Intellij can't find java.net.http when compiling with Java 11

Will :

I'm trying to get one of my projects ready for Java 11 but for some reason Intellij can't find java.net.http. It isn't underlining it as not found in module-info.java like it would if I typed it wrong but when I try build the project I get the error below. I've tried reinstalling Intellij 2018.2.3 and uninstalling all other versions of Java. Any advice on how to get this working would be appreciated.

Error:

Information:java: Errors occurred while compiling module 'crawler'
Information:javac 11 was used to compile java sources
Information:15/09/2018 11:16 - Compilation completed with 1 error and 0 warnings in 636 ms
C:\Users\Will\IdeaProjects\crawler\src\module-info.java
Error:(2, 22) java: module not found: java.net.http

module-info.java:

module crawler {
    requires java.net.http;
}

Request.java:

package Request;

import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public class Request {
    public static void main(String[] args) throws IOException, InterruptedException {
        System.out.println("starting download");
        String body = HttpClient.newBuilder().build().send(HttpRequest.newBuilder().uri(URI.create("https://example.com")).build(), HttpResponse.BodyHandlers.ofString()).body();
        System.out.println("finished download:" + body);
    }
}

Structure:

crawler
    src
        Request
            Request.java
        module-info.java

Will :

I had the wrong project language level set. To use java.net.http you need it to be at least 11. To change the project language level see: https://www.jetbrains.com/help/idea/project-page.html

Hopefully this helps someone else out.