Senior Software Engineer – Janus Platform in London

The Trade Desk is a global technology company and the world’s leading independent platform for digital advertising, with nearly 4,000 employees across more than 30 offices. Our technology helps advertisers reach the right audiences across the open internet — from streaming TV and podcasts to mobile apps, news, and more. Advertising powers the content people love. By making it more transparent, effective, and responsible, we help support trusted journalism, quality entertainment, and creators worldwide. The world’s brands and agencies rely on us to reach their customers and grow their businesses responsibly.

The scale of our platform brings unique technical challenges — from processing massive datasets in real time to building systems that operate reliably on a global scale. When you work here, your impact is worldwide. We welcome diverse perspectives, encourage curiosity, and build teams that learn from one another. If you’re driven to solve meaningful challenges, we’d love to meet you.

What we do

Janus is The Trade Desk's internal feature release platform — the engine behind how every product change reaches clients, from Alpha to General Availability. Our team owns the full stack of a high‑availability system that integrates with hundreds of internal services and propagates config changes in near real‑time. We shape how cross‑functional teams across the company execute go‑to‑market, building workflows that let teams act independently and keep every feature launch on track. We hold engineering practices to a high standard and value people who are self‑driven, take measured risks, and are motivated to help those around them.

What you’ll do

• Own the design, development, and evolution of the Janus platform end‑to‑end, from frontend workflows to backend infrastructure.
• Build self‑service tooling that empowers cross‑functional teams to act independently and reduce bottlenecks in the feature launch process.
• Ensure platform reliability at scale: high availability, high‑volume traffic handling, and near real‑time config propagation across hundreds of integrated services.
• Collaborate closely with stakeholders across the company to translate loosely defined requirements into reliable, well‑engineered solutions.
• Drive architectural decisions and set engineering quality standards for the team.
• Contribute to a culture of good engineering practices, code quality, and knowledge sharing.

Who you are

• Experienced building platform services, internal tooling, or developer infrastructure.
• Skilled in distributed systems — you understand the trade‑offs behind availability, consistency, and low‑latency data propagation.
• Comfortable navigating ambiguity — you can make progress with loosely defined requirements and multiple stakeholders.
• Thoughtful about user experience — you think from the end user’s perspective and can craft workflows that feel intuitive to non‑technical users.
• Self‑driven — you take ownership, set your own direction, and follow through without close oversight.
• Collaborative — you actively help teammates grow and succeed, not just deliver your own work.
• Willing to take measured risks and advocate for decisions even when the path isn’t fully clear.

A variety of technical opportunities is one of the best things about working at The Trade Desk as a software engineer, which is why we do not expect you to know every technology we use when you start. What we care about is that you can learn quickly and find solutions to complex problems using the optimum tools for the job. What you know is less important than how well you learn and innovate. We are not seeking engineers who know all the answers; we need engineers who can invent answers no one has thought of yet and find answers to the questions yet to be asked.

The Trade Desk is an equal opportunity employer. All aspects of employment will be based on merit, competence, performance, and business needs. We do not discriminate on the basis of race, color, religion, marital status, age, national origin, ancestry, physical or mental disability, medical condition, pregnancy, genetic information, gender, sexual orientation, gender identity or expression, veteran status, or any other status protected under federal, state, or local law. As an Equal Opportunity Employer, The Trade Desk is committed to creating an inclusive hiring experience where everyone has the opportunity to thrive.