePath
-ipythonDir = ensure $ (SH.</> "ipython") <$> ihaskellDir
-
 notebookDir :: SH.Sh SH.FilePath
 notebookDir = ensure $ (SH.</> "notebooks") <$> ihaskellDir
 
@@ -128,24 +135,35 @@
 -- | Verify that a proper version of IPython is installed and accessible.
 verifyIPythonVersion :: SH.Sh ()
 verifyIPythonVersion = do
-  pathMay <- SH.which "ipython"
+  cmd <- ipythonCommand
+  pathMay <- SH.which cmd
   case pathMay of
-    Nothing -> badIPython "No IPython detected -- install IPython 3.0+ before using IHaskell."
+    Nothing -> badIPython
+                 "No Jupyter / IPython detected -- install Jupyter 3.0+ before using IHaskell."
     Just path -> do
-      output <- T.unpack <$> SH.silently (SH.run path ["--version"])
-      case parseVersion output of
-        Just (3:_) -> return ()
-        Just (2:_) -> oldIPython
-        Just (1:_) -> oldIPython
-        Just (0:_) -> oldIPython
-        _          -> badIPython "Detected IPython, but could not parse version number."
+      stdout <- SH.silently (SH.run path ["--version"])
+      stderr <- SH.lastStderr
+      let majorVersion = join . fmap listToMaybe . parseVersion . T.unpack
+      case mplus (majorVersion stderr) (majorVersion stdout) of
+        Nothing -> badIPython $ T.concat
+                                  [ "Detected Jupyter, but could not parse version number."
+                                  , "\n"
+                                  , "(stdout = "
+                                  , stdout
+                                  , ", stderr = "
+                                  , stderr
+                                  , ")"
+                                  ]
 
+        Just version -> when (version < 3) oldIPython
+
   where
     badIPython :: Text -> SH.Sh ()
     badIPython message = liftIO $ do
       IO.hPutStrLn IO.stderr (T.unpack message)
       exitFailure
-    oldIPython = badIPython "Detected old version of IPython. IHaskell requires 3.0.0 or up."
+    oldIPython = badIPython
+                   "Detected old version of Jupyter / IPython. IHaskell requires 3.0.0 or up."
 
 -- | Install an IHaskell kernelspec into the right location. The right location is determined by
 -- using `ipython kernelspec install --user`.