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+31 654 655 280
+34 605 202 070

Software Engineer Ad-tech (Back-end)

At Refinery89 we help publishers significantly boost the quality, quantity, innovation and distribution of their ad-inventory in the increasingly complex digital ecosystem. Our main objective: increase their net outcome. Besides our deep expertise the backbone of our success is our award winning and header bidding technology which provides our publishers with a competitive advantage. At the same time we deliver our publishers exceptional service with speed and share our passion for online advertising technology, making sure collaborating with us is a pleasure.

The online ad-industry has been driven by advertisers for years, at Refinery89 we challenge this standard by always working and thinking from a publisher first approach and giving publishers the best possible monetization solutions and service available.

We operate from our offices in Madrid and Amsterdam and make sure we always add value between digital publishers and advertisers. As a team we strive for perfection and profitable results through innovation, speed and exceptional service in all our activities, while we question assumptions, keep learning and make sure we enjoy every day at the office!


Madrid, Ponzano

Employment Type:


Hours per week:


Seniority Level

Medior / Senior level

What are we looking for?

The ad-tech software engineer will be responsible for managing and executing our technology roadmap. You will continue to develop and optimize our header bidding technology and supporting systems. The ideal candidate has proven experience with the development of and integration with, advertising technology and a curiosity about digital advertising.

To continue our exponential growth, the tasks of the Software Engineer will vary but generally include:

  • Developing new technologies and add-ons to support our ad-technology
  • Bringing structure to the software and development process (introduce new methodologies, workflows, software quality assurance procedures etc.)
  • Optimizing and improving our header bidding technology and related systems
  • Improve our publisher dashboard integrations and offering
  • Managing and developing API integrations with various external partners
  • Implementing features and components in response to client and colleague feedback
  • Work on the development roadmap
  • Bug fixing
  • A/B testing
  • Process automation
  • Make sure the software is in good hands by writing, running and automating tests
  • Write code documentation
  • Update old frameworks and languages to newer versions
  • Collaborate with the team to develop amazing services from design to production
  • Stay up-to-date on new technologies and architectures and eventually look for ways to implement them into our current software engineering process

We are looking for an energetic and pro-active person with relevant experience that is readily available in Madrid or willing to relocate. You can work independently, do not mind to be flexible in working hours and are analytical. The team language is English so a high level is desirable.

Our goal is to create a small team of exceptional people with positive mindsets and a natural drive to bring the best service to our clients and partners, while going all out to maintain the company’s exponential growth.

What we expect from you:

  • 5+ years of experience, ideally with advertising systems
  • Good programming abilities, testing your development is a second nature to you, and you are very mindful about your application architecture, performance and maintainability and its overall quality
  • You love to code yourself, but are also open to help and steer other developers
  • Readiness to lead a team of developers in the future
  • Excellent collaboration and project management skills required
  • An appetite for back-end development
  • Strong problem solving skills
  • Strong attention to detail - accurate data gathering, insightful analysis, ability to handle tactical details with detailed execution
  • Ability to quickly learn new technology and translate the features of a range of products into business benefits
  • High level of English, you can passively follow conversations from your colleagues and don't miss anything that is discussed at the office
  • Must have the ability to work autonomously


  • Developing integrations for Prebid.org Header Bidding or GAM
  • Basic knowledge and understanding of digital advertising ecosystem and technologies or ability to catch up quickly
  • Setting up API integrations for data processing
  • Experience with in-app advertising solutions (Pre Bid and Ad Manager SDK’s)
  • Experience with video ad-tech solutions
  • Large-scale distributed systems, service oriented architecture
  • Experience in caching system (in memory, distributed)
  • Knowledge of the JVM (GC, Concurrency...)
  • Experience in high performance and/or low latency system
  • Messaging middleware (Kafka, RabbitMQ...)
  • MySQL and NoSQL datastores
  • Good knowledge of digital media metrics and KPI's
  • Coding experience with: Laravel framework, Git, AWS Lambda, NodeJS, Javascript
  • Experience with Google Data Studio integrations
  • Interest in technology and digital advertising

What can you expect from us?

If you’re looking to make an impact, R89 is the right place. We offer an exceptional and flexible work environment. Being a startup with exponential growth nearing scale-up phase, those willing to go the extra mile will be able to boost both their personal and professional lives.

You will work in collaboration with our CTO in Amsterdam and colleagues in the Madrid office and remotely and be part of a team of people who are committed to helping each other grow.

  • Immediate start
  • Competitive compensation and benefits (holidays, equipment, yearly team weekend)
  • Additional yearly bonus upon hitting company wide turnover en profit targets
  • Flexible hours and remote working options
  • Hands-on advanced training in digital advertising
  • Be part of an experienced team of international professionals
  • Career growth opportunities; current hires are future execs.
  • Flexible office with terrace, bbq's, including free coffee and weekly afternoon drinks!

You have the drive to be exceptional and deliver the best results every single day!

Sound like you? Send your application (in English) to careers@refinery89.com including an elaborate motivation and CV. Please include the job title in the subject of your e-mail.

Note: Working at Refinery89 requires you to be fluent in English verbally.

let's connect!

+31 654 655 280
+34 681 026 725
+33 756 925 805
+39 345 335 6428