I've created a minimal example to show you what I've tried. Below is also a truncated error log. Could someone help me figure out how to get ghci working with this example? https://github.com/mlitchard/reflex-todo stack repl --stack-yaml=stack-ghc.yaml Truncated error log Error: -- While building custom Setup.hs for package jsaddle-dom-0.9.2.0 using: /home/mlitchard/.stack/setup-exe-cache/x86_64-linux/Cabal-simple_mPHDZzAJ_1.24.2.0_ghc-8.0.2 --builddir=.stack-work/dist/x86_64-linux/Cabal-1.24.2.0 build lib:jsaddle-dom --ghc-options " -ddump-hi -ddump-to-file" Process exited with code: ExitFailure 1 Logs have been written to: /home/mlitchard/projects/git/reflex-todo/.stack-work/logs/jsaddle-dom-0.9.2.0.log Preprocessing library jsaddle-dom-0.9.2.0... [587 of 599] Compiling JSDOM.Custom.XMLHttpRequest ( src/JSDOM/Custom/XMLHttpRequest.hs, .stack-work/dist/x86_64-linux/Cabal-1.24.2.0/build/JSDOM/Custom/XMLHttpRequest.o ) /home/mlitchard/projects/git/reflex-todo/.stack-work/downloaded/Vheiln5kqwE0/src/JSDOM/Custom/XMLHttpRequest.hs:39:46: error: • Could not deduce (Control.Monad.Catch.MonadThrow Language.Javascript.JSaddle.Types.JSM) arising from a use of ‘throwM’ from the context: MonadDOM m bound by the type signature for: throwXHRError :: MonadDOM m => Maybe XHRError -> m () at src/JSDOM/Custom/XMLHttpRequest.hs:38:1-53 • In the second argument of ‘(.)’, namely ‘throwM’ In the second argument of ‘maybe’, namely ‘(liftDOM . throwM)’ In the expression: maybe (return ()) (liftDOM . throwM) /home/mlitchard/projects/git/reflex-todo/.stack-work/downloaded/Vheiln5kqwE0/src/JSDOM/Custom/XMLHttpRequest.hs:42:20: error: • No instance for (Control.Monad.Catch.MonadMask Language.Javascript.JSaddle.Types.JSM) arising from a use of ‘bracket’ • In the first argument of ‘(.)’, namely ‘bracket aquire id’ In the expression: bracket aquire id . const In an equation for ‘withEvent’: withEvent aquire = bracket aquire id . const /home/mlitchard/projects/git/reflex-todo/.stack-work/downloaded/Vheiln5kqwE0/src/JSDOM/Custom/XMLHttpRequest.hs:45:31: error: • Could not deduce (Control.Monad.Catch.MonadCatch Language.Javascript.JSaddle.Types.JSM) arising from an operator section from the context: MonadDOM m bound by the type signature for: send' :: MonadDOM m => XMLHttpRequest -> Maybe JSVal -> m () at src/JSDOM/Custom/XMLHttpRequest.hs:44:1-62 • In the expression: (`onException` abort self) In the second argument of ‘($)’, namely ‘(`onException` abort self) $ do { result <- liftIO newEmptyMVar; r <- withEvent (onAsync self Generated.error . liftIO $ putMVar result (Just XHRError)) $ withEvent (onAsync self abortEvent . liftIO $ putMVar result (Just XHRAborted)) $ withEvent (onAsync self load . liftIO $ putMVar result Nothing) $ do { void $ case mbVal of { Nothing -> ... Just val -> ... }; liftIO $ takeMVar result }; throwXHRError r }’ In the expression: liftDOM $ (`onException` abort self) $ do { result <- liftIO newEmptyMVar; r <- withEvent (onAsync self Generated.error . liftIO $ putMVar result (Just XHRError)) $ withEvent (onAsync self abortEvent . liftIO $ putMVar result (Just XHRAborted)) $ withEvent (onAsync self load . liftIO $ putMVar result Nothing) $ do { void $ case mbVal of { Nothing -> ... Just val -> ... }; liftIO $ takeMVar result }; throwXHRError r }