Senior Software Engineer; opens tab

Position: Senior Software Engineer (opens in new tab)
# Senior Software Engineer New York, NY (Hybrid) or US Remote — excluding California•$160,000 - $180,000### Job Title Senior Software Engineer### Location New York, NY (Hybrid) or US Remote — excluding California### Salary Range $160,000 - $180,000###

Job Description SENIOR BACKEND ENGINEER — GO & PYTHON Real-time bidding / programmatic advertising

Remote (US, excluding California) or hybrid in NYC · $160,000–$180,000 + equityTHE OPPORTUNITY Our client is an established AdTech company in the content-to-commerce space. Their platform sits between brands, retailers and a large network of publishers, reaching shoppers at the point where they're deciding what to buy. It's a real programmatic stack — ad serving, OpenRTB, SSP and DSP integrations, auctions, identity and signal flows — running across roughly 45 services and processing millions of people's data every day at high throughput and high load.

They're in an expansion phase: building out the publisher network, adding retail media partnerships, and planning to double and triple the traffic through the platform. This role is on the core ad platform team.

THE ROLE You'd lead backend architecture and strategic engineering initiatives across the programmatic platform. In practice that means three things.

First, ownership of complex projects end to end — concept through production, balancing scalability, reliability, performance and maintainability, with the autonomy to make the calls.

Second, being the subject-matter expert on programmatic. You'd design and troubleshoot integrations with SSPs, DSPs, exchanges and other external advertising platforms, and translate industry standards and emerging protocols into engineering decisions. You'd be expected to trace the end-to-end lifecycle of an ad opportunity across both their systems and their partners', and to optimise it.

Third, raising the technical bar — mentoring backend engineers, running rigorous code review, and identifying architectural improvements and performance work before anyone asks for it.

A significant live workstream is migrating high-traffic services from Python to Go for performance.

WHAT THEY NEEDHard requirements:
• 7+ years of professional backend software engineering, at the top of the senior band. This is a role for someone who can hit the ground running.
• 2+ years working directly on programmatic advertising systems — SSPs, DSPs, ad exchanges, ad servers or header bidding solutions.
• Production Go and production Python. Both.
• Hands-on real-time bidding:
OpenRTB and auction mechanics, including bid request/response flows, timeouts, floor pricing and deal types.

Strongly wanted:
• Applied knowledge of the AdTech ecosystem — identity and cookie synchronisation, audience targeting, measurement, the full lifecycle of an ad request
• Proven design and operation of high-throughput, latency-sensitive distributed systems at scale, with strong instincts for service boundaries, API design, asynchronous processing and failure modes
• A track record of improving performance and reliability through instrumentation, monitoring, load testing and analysis
• Experience integrating complex external partners, with attention to versioning, data inconsistencies and graceful degradation
• Docker, Kubernetes and microservice architecture
• Cloud development. They run on GCP, but they're flexible — any major cloud is fine as long as you understand cloud development
• Well-rounded fundamentals: databases, networking, latency
• Experience leading major initiatives from architecture through delivery, including influencing roadmaps and driving cross-team alignment
• The ability to connect engineering decisions to business outcomes — revenue, ad delivery, reach — and to communicate with product and…