Javascript/Node.js in PayPal

Aayushi Shah
2 min readAug 12, 2021


JavaScript or Node.js in particular, have long been praised for the high performance, rapid development, easy customization and dynamic perks it adds in the field of web and app development. The Node.js framework has come up as a preferred choice for various businesses requiring high-performance customer-facing apps and business websites. Owing to the various perks of Node.js web application development, the framework is recently employed by various organisations like NASA, Netflix, GoDaddy and PayPal, etc.

So we are taking about PayPal

PayPal has obviously been using JavaScript on the front end of their website for a long time, but that’s only the beginning.


According to Jeff Harrell, the development team at PayPal was previously divided into two segments – One who code on the browser side, while the other used to code on the server or application layer. The coding on the browser side was done in HTML, CSS, and JavaScript, while the coding on the application layer was done using Java. This practice according to him was too old school and was hindering the productivity of the developers along with the performance of the application.


Targeting the above problem, Node.js the framework of javascript was chosen as a preferred solution as it allows the developers to write code in JavaScript on both the browser and server side, thus enhancing their productivity. Moreover, the modular design of Node.js also helps the developers to meet the user requirements in an agile and flexible manner. This was a contrast to the monolithic application development process of Java.

The online payment giant was one of the earliest adopters of NodeJS. During an overhaul of their account overview page, they decided to try building the page in Node at the same time as their usual Java development. The NodeJS version worked out so well, that they chose to use it in production and build all client-facing applications in Node going forward. That means that most of what you see in your account is running on Node.


Node.js Application witnessed more than double the requests per second as compared to the Java application.

Node.js App featured 35% lower response time as compared to the Java app.

Node.js pages were served 200ms faster than the Java based application.

Impressed by the performance, rapid development, ubiquity, and high flexibility perks of the Node.js framework, PayPal has actively migrated to Node.js development. Almost all customer facing web applications of PayPal are now based on Node.js development framework and Jeff Harrell recommends Node.js for your web or app development requirements.

PayPal even went as far as to create and maintain their own version of Express, called KrakenJS. It’s pretty obvious that they like JavaScript over at PayPal.