Installing CasperJs - a journey of pain

· June 8, 2015

My friends on twitter keeps telling my that CasperJs is great (“da bomb”) for end-to-end-testing. Since I’ve been doing a lot of that, in .NET I took a look and it looks great.

I thought to myself: “Let’s install it and play around. How hard can it be?” Well as it turns out… for me at least, the installing part was a pain.

I’m on OS X Yosemite and I had nothing but problems. Yesterday I got it to work. This is my story.

I started out from the CasperJs installation instructions, but soon ran into problems. Not with Casper but rather with:

The Phantom menace

CasperJs is, to my knowledge, just a wrapper around PhantomJS, a WebKit headless browser. So first we need to install that.

When you go to their website there’s actually no installation instructions (?) but rather instructions to download. This gives us a big old binary, unzipped, in the [path where you downloaded]/[name of zip]/bin/phantomjs.

At this point I felt a little bit stupid, since I wanted this to be globally available on my system. Like in a /bin-folder for my user or something.

As it turns out there is something like that. And it even has a good name, once you know where it is: /usr/bin.

Now we can just copy the file there:

$ cp ~/Downloads/phantomjs-2.0.0-macosx/bin/phantomjs /usr/bin

Restart your terminal (or wait till CasperJs is install) and now it works.

Yes yes … I know about Homebrew

You can also supposedly install PhantomJS via HomeBrew:

$ sudo brew update && brew install phantomjs

For example. For the life of me I couldn’t get this to work. I’m blaming Indonesian internet speed. But that’s an option. Should you for any other reason don’t wanna use HomeBrew you now have an option.


At this point it was much smoother. Installing CasperJs is a breeze and can be done with HomeBrew again. And it worked on the first try for me:

$ brew update
$ brew install casperjs 

On the second command you can add --devel to get the latests bits. I didn’t do that but you can.

Restart you terminal again and then try casperjs --version to see that it works.

Casper via npm

CasperJs is also installable via npm but I had problems getting that to play nicely. Most likely due to the messed up PhantomJs installations.

It’s just npm install casperjs -g to install it on your system.

Trying it out

Another, more fun, way to verify it is to write a small script. Like the example Casper provides, for example;

var casper = require('casper').create();

casper.start('', function() {

casper.thenOpen('', function() {

Of course, before that, you need to create a new directory and then npm init. I could not get it to work when I npm install casperjs so I gave up on that. Here’s the commands I ran.:

$ mkdir casperdemo && cd casperdemo
$ npm init
$ touch demo.js

In the demo.js file you enter the code above. And the you run it, of course, with node demo.js…. NO - that’s wrong.

You start the file with the casperjs demo.js command. Otherwise you will get an error like Error: Cannot find module 'casper', which kind of make sense since it’s not installed.

When we go casperjs demo.js it works!

Extra points - Nightmare

There’s a wrapper API around Casper that is called Nightmare. It looks nice.

That’s is just an npm package, so installing Nightmare is just going npm install nightmare --save-dev.

Show it fail… (which it did for me of course) … you can always try to reinstall phatomjs with sudo brew update && brew install phantomjs.

With Nightmare installed you can write very fluent looking code like this:

var Nightmare = require('nightmare');
new Nightmare()
    .type('input[title="Search"]', 'github nightmare')
    .run(function (err, nightmare) {
      if (err) return console.log(err);


All-in-all this is probably the worst installation experience I’ve had on the Os X as a developer. I don’t know why, more often it’s super smooth. This was a lot of hick-ups. Now it works.

And CasperJs (and Nightmare) looks great.

Twitter, Facebook