Haskell environment setup 2026

Here are some tips to improve haskell experience in 2026.

Load all components when HLS starts:

// .vscode/settings.json
{
  "haskell.componentsLoading": "multi: whole-project",
}

Build all deps with haddock comments, so they appear in the hover popup:

-- ~/.cabal/config
program-default-options
  ghc-options: -haddock

Add a tasks.json to allow quick building with cmd+b:

{
    "version": "2.0.0",
    "tasks": [
        {
            "label": "cabal buil",
            "type": "shell",
            "command": "cabal build",
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "problemMatcher": []
        }
    ]
}

Set semantic tokens on for better highlighting:

"haskell.plugin.semanticTokens.globalOn": true