Staff Backend Engineer, Ads Recommender System

Unity; San Francisco (CA); On-site; USD 190,000 - 240,000; Full time

Benefits offered by this job

Comprehensive health insurance

Stock ownership

Generous vacation days

Employee assistance program

Job summary

Unity is seeking a Staff Backend Engineer to lead Offer Delivery, the backend service driving which offers players see in real time. You will define architecture, drive delivery, and oversee targeting, pacing, and supply-side rules across critical systems in a fast-growing ad/monetization platform.

You’ll work with Go and Java services, real-time bidding and direct placements, and collaborate with ML teams to push ranking improvements into production while mentoring across teams.

Qualifications

• Significant backend system ownership and delivery leadership.
• Experience in designing large-scale, latency-sensitive distributed services.
• Proficiency in Go or Java, with ability to adapt to Go quickly.
• Hands-on with observability platforms and data streaming technologies.
• Proven ability to design stable systems amid changing requirements.
• Experience mentoring engineers and driving cross-team initiatives.

Responsibilities

• Architect & design the architecture of Offer Delivery and lead critical initiatives.
• Build, test, and ship Go and Java services for real-time bidding and direct placements.
• Collaborate with ML team to bring ranking improvements to production, including feature retrieval and model serving.
• Lead across teams to align auction, ML, platform, and product decisions.
• Ensure high availability and reliability of production services, with on-call rotations.
• Mentor engineers and set engineering standards, modeling best practices.

Skills

Backend architecture

Distributed systems

Go

Java

Observability

Data streaming

Mentorship

Cross-team collaboration

Tools

gRPC

Job description

The opportunity

Offerwall by Unity is a leading mobile advertising and monetization platform that helps game developers maximize revenue and engage users through rewarded experiences. For over a decade, we've connected millions of players with offers that provide tangible in-app value, and we're now building the next generation of that product.

At the center of it is Offer Delivery, the backend service that decides which offer a player sees, when, and on what terms. It operates on two fronts: bidding in real time as a DSP into multiformat fullscreen auctions, and retrieves input features, calls our ML ranking models, and applies targeting, pacing, and supply-side rules to choose what offers gets shown.

We're seeking a Staff Backend Engineer to be the technical leader for Offer Delivery. You will set the technical vision, define the architecture, influence the roadmap, and drive delivery, owning how targeting, pacing, and supply-side rules are enforced on the serving path.

This is a meaningful role at the intersection of recommender systems, rewarded advertising, fraud prevention, and large-scale data processing. You'll work with frontier AI tools and workflows, including Claude, Codex, and LiteLLM.

What you'll be doing

• Architect & Design: Set the technical direction for Offer Delivery, owning the architecture of its services and leading design on its most critical initiatives.
• Build & Ship: Build, test, and ship the Golang and Java services that decide which offer each player sees, across real-time bidding into display auctions (OpenRTB) and direct placement outside the auction flow.
• Evolve the Recommender: Work with the ML modeling team to take ranking improvements from idea to production, covering feature retrieval, scoring data, model serving integration, and online experiments.
• Lead Across Teams: Offer Delivery sits between the auction, ML, platform, and product teams. Align them on shared decisions and drive delivery across team boundaries.
• Operate at Scale: Ensure the high availability and reliability of our production services, including on-call rotations and proactive system monitoring.
• Raise the Bar: Mentor engineers, set engineering standards, and lead by example on code and design quality.

What we're looking for

• Technical Leadership: Track record of owning a significant backend system, setting direction, making the architectural calls, and getting it delivered through others as well as yourself.
• High-scale distributed systems: Demonstrated ability to design and ship large-scale, highly available, latency-sensitive distributed services with complex business logic.
• Core Technologies: Strong proficiency in backend development using Go or Java (or clear ability to become effective in Go quickly). Working knowledge of gRPC with a willingness to adapt to the best tool for the job.
• Observability & Data Streaming: Practical experience with observability platforms (logging, metrics, monitoring/tracing) and message bus technologies for managing complex data streams.
• Integration Design: Track record of building new systems amid rapidly shifting requirements. You can design systems that are stable through three requirement changes, and you know which change should revise the core data flow.
• Cross-team influence & mentorship: Experience driving technical work across team boundaries and developing the engineers around you.

You might also have

• Experience building recommender systems, marketplace matching, or ads ranking systems in production.
• Experience building or operating a DSP, ad exchange, or real-time bidding system, with familiarity with OpenRTB, auction mechanics, or programmatic advertising.
• Working understanding of supply-side ad mediation, such as waterfall vs. bidding and adapter and SDK integration.

Additional information

Zone A: $200,400 - $260,500

Zone B: $178,300 - $231,800

Zone C: $157,800 - $205,200

This range reflects the anticipated base salary for this position. Beyond base salary, this role may be eligible for equity awards and participation in our company incentive plans (such as annual discretionary bonuses or sales commissions). The final offer amount will depend on several factors, including geographic location and the candidate’s relevant experience, professional background, and skill set.

Benefits

At Unity, we want our team members to thrive. We offer a wide range of benefits designed to support well-being and work-life balance.

Please note: Benefits eligibility, specific offerings, and coverage vary based on the country and employment status.

While specific benefits vary, here are some of the ways we strive to take care of our eligible team members globally: Comprehensive health, life, and disability insurance | Commute subsidy | Employee stock ownership | Competitive retirement/pension plans | Generous vacation and personal days | Support for new parents through leave and family-care programs | Office food snacks | Mental Health and Wellbeing programs and support | Employee Resource Groups | Global Employee Assistance Program | Training and development programs | Volunteering and donation matching program

Life at Unity

Unity [NYSE: U] is the world’s leading game engine, powering play for more than 3 billion consumers each month. The top mobile games in the world, the most played PC indie titles, the most innovative console games, and virtually all of the top XR and Web Games are developed, deployed, and grown in Unity. Unity also enables teams across industries like automotive, manufacturing, and healthcare to design, simulate, and collaborate in 3D — closing the gap between ideas and reality.

Unity is a proud equal opportunity employer. We are committed to fostering an inclusive, innovative environment and celebrate our employees across age, race, color, ancestry, national origin, religion, disability, sex, gender identity or expression, sexual orientation, or any other protected status in accordance with applicable law.