Senior Ad Tech Specialist

Refinery89; Madrid; Remote; EUR 70,000 - 110,000; Part time

Benefits offered by this job

Remote within EU time zones

Health insurance coverage

International team

Job summary

Refinery89, a Dutch AdTech company with Madrid roots, seeks a Senior Ad Tech Specialist to own complex investigations across live publisher stacks. This is a remote, EU-time-zone, 6-month contractor role.

You will diagnose issues, reproduce problems, validate fixes, and translate findings into precise specifications for the Development team, with deep experience in Prebid.js, GAM, Amazon APS and consent frameworks.

Qualifications

• 5+ years in programmatic advertising technology and publisher monetization.
• Hands-on experience diagnosing and debugging live advertising environments.
• Deep knowledge of Prebid.js including configuration, adapters, and debugging.
• Ability to read bidder adapter source code when docs fall short.
• Strong knowledge of Google Ad Manager, line items, and AdX/dynamic allocation.
• Understanding of IAB TCF 2.x and GDPR consent mechanics across Prebid, GAM, and Amazon APS.
• Strong JavaScript skills for production tag reading/modification and validation.
• Professional English proficiency at C1/C2 level.
• Previous AdTech experience is mandatory.

Responsibilities

• Own complex technical issues from Operations or Development teams.
• Investigate tag defects, rendering failures, consent issues, and bid path problems.
• Reproduce issues using live publisher inventory and staging environments.
• Produce precise technical specifications or patched tag implementations for developers.
• Conduct live ad stack debugging using browser tools and Prebid debugging.
• Perform structured audits across Prebid, GAM, CMP/TCF, floor models, identity solutions.
• Monitor ecosystem changes and translate findings into actionable recommendations.
• Support phased rollouts with clear validation criteria and rollback plans.

Skills

AdTech expertise

Prebid.js

GAM knowledge

Consent frameworks

JavaScript debugging

English proficiency

Tools

Google Ad Manager

Amazon APS

Prebid.js

Consent frameworks (TCF)

ID frameworks (ID5/SharedID)

Job description

Senior Ad Tech Specialist (Temp)

Location: Remote, EU time zones

Team: Product / Development

Contract Type: Contractor

Contract Duration: 6 months, with possibility of extension

English Level: Professional fluency, C1/C2 mandatory

AdTech Experience: Mandatory

Reports to: CTO

IMPORTANT This is a temporary 6 month contractor position , with the possibility of extension depending on business needs and performance.

Professional English proficiency is mandatory for this role. Candidates must also have significant previous experience in programmatic AdTech . This is a senior position and is not suitable for candidates looking to transition into AdTech without prior industry experience.

About Refinery89

Refinery89 is a Dutch AdTech company headquartered in Madrid, working with premium publishers around the world to optimize their programmatic advertising performance.

Through advanced technology, data, and hands on technical support, we help publishers increase advertising revenue, improve efficiency, and gain greater transparency across their monetization stack.

Our international team operates at the intersection of technology, digital advertising, data, and publisher operations.

About The Role

We are looking for a Senior Ad Tech Specialist to join our Product and Development environment and take ownership of complex technical investigations across live publisher advertising stacks.

This is a deeply technical role focused on diagnosing issues, reproducing problems, identifying root causes, validating solutions, and translating findings into clear specifications or fixes that our Development team can act on.

You will work directly with live publisher environments, Prebid, Google Ad Manager, Amazon APS, consent frameworks, SSP integrations, browser debugging tools , and the wider programmatic ecosystem.

The objective is simple: when something is not behaving as expected, you should be able to determine what is happening, prove why it is happening, and define what needs to happen next.

The role also supports Product decisions, roadmap prioritization, and technical go or no go decisions with evidence from real publisher environments.

What You Will Do

Technical Support and Escalations

• Own complex technical issues that Operations or Development teams have been unable to resolve.
• Investigate tag defects, rendering failures, consent issues, bid path problems, and unexpected revenue behavior.
• Reproduce issues using live publisher inventory and controlled staging environments.
• Identify root causes and distinguish structural limitations from configuration problems that can be resolved.
• Produce clear technical specifications or patched tag implementations before handing work over to Development.

Live Ad Stack Debugging

• Investigate publisher implementations directly at browser level.
• Use Prebid debugging, network requests, browser consoles, HAR files, and consent string inspection to understand what is happening.
• Validate request ordering, consent propagation, and bidding behavior against the intended configuration.
• Confirm fixes in live environments before considering an issue resolved.

