hie-bios VS vscode-ghc-simple

You're likely going to have to set up a hie-bios file in an hie.yaml file. More info here: https://github.com/haskell/hie-bios

Look here: hie-bios (its the library used by haskell-language-server to get to know your project better, iirc).

Yeah the same happened to me with previous versions of the Haskell IDE Engine that used Stack, so I ended up with several snapshots under \~/.stack that took a lot of space. Nowadays I just install HLS, Cabal and a single HLS-supported GHC with ghcup. It's a huge difference. I think there is a Windows-supported equivalent of ghcup, but I have not used it. If you also have Stack installed, remember that you can place a [`hie.yaml`](https://github.com/mpickering/hie-bios#explicit-configuration) file in your project root that can [force HLS to use cabal](https://github.com/mpickering/hie-bios#cabal) instead of stack in your project (this was needed last time I checked, complex configurations would need tuning this file a bit, though).

You can provide an alternative stack.yaml to HLS, with the specific configuration for the ide, although you have to write down an explicit hie.yaml file, take a look to https://github.com/mpickering/hie-bios#stack

Please consider testing dev builds with the WIP new vgs-bios feature, inspired by the amazing hie-bios. It reads your project hie.yaml and supports multi-component/multi-package projects.

I created vscode-ghc-simple, which is a VSCode extension that provides editor tooling using only GHCi. It interacts with GHCi using text I/O, especially with the features that use :set +c to provide expression type information and go to definition.

Im not sure haskell language server works with reflex right now (haven't used reflex recently). You may ask on IRC or maybe try https://github.com/dramforever/vscode-ghc-simple (haven't used it recently either). For ghcid, I don't think it supports reloading across packages, you can try something like what I did here https://github.com/aveltras/blog-reflex/blob/master/blog-reflex.cabal (basically, having only one cabal file for the whole project and two executable client and server both having two source directories, so during development, you'd only work with ghcid on the server part, putting most of the code that can work on both environment in the common directory).