I'm using Emacs (26.3) and org-mode (9.3.6) and I seem to have two different versions of ghci going, depending on whether I'm using haskell-mode alone with a *.hs file, or whether I am evaluating an org-mode babel code block. If I open, say, test.hs in Emacs, haskell-mode starts up. And if I choose <Start interpreter> from the menu, I get this "lambda prompt" REPL The next big Haskell project is about to start! If I break, you can: 1. Restart: M-x haskell-process-restart 2. Configure logging: C-h v haskell-process-log (useful for debugging) 3. General config: M-x customize-mode 4. Hide these tips: C-h v haskell-process-show-debug-tips λ> But if I call M-run-haskell, I get this "Prelude prompt" REPL Configuring GHCi with the following packages: GHCi, version 8.6.5: http://www.haskell.org/ghc/ :? for help Loaded GHCi configuration from /home/lawrence/.ghc/ghci.conf Prelude> Prelude> and this babel bit knows and interacts with it #+BEGIN_SRC haskell :results output :set +m doubleMe x = x + x doubleUs x y = doubleMe x + doubleMe y #+END_SRC but then trying to run this code block with lambda prompt REPL, I get the error executing Haskell code block... org-babel-execute:haskell: Buffer *haskell* does not exist or has no process even though the lambda REPL is called *haskell*. Why am I getting two separate REPLs? BTW, which IDE do Haskell big boys and girls use? LB