JavaScript Developer (REF: GOL)

Barcelona, Full time

Who we are:

Marfeel is a publishing platform that revolutionizes the way publishers create, optimize and monetize mobile websites. Over 850 publishers, including USAToday, Euronews, and El Confidencial use Marfeel to serve a billion mobile sessions, every month. 

We take a Technology-First approach and have a commitment to developing new tools for digital publishers to reach their audience. Our innovative technology, including PWAs, SEO and engagement tools, monetization and experimentation makes us proud of what we can offer to our clients: faster speeds, greater performance, and worldwide distribution.

Our team now has more than 190 members, made up of over 30 different nationalities. With headquarters in Barcelona and offices in New York and Bogotá, our people and our diversity are the reason behind our world-class product, and we’re still growing. 

Certified Google Publishing Partner


You will be working in the Go-Lives Team and you will be responsible for the technical implementations in order to onboard new customers into Marfeel. Working with both internal and external parties to ensure that client requests are handled quickly and appropriately (Sales Team, Engineers and CS), you will actively contribute to the on-going success of our solution. Together with our teams, you will help to identify, troubleshoot, and resolve technical needs experienced by our publisher and partner base.


 If you are a team-player, passionate about JavaScript and want to be a part of the Marfeel revolution, then we want to hear from you!


This is you:

  • Your life begins and ends with a slash.

  • You feel like you have a mission, not just a task, and you write testable front-end code in JavaScript and HTML/CSS.

  • You understand iterative development and a day without pushing code makes you sad.

  • You’re not afraid to crack open an existing code base and bend it to your will.

  • “Self Starter” is your middle name. You can take or come up with a high-level idea and run with it.

  • You understand how the web works, and you know how to optimize a website for performance.

  • You can’t imagine your life without a whiteboard, open-source boards and definitely CODE.

  • You know the importance of being part of a universe where all the departments need each other and work together for a mutual goal. So, your communication shows both tech and functional command of what you’re doing.

  • As a software craftsperson you will advocate and practice pair-programming, unit testing, refactoring, collective-code ownership and continuous integration.

  • You always leave the code better than you found it (Boyscout rule)

  • You are eager for knowledge.

  • You are a team player, you enjoy having technical discussions, and you are eager to share knowledge and coding best practices with your teammates.

  • You care about online news and user experience.

  • You have lots of stamina and you get bored if you have nothing to do.

  • You are hands-on and proactive.

  • You have a high level of English (this is a must).


  • You can solve technical problems equally well with OO, DOM oriented, or functional JS.

  • You have the ability to create an interface using JavaScript, HTML and CSS.

  • You have a solid understanding of the web technology stack (i.e. headers, cookies, cross-domain restrictions, https, caching, optimization opportunities, hardware acceleration, junk and scroll performance, etc.).

  • You have >1 year experience building software that works at web scale.

  • You have demonstrable experience with cross-browser JS and CSS development.

  • You have experience with client-side site development in JS.

  • You have a solid understanding of HTML5 tags - functions and intent.

We will be impressed if:

  • You have experience with Webpack, SASS and Jasmine.

  • You have experience troubleshooting technical issues for external clients.

  • Java 

  • Typescript 

  • Experience with metric systems like Google Analytics, Alexa, Comscore...

  • Experience with AdServing

  • Nginx, Tomcat, MongoDB.

This will be you as part of the Marfeel team:

  • Open-space, light-filled and eco-conscious office with large sunny terrace

  • Unlimited refreshments including coffee, tea & soft drinks

  • Subsidized healthy & tasty lunch delivered to the office & free fresh fruit 

  • Ping-pong, video games, table football and other games for down-time

  • Free language and yoga classes at the office

  • Subsidized monthly plan to a huge network of health & wellness centres (Andjoy)

  • Transport, restaurant & kindergarten tickets

  • Subsidized health insurance for you and your partner/family

  • Flexible working hours and early finish on Fridays

  • Loyalty sabbatical and vacation days

  • Access to training platforms, courses & materials

  • Referral bonus for talent brought to us by you

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