August 22, 2017

Jscrambler 101 — How to use the CLI

By Jscrambler | 4 min read

Jscrambler 101 — How to use the CLI

Last updated on October 24th, 2019

Welcome back to Jscrambler 101! A collection of tutorials on how to use Jscrambler to protect your JavaScript. These tutorials cover Jscrambler version 6.1.


Last time, we talked about Jscrambler’s Code Locks and how they could be used to protect your JavaScript and enforce licenses.

We’ve decided to take a step back from our transformations and show you a simple way to protect your code through our command line interface (CLI).

Let’s take a sample project:

Sample Project

Note that there’s a subfolder structure. Inside the js folder, we have a dontProtect.js file that we don’t want to protect with Jscrambler, but we do want to protect the clock.js and the index.html files.

Ignore files

We’ll start by creating a .jscramblerignore file in order to ignore the dontProtect.js file.

The .jscramblerignore file must be placed at the root of your project. The level where you should place this file depends on how you plan to zip your project.

If you will zip the project from inside the sample project folder, the .jscramblerignore file should be at the same level as index.html.

Jscrambler Ignore

As so, the .jscramblerignore file should include the following:


If you want to include the sample project folder in your zip file, then the .jscramblerignore file should be at the same level as this folder.

Jscrambler Ignore

In this case, the .jscramblerignore file should have the following:

sample project/js/dontProtect.js

You can also use .jscramblerignore for folders, and to include certain files in the protection process. For example:

#ignore all files in js folder
sample project/js/

#except for clock.js
!sample project/js/clock.js

Now, we’re ready to protect our application using the CLI.

Download jscrambler.json

First, we have to go to Jscrambler’s Dashboard and create an Application by clicking the Create App button.

Once you’re inside the app, select the Application Modes and the Transformations you want to apply (or select a template). Once that’s done, download your selections to a jscrambler.json file by clicking on the blue download icon.

Download Set of Transformations

Installing the CLI

Let’s continue by installing the CLI through node’s package manager:

npm install -g jscrambler

Now let’s zip our project, and remember to include the .jscramblerignore file. For ease, we will place our jscrambler.json file next to our zip file, but they could be in different locations.

Ignore File Location

Now, open your terminal, and after navigating to the same folder where you have your zip and jscrambler.json file, run the following:

jscrambler -c jscrambler.json -o protected

This means that the will be protected and placed in the protected folder.

Protected Folder

Now, you can test if the protection worked correctly. If you open the dontProtect.js file, you’ll notice that no changes occurred in this file. All other JavaScript files which were not included in dontProtect.js will be protected.

You can find further information about the Jscrambler CLI options here.

Integrations with Frameworks and Libraries

In case you're using a specific JavaScript framework or library, see our integration tutorials below:


That’s it! Your project has been protected by Jscrambler. You can check out other options to protect your files here, and also check out our ignore files documentation.

Feel free to proceed to one of our other 101 Tutorials:

Enjoy your testing and start protecting your Applications ASAP! If you have any additional questions, feel free to contact us.

JscramblerThe leader in client-side Web security. With Jscrambler, JavaScript applications become self-defensive and capable of detecting and blocking client-side attacks like Magecart.
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