diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -35,11 +35,11 @@
 ![](data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==)
 
 ## Usage
-Here's a simple Hylogen program, saved as `Main.hs`:
+Here's a simple Hylogen program, saved as `Example.hs`:
 
 ```haskell
 
-module Main where
+module Example where
 import Hylogen.WithHylide
 
 color :: Vec4
@@ -50,7 +50,9 @@
     a = sum [ cos (x_ uvN * f time + x_ mouse )
             , sin (y_ uvN * f time + y_ mouse )
             ]
-main = putStrLn . toGLSL $ color
+
+output :: Program
+output = toProgram color
 ```
 
 Run hylide:
@@ -87,7 +89,7 @@
 }
 ```
 
-Hylide will recompile and and rerun `main` on file changes, sending fresh shaders to the WebGL context via websockets.
+Hylide will recompile on file changes, sending fresh shaders to the WebGL context via websockets.
 
 
 
diff --git a/app/Main.hs b/app/Main.hs
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -4,11 +4,12 @@
 
 import Paths_hylogen (getDataFileName)
 import Control.Concurrent
+import Control.Monad
 import Data.Aeson
 import qualified Data.ByteString.Lazy.Char8 as LBS8
 
 import qualified Data.Text as T
-import Network.WebSockets
+import qualified Network.WebSockets as S
 import System.Environment (getArgs)
 import System.FilePath
 import System.FSNotify
@@ -19,6 +20,10 @@
 import Network.Wai.Handler.Warp
 import Network.HTTP.Types (status200, status404)
 
+import qualified Language.Haskell.Interpreter as I
+import qualified Control.Exception as E
+
+
 data Msg = Err String
          | Code String
          deriving (Show)
@@ -28,54 +33,81 @@
     Err str -> object [ "error" .= str]
     Code str -> object [ "code" .= str]
 
-
 main :: IO ()
-main = getArgs >>= \case
-  [pathToWatch] -> main' pathToWatch
-  _ -> error "Error: Name a file to watch!"
+main = do
+  getArgs >>= \case
+    [pathToWatch] -> main' pathToWatch
+    _ -> error "Error: Name a file to watch!"
 
 main' :: FilePath ->  IO ()
 main' pathToWatch = do
-  _ <- forkIO serveIndex
-  serveGLSL pathToWatch
+  tid1 <- forkIO serveIndex
+  tid2 <- forkIO $ serveGLSL pathToWatch
+  putStrLn "Press enter to exit."
+  void getLine
+  -- let fn = do
+  --       killThread tid1
+  --       killThread tid2
+  --       die "diee"
+  -- installHandler keyboardSignal (Catch fn) Nothing
 
+
+
 serveGLSL :: FilePath -> IO ()
 serveGLSL pathToWatch = do
   withManager
-    $ runServer "127.0.0.1" 8080
+    $ S.runServer "127.0.0.1" 8080
     . handleConnection pathToWatch
+  return ()
 
-handleConnection :: FilePath -> WatchManager -> PendingConnection -> IO ()
+handleConnection :: FilePath -> WatchManager -> S.PendingConnection -> IO ()
 handleConnection pathToWatch mgr pending = do
    let (dirToWatch, _) = splitFileName pathToWatch
-   connection <- acceptRequest pending
+   connection <- S.acceptRequest pending
 
    -- let send = sendTextData connection . T.pack
-   let send = sendTextData connection
+   let send = S.sendTextData connection
    let update = do
          msg <- getCodeOrError pathToWatch
          send . encode $ msg
 
-   let onChange e = case e of
-         Modified _ _ -> update
-         _ -> return ()
+   let onChange e = do
+         case e of
+           Modified _ _ -> update
+           _ -> return ()
    update
    _ <- watchDir mgr dirToWatch (const True) onChange
    _ <- getLine -- temp hack to keep the socket open
    return ()
 
+interp :: FilePath -> I.InterpreterT IO String
+interp fp = do
+  I.loadModules [fp]
+  I.setImports [takeBaseName fp]
+  I.eval "output"
+
 getCodeOrError :: FilePath -> IO Msg
-getCodeOrError pathToWatch = do
-   -- TODO: more robust paths!:
-   -- c <- readFile pathToWatch
-   let (dirToWatch, _) = splitFileName pathToWatch
-   (ec, stdout, stderr) <- readProcessWithExitCode "runghc" [
-        "-i"++dirToWatch
-      , pathToWatch
-      ] ""
-   case ec of
-     ExitSuccess   -> return (Code stdout)
-     ExitFailure _ -> return (Err stderr)
+getCodeOrError path = do
+  I.runInterpreter (interp path) >>= return . \case
+    Left err -> case err of
+      I.UnknownError str -> Err str
+      I.WontCompile errors -> Err . mconcat $ I.errMsg <$> errors
+      I.NotAllowed str -> Err str
+      I.GhcException str -> Err str
+    Right str -> Code str
+
+-- getCodeOrError' :: FilePath -> IO Msg
+-- getCodeOrError' pathToWatch = do
+--    -- TODO: more robust paths!:
+--    -- c <- readFile pathToWatch
+--    let (dirToWatch, _) = splitFileName pathToWatch
+--    (ec, stdout, stderr) <- readProcessWithExitCode "runghc" [
+--         "-i"++dirToWatch
+--       , pathToWatch
+--       ] ""
+--    case ec of
+--      ExitSuccess   -> return (Code stdout)
+--      ExitFailure _ -> return (Err stderr)
 
 serveIndex :: IO ()
 serveIndex = do
diff --git a/hylogen.cabal b/hylogen.cabal
--- a/hylogen.cabal
+++ b/hylogen.cabal
@@ -1,5 +1,5 @@
 name:                hylogen
-version:             0.1.2.3
+version:             0.1.3.0
 synopsis:            an EDSL for live-coding fragment shaders
 description:         an EDSL for live-coding fragment shaders
 homepage:            https://github.com/sleexyz/hylogen
@@ -27,7 +27,7 @@
                      , Hylogen.WithHylide
                      , Hylogen.WithHylide.Core
                      , Hylogen.WithHylide.Util
-  build-depends:       base >=4.8 && <4.9
+  build-depends:       base >= 4.8 && <=4.9
                      , vector-space
                      , data-reify
   hs-source-dirs:      src
@@ -45,6 +45,7 @@
                      , text
                      , websockets
                      , aeson
+                     , hint
                      , wai >=3.2 && <3.3
                      , http-types >=0.9 && <0.10
                      , warp >=3.2 && <3.3
diff --git a/src/Hylogen.hs b/src/Hylogen.hs
--- a/src/Hylogen.hs
+++ b/src/Hylogen.hs
@@ -1,7 +1,9 @@
 module Hylogen ( module Hylogen.Types
                , module Hylogen.Globals
+               , module Hylogen.Program
                ) where
 
 import           Hylogen.Globals
 import           Hylogen.Types
+import           Hylogen.Program (toProgram, Program)
 
diff --git a/src/Hylogen/Program.hs b/src/Hylogen/Program.hs
--- a/src/Hylogen/Program.hs
+++ b/src/Hylogen/Program.hs
@@ -10,6 +10,7 @@
 import System.IO.Unsafe
 
 import Hylogen.Expr
+import Hylogen.Types.Vec (Vec4)
 
 newtype Id = Id Int
 instance Show Id where
@@ -45,7 +46,14 @@
 
 
 -- | Returns a program given an expression in closed untyped form
-toProgram :: ExprMono -> Function
-toProgram v = unsafePerformIO $ do
+monoToProgram :: ExprMono -> Function
+monoToProgram v = unsafePerformIO $ do
   Graph nodes _ <- reifyGraph v
   return . Function $ NewAssign <$> nodes
+
+-- | A GLSL program. Currently synonym for Function.
+type Program = Function
+
+-- | Helper function from a Vec4 to A GLSL Program, with sharing.
+toProgram :: Vec4 -> Program
+toProgram = monoToProgram . toMono
diff --git a/src/Hylogen/WithHylide/Core.hs b/src/Hylogen/WithHylide/Core.hs
--- a/src/Hylogen/WithHylide/Core.hs
+++ b/src/Hylogen/WithHylide/Core.hs
@@ -3,20 +3,15 @@
 import           Data.Monoid
 import           Hylogen
 import           Hylogen.Expr
-import           Hylogen.Program  (toProgram)
 
 
--- | Writes GLSL, without sharing
-toGLSL' :: Vec4 -> String
-toGLSL' v = unlines [ "void main() {"
-                    , "    gl_FragColor = " <> show v <> ";"
-                    , "}"
-                    ]
-
+-- Writes GLSL, without sharing
+-- toGLSL' :: Vec4 -> String
+-- toGLSL' v = unlines [ "void main() {"
+--                     , "    gl_FragColor = " <> show v <> ";"
+--                     , "}"
+--                     ]
 
--- | Writes GLSL, with sharing
-toGLSL :: Vec4 -> String
-toGLSL = show . toProgram . toMono
 
 
 -- | Pixel coordinates