diff --git a/playground/Main.hs b/playground/Main.hs
new file mode 100644
index 0000000000..3223d1e4f9
--- /dev/null
+++ b/playground/Main.hs
@@ -0,0 +1,116 @@
+module Main where
+
+import Protolude
+
+import Data.IORef (IORef, newIORef, writeIORef)
+import Language.PureScript.Externs ( ExternsFile )
+import Data.String (String)
+import Data.Map qualified as M
+import Language.PureScript.Make.Monad (readExternsFile)
+import System.FilePath.Glob qualified as Glob
+import Data.List qualified as L
+import System.Console.Haskeline (InputT, getInputLine, runInputT, defaultSettings)
+
+data ReplState = ReplState
+  { externsFiles :: IORef (Map FilePath (Maybe ExternsFile))
+  }
+
+mkReplState :: IO ReplState
+mkReplState = ReplState <$> newIORef mempty
+
+loadExterns :: (MonadIO m, MonadReader ReplState m) => [FilePath] -> m ()
+loadExterns files = do
+  liftIO $ putStrLn ("Loading externs..." :: String)
+  externs <- asks externsFiles
+  runExceptT (traverse readExternsFile files) >>= \case
+    Left _ ->
+      pure ()
+    Right !externFiles ->
+      liftIO $ writeIORef externs $ M.fromList $ L.zip files externFiles
+
+removeExterns :: (MonadIO m, MonadReader ReplState m) => m ()
+removeExterns = do
+  liftIO $ putStrLn ("Removing externs..." :: String)
+  externsFiles' <- asks externsFiles
+  liftIO $ writeIORef externsFiles' mempty
+
+loop :: [FilePath] -> InputT (ReaderT ReplState IO) ()
+loop files = do
+  i <- getInputLine "> "
+  case i of
+    Just "load" -> do
+      lift $ loadExterns files
+      loop files
+    Just "unload" -> do
+      lift removeExterns
+      loop files
+    Just "reload" -> do
+      lift removeExterns
+      lift $ loadExterns files
+      loop files
+    Just "delay" -> do
+      liftIO $ threadDelay 10000000
+      loop files
+    Just "exit" ->
+      pure ()
+    _ -> do
+      loop files
+
+data ReplState' = ReplState'
+  { externsFiles' :: Map FilePath (Maybe ExternsFile)
+  }
+
+defaultReplState' :: ReplState'
+defaultReplState' = ReplState' mempty
+
+loadExterns' :: (MonadIO m, MonadState ReplState' m) => [FilePath] -> m ()
+loadExterns' files = do
+  liftIO $ putStrLn ("Loading externs..." :: String)
+  runExceptT (traverse readExternsFile files) >>= \case
+    Left _ ->
+      pure ()
+    Right !externFiles ->
+      modify (\s -> s { externsFiles' = M.fromList $ L.zip files externFiles })
+
+removeExterns' :: (MonadIO m, MonadState ReplState' m) => m ()
+removeExterns' = do
+  liftIO $ putStrLn ("Removing externs..." :: String)
+  modify (\s -> s { externsFiles' = M.empty })
+
+loop' :: [FilePath] -> InputT (StateT ReplState' IO) ()
+loop' files = do
+  i <- getInputLine "> "
+  case i of
+    Just "load" -> do
+      lift $ loadExterns' files
+      loop' files
+    Just "unload" -> do
+      lift removeExterns'
+      loop' files
+    Just "reload" -> do
+      lift removeExterns'
+      lift $ loadExterns' files
+      loop' files
+    Just "delay" -> do
+      liftIO $ threadDelay 10000000
+      loop' files
+    Just "exit" ->
+      pure ()
+    _ -> do
+      loop' files
+
+
+main :: IO ()
+main = do
+  files <- Glob.glob "tmp/output/**/externs.cbor"
+
+  putStrLn ("Reader: " :: String)
+  _ <- do
+    replState <- mkReplState
+    flip runReaderT replState $ runInputT defaultSettings (loop files)
+
+  putStrLn ("State: " :: String)
+  _ <- do
+    flip evalStateT defaultReplState' $ runInputT defaultSettings (loop' files)
+
+  pure ()
diff --git a/purescript.cabal b/purescript.cabal
index 859126a658..261e61633c 100644
--- a/purescript.cabal
+++ b/purescript.cabal
@@ -428,6 +428,20 @@ executable purs
   autogen-modules:
     Paths_purescript
 
+executable playground
+  import: defaults
+  hs-source-dirs: playground
+  main-is: Main.hs
+  ghc-options:
+    -O2
+    -threaded
+    -fprof-auto
+    "-with-rtsopts=-hT"
+  build-depends:
+    Glob >=0.10.2 && <0.11,
+    haskeline >=0.8.2 && <0.9,
+    purescript
+
 test-suite tests
   import: defaults
   type: exitcode-stdio-1.0