Ad Stack Audits

• Perform structured audits across publisher monetization stacks.
• Review areas including Prebid configuration, Google Ad Manager, Amazon APS, CMP and TCF implementation, floor models, ad units, identity solutions, video, SSP health, and bidder performance.
• Score findings and produce clear action plans prioritized by impact and severity.

Ecosystem Monitoring

• Track technical changes across Google, Amazon APS, Prebid.js, SSP partners, and the IAB Tech Lab.
• Assess how ecosystem changes may affect the Refinery89 stack and publisher implementations.
• Translate findings into clear technical recommendations.
• Escalate decisions when changes require Product or Development involvement.

Rollouts and Technical Validation

• Support phased technical rollouts using clearly defined success metrics.
• Establish validation criteria and rollback conditions.
• Test implementations in staging environments before Development handoff.
• Monitor performance following deployment and validate results against agreed thresholds.

Must Have Skills

• At least 5 years of experience in programmatic advertising technology, preferably within publisher monetization or the supply side.
• Significant hands on experience diagnosing and debugging live advertising environments.
• Deep working knowledge of Prebid.js, including configuration, adapters, modules, identity solutions, floors, and debugging.
• Ability to inspect and understand bidder adapter source code when documentation alone is insufficient.
• Strong technical knowledge of Google Ad Manager, including line items, pricing rules, AdX, dynamic allocation, GPT implementations, and MCM models.
• Strong understanding of IAB TCF 2.x and GDPR consent mechanics, including how consent is propagated across Prebid, GAM, and Amazon APS.
• Understanding of OpenRTB and supply chain transparency standards including ads.txt, sellers.json, and schain.
• Strong JavaScript knowledge, with the ability to read, modify, and validate production advertising tags.
• Advanced browser developer tools skills including network inspection, HAR analysis, and console debugging.
• Ability to write structured technical documentation that a developer can execute without requiring extensive additional explanation.
• Professional English proficiency at C1/C2 level.
• Previous professional experience in AdTech is mandatory.

THINGS THAT WILL HELP YOU STAND OUT

• Experience implementing or troubleshooting Amazon APS or TAM.
• Python or TypeScript experience for internal tooling.
• Experience with video advertising and outstream environments, including IMA SDK and VAST.
• Familiarity with identity solutions such as ID5, SharedID, UID2, or EUID.
• Experience working with Jira and Confluence.
• Previous exposure to LATAM or Dutch publisher markets.

What This Role Is Not

This is not a commercial partnerships or sales position.

You will not be responsible for commercial negotiations, SSP relationship ownership, or partner outreach.

This is also not a traditional campaign management or trafficking position. Day to day ad operations and GAM campaign trafficking are not the primary focus of the role.

Who This Role Is For

This role could be a strong fit if:

• You enjoy opening developer tools and understanding exactly what is happening behind an advertising implementation.
• When an issue cannot immediately be explained, your instinct is to investigate it methodically rather than guess.
• You are comfortable working across JavaScript, browser behavior, programmatic infrastructure, and publisher configurations.
• You can move between technical details and the larger business impact of an issue.
• You value evidence and reproducibility when making technical recommendations.
• You can clearly communicate complex findings to both technical and non technical colleagues.
• You are comfortable taking ownership of difficult problems that do not have an obvious answer.

INTERVIEW PROCESS

Our interview process consists of four stages.

• Initial Screening

A short introductory conversation with our recruitment team to understand your background, experience, English level, AdTech experience, and motivation.

• Technical Conversation

A live technical discussion based around a real Prebid or Google Ad Manager configuration .

• Written Technical Exercise

A practical exercise designed to assess how you investigate, document, and solve complex AdTech problems.

• Final Conversation

A final conversation with the CTO and relevant team members.

What We Offer

• Remote working within compatible EU time zones.
• A temporary 6 month contractor agreement with the possibility of extension.
• 50% coverage of the standard Sanitas private health insurance plan.
• The opportunity to work directly on complex publisher monetization environments and real world programmatic infrastructure.
• An international team working across AdTech, technology, data, and publisher operations.

JOIN REFINERY89

If you have spent years working inside programmatic advertising stacks, enjoy debugging the problems others cannot immediately solve, and want to work closer to Product and Development while remaining deeply connected to real publisher environments, we would love to hear from you.