Senior Software Engineer (HTML, JS, CSS, RestFul APIs), Emerging Technologies

Emerging Technology Spain, Spain


For over 10 years, Zscaler has been disrupting and transforming the security industry. Our 100% purpose-built cloud platform delivers the entire gateway security stack as a service through 150 global data centers to securely connect users to their applications, regardless of device, location, or network in over 185 countries protecting over 3,500 companies and 100 million threats detected daily.
We work in a fast paced, dynamic and make it happen culture. Our people are some of the brightest and passionate in the industry that thrive on being the first to solve problems.  We are always looking to hire highly passionate, collaborative and humble people that want to make a difference. 

Senior Software Engineer  (HTML, JS, CSS, RestFul APIs), Emerging Technologies
Location: Valencia, Spain

We have a terrific opportunity in our Zscaler Isolation Platform team for a Senior Software Engineer. This is an excellent opportunity to join a small, dynamic team that is working on cutting edge Isolation Browser technology to evolve our current cloud security flagship products: ZIA and ZPA.

The Senior Software Engineer (HTML, JS, CSS, RESTful APIs) will report to the Sr. Director, Software Engineering. Zscaler is looking for a seasoned and agile Engineer that has a unique combination of skills.

The ideal candidate
will play a key role in architecting, developing and maintaining the Isolation Experience for our Browser Isolation technology. This is a key component of our overall platform as this is the most important customer facing piece of the Isolation technology and needs to be fast, reliable and delight our customers. The primary focus of our Isolation Experience is to deliver security to the end user by making sure that nothing bad from the web can affect the user’s endpoint and no confidential data from cloud applications is left behind on unmanaged, untrusted endpoints.

About the Team

The Isolation Platform is a small distributed team that works fast and lives on the cutting edge of software engineering in backend, frontend and infrastructure. We like open-source but we are not afraid of building stuff ourselves where it makes sense and we can optimize something. Our philosophy is: done is better than perfect and we strive to work iteratively and optimize our processes along the way so that we can achieve reliable and fast product deliverables that delight our customers.

The environment is fast-paced and requires the ability to take initiative and manage ambiguity to drive effective results. This role may interface with architects, subject matter experts, product managers, other developers and QA engineers located globally and in different time zones.
Responsibilities/What You’ll Do
  • Design and implement functionality using different web-related frameworks to build beautiful and effective User Experiences
  • Maintain and enhance our browser isolation technology to help protect against bad web content getting into the user’s devices and making sure that good data (confidential) does not stay behind on third party computers
  • Demonstrate the ability to build software in small, interactive chunks and perform the unit testing prior to handing over to the quality assurance team
  • Integrate the Isolation Experience in a microservice based architecture that is distributed and highly scalable
  • To work cross-functionally with the Quality Assurance team to test the work product, and influence the testing to make the product ready for deployment
  • Focus on rendering performance in order to ensure superior experience for a heavy interaction platform.
Qualifications/Your Background
  • Demonstrable experience of software development experience and proven experience with Frontend related technologies and tools and technologies like HTML5, CSS, JS, Angular, React.js, service workers, PWA, JQuery, Bootstrap etc. Experience with html5 canvas and graphical programming is a plus.
  • Full stack development experience with an emphasis on front-end client technologies.
  • Familiarity with implementing services following REST model and microservices architecture
  • Excellent knowledge of technologies like websocket and webrtc.
  • Knowledge of either nw.js or electron frameworks is considered a plus.
  • Knowledge of Chrome API or chrome internals (renderer, v8 engine etc), extensions API is a big plus
  • Familiarity with Node.js or other async programming framework
  • Working knowledge of cloud infrastructure services on AWS/Azure is a plus.
  • Working knowledge of Linux system
  • Pleasant to work with, passion for solving customer problems with a can-do attitude
  • Excellent Problem Solving skills


Additional information about Zscaler (NASDAQ : ZS ) is available at


Zscaler is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees.


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