Principal/Senior Software Engineer - Mobile App Monetization (Ad Server)

PubMatic•Redwood City, CA

7d•Hybrid

About The Position

PubMatic is seeking an experienced Principal Software Engineer to lead the design and development of next-generation mobile app monetization capabilities. The role focuses on building high-performance, low-latency, scalable, and privacy-safe systems that increase publisher revenue from in-app inventory and improve DSP and buyer spend efficiency. It calls for expertise in mobile app advertising, SSP-DSP real-time bidding workflows, OpenRTB mobile signals, SDK and mediation integrations, traffic shaping, QPS optimization, mobile attribution, privacy constraints, and performance advertising. The engineer will develop systems that monetize formats including rewarded video, interstitial, native, banner, app-open, playable, and in-app video ads. They will collaborate with Product, Data Science, Marketplace Quality, DSP Partnerships, Publisher teams, MApp SDK, OpenBid/S2S integrations, and SRE to build data-driven and ML-integrated capabilities that improve yield, bid and win rates, fill rate, attribution readiness, latency, and reliability across PubMatic’s mobile app ecosystem. PubMatic is a scaled digital advertising platform serving publishers, media buyers, commerce companies, and data owners. The company describes a hybrid work schedule of three days in the office and two days working remotely.

Requirements

Five or more years of backend engineering experience and a proven record of building high-scale, low-latency systems; mobile app advertising, SSP, DSP, ad exchange, mediation, mobile SDK, app-install, or programmatic AdTech experience is preferred.
Strong knowledge of mobile app inventory signals, including app bundle, app store URL, SDK version, placement type, rewarded indicator, device identifiers, OS version, carrier, connection type, geography, consent status, and ad format metadata.
Familiarity with rewarded video, interstitial, native, banner, app-open, playable, and in-app video formats, including their effects on pricing, buyer demand, creative rendering, tracking, and user experience.
Strong understanding of mobile performance advertising, including app-install campaigns, CPI, CPA, ROAS, retention, lifetime value, post-install events, permitted retargeting, and buyer outcome optimization.
Experience or strong familiarity with mobile attribution and measurement ecosystems, including MMPs, AppsFlyer, Adjust, Singular, Firebase, SKAdNetwork, Android attribution changes, click and impression tracking, and delayed or aggregated conversion signals.
Strong knowledge of mobile privacy and compliance constraints, including Apple ATT, IDFA availability, Android Advertising ID, SKAdNetwork, Google Privacy Sandbox for Android, COPPA, GDPR, CCPA/CPRA, TCF, GPP, and do-not-sell/share flags.
Practical knowledge of mobile supply quality and fraud prevention, including app bundle, SDK, and device spoofing; geographic mismatch; VPN/proxy traffic; click injection and spam; invalid traffic; app-ads.txt; sellers.json; and SupplyChain