About Smart Working
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About the Role
As a Senior AdTech Engineer, you will take a senior, guiding role in the continued evolution of a proprietary programmatic advertising platform, now on version 3 and live in production. The platform is continuously evolving, with a focus on performance, reliability and proprietary agentic processes for media buying.
This is a back-end-heavy software engineering role, estimated at an 80/20 back-end/front-end split. You will own a critical area independently while collaborating day to day with a data scientist and guiding the engineering team. You will work alongside the CTO, combining hands-on engineering with architectural judgement and technical leadership.
Responsibilities
Build and scale the back-end components and infrastructure behind a programmatic advertising platform, developing low-latency, high-throughput services that process ad requests in milliseconds.
Build proprietary AI agents for buying and distributing media, working closely with the team’s data scientist on content tagging and enrichment of ad requests.
Integrate with third-party AdTech platforms and APIs, including OpenRTB, DSPs and SSPs.
Act as a senior engineer within the team, overseeing work, running code and peer reviews, and guiding other engineers.
Own a critical area independently while collaborating closely with the data scientist and guiding the wider engineering team.
Apply architectural judgement and attention to detail in a real-time bidding environment where milliseconds and correctness matter.
Help shape how agentic processes fit into the platform.
Work flexibly within solid engineering disciplines, including GitOps deployments and a code-review culture.
Take a problem-solving approach to building proprietary technology rather than simply following a specification.
Prioritise careful improvement of a live, performance-critical platform without breaking existing functionality.
Own the design and delivery of services or components end to end.
Guide engineers through code reviews, mentoring and setting technical standards; line management is not required.
Requirements
5+ years of advanced Node.js back-end engineering experience.
3+ years of advanced experience building low-latency, high-throughput systems requiring millisecond response times and handling high request volumes. Relevant experience may include fintech, trading, payments, banking platforms, or real-time gaming or betting back-ends.
1+ year of proficient, hands-on experience building agentic AI for production, including LLM agents and working with a data scientist on models. You must have built AI agents, rather than simply used AI tools.
5+ years of advanced experience building APIs and third-party integrations.
2+ years of experience conducting code reviews and peer reviews and guiding engineers, or equivalent experience as a senior individual contributor who formally mentors engineers and owns review standards.
3+ years of advanced TypeScript experience. Strong modern JavaScript experience can be considered as a substitute.
2+ years of working experience with React.
2+ years of working experience with Google Cloud Platform (GCP). AWS or Azure experience can be considered as a substitute.
2+ years of working experience with Kubernetes and Argo CD for GitOps deployments. Kubernetes with Flux or Helm can be considered as a substitute.
Senior Engineer/Architect-level capability with technical leadership experience and the ability to work alongside the CTO.
Nice to Have
2+ years of programmatic advertising experience, including OpenRTB, real-time bidding, DSPs and/or SSPs. Strong senior engineers with relevant low-latency systems experience may still be considered, as the domain terminology can be learned.
Experience leading a project and owning the design and delivery of a service or component end to end.
Basic Golang experience. Rust, Java, C++ or another performance-focused language can be considered as an alternative.
1+ year of working experience with Jenkins for CI/CD. GitHub Actions, GitLab CI or CircleCI can be considered as alternatives.
1+ year of working experience with Grafana for monitoring. Prometheus, Datadog or New Relic can be considered as alternatives.