TypeScript support -- disabled by default

lib/pipeline/webpack.config.js

@@ -201,6 +201,21 @@ if (isFlowEnabled) {
   );
 }
 
+// TypeScript
+// -----------------------------------------------------------------------------
+
+// should be false in configs that have isFlowEnabled = true
+const isTypeScriptEnabled = false;
+if (isTypeScriptEnabled) {
+  // position @babel/preset-typescript as the last preset (runs first)
+  // see: https://blogs.msdn.microsoft.com/typescript/2018/08/27/typescript-and-babel-7/
+  baseBabelLoader.options.presets.push(
+    require.resolve('@babel/preset-typescript')
+  );
+  // additional extensions
+  base.resolve.extensions.push('.ts', '.tsx');
+}
+
 // development config
 // -----------------------------------------------------------------------------