Update index.md (#24657)

docs/blog/2018-12-17-turning-the-static-dynamic/index.md

@@ -75,15 +75,18 @@ For more info or configuration options (e.g. in different branches and build env
 4. **Proxy the emulated functions for local development**: Head to `gatsby-config.js` and add this to your `module.exports`:
 
 ```jsx:title=gatsby-config.js
-var proxy = require("http-proxy-middleware")
+const { createProxyMiddleware } = require("http-proxy-middleware") //v1.x.x
+// Use implicit require for v0.x.x of 'http-proxy-middleware'
+// const proxy = require('http-proxy-middleware')
+// be sure to replace 'createProxyMiddleware' with 'proxy' where applicable
 
 module.exports = {
   // for avoiding CORS while developing Netlify Functions locally
   // read more: https://www.gatsbyjs.org/docs/api-proxy/#advanced-proxying
   developMiddleware: app => {
     app.use(
       "/.netlify/functions/",
-      proxy({
+      createProxyMiddleware({
         target: "http://localhost:9000",
         pathRewrite: {
           "/.netlify/functions/": "",