diff --git a/package.json b/package.json
index 380403fb..e47a6bea 100644
--- a/package.json
+++ b/package.json
@@ -110,6 +110,13 @@
           "default": "off",
           "description": "Traces the communication between VSCode and the languageServerHaskell service."
         },
+        "languageServerHaskell.shakeThreads": {
+          "scope": "machine",
+          "type": ["integer", "null"],
+          "default": null,
+          "description":
+            "The number of Shake threads to use in ghcide or haskell-language-server. Leave empty for single threaded, or 0 for automatic."
+        },
         "languageServerHaskell.logFile": {
           "scope": "resource",
           "type": "string",
diff --git a/src/extension.ts b/src/extension.ts
index ed36843a..8db2f05e 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -159,7 +159,7 @@ function activateHieNoCheck(context: ExtensionContext, folder: WorkspaceFolder,
   // be absolute.
   const serverPath = hieLaunchScript;
 
-  const runArgs: string[] = ['--lsp'];
+  let runArgs: string[] = ['--lsp'];
   let debugArgs: string[] = ['--lsp'];
 
   // ghcide does not accept -d and -l params
@@ -172,6 +172,14 @@ function activateHieNoCheck(context: ExtensionContext, folder: WorkspaceFolder,
       debugArgs = debugArgs.concat(['-l', logFile]);
     }
   }
+  if (hieVariant === 'ghcide' || hieVariant === 'haskell-language-server') {
+    const shakeThreads: number | null = workspace.getConfiguration('languageServerHaskell', uri).shakeThreads;
+    if (shakeThreads !== null) {
+      const threadsArg = ['-j', shakeThreads.toString()];
+      runArgs = runArgs.concat(threadsArg);
+      debugArgs = debugArgs.concat(threadsArg);
+    }
+  }
 
   // If the extension is launched in debug mode then the debug server options are used,
   // otherwise the run options are used.