Senior Software Engineer - User Trail 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

The User Trail team owns the analytics and observability platform that captures how people actually use The Trade Desk's products — things like page views, clicks, and other interactions across our core web applications. This event data flows into our data platform and powers everything from product analytics to an AI-powered internal tool our team built, which lets people across the company investigate what happened in the platform in plain language instead of digging through logs by hand. That tool has become a genuine business asset: it's helped support and trading teams give clients clear, evidence-backed answers about what happened in their accounts, and we're actively extending access so teams beyond engineering — including business and commercial teams — can explore this data themselves without needing to write a query. We work closely with teams across the company to make sure the right signals are captured and easy to query. It's a small, high-leverage team: the data we ship underpins troubleshooting and decision-making for a wide range of teams, so the quality and reliability of our pipelines and tools matter a lot.

What you’ll do:

• Build and improve the tools that let people across the company — not just engineers — find answers in our data themselves, from self-service dashboards to the AI-powered assistant our team built.
• Own end-to-end delivery of significant features in our event tracking and data platform, from design through rollout, with an eye toward making the data more accessible and useful to teams outside engineering.
• Help extend safe, well-governed access to more parts of the company, working through the tradeoffs of who should see what and how self-service should work.
• Act as a go-to expert for one or more parts of the system (e.g. the client-side SDKs, the ingestion pipeline, or the data warehouse layer), providing technical guidance to engineers on and off the team.
• Partner directly with the teams building on top of our data — support, trading, business, and product — to understand what questions they need answered and translate that into tools and features.
• Raise the bar on quality and testing practices for the team, and mentor other engineers through code review, design discussions, and pairing.
• Contribute to technical design decisions and help define how the team's tools and processes evolve as more of the company comes to depend on them.

Who you are:

Our culture is much deeper than just having fun together (though, we do that well too...). We take pride in our engineers being trust-builders, generous givers, scrappy problem solvers, and gritty pursuers of excellence. You do not have to meet all the requirements below, but we believe that people who meet most of them will have a higher likelihood of succeeding in this role.

• You have deep, hands-on experience building and operating backend services or data pipelines at scale, and you're comfortable owning a project from design through production.
• You have experience with (or a strong interest in quickly ramping up on) tools like modern data warehouse/lakehouse platforms, event-driven pipelines, or SDK development for client applications.
• You communicate clearly with both engineers and non-technical stakeholders, and you're comfortable being the person others turn to for guidance in your area of expertise.
• You care about the reliability and correctness of the systems you build — you think about edge cases, monitoring, and failure modes, not just the happy path.
• You collaborate well across teams and disciplines, and you take an active role in making the people around you better through mentorship and code review.
• You're energized by ambiguity — you're comfortable taking a loosely defined problem and turning it into a concrete, well-scoped plan.

Variety of technical opportunity 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 don't need engineers who know all the answers; we need engineers who can invent the answers no one has thought of yet, to the questions yet to be asked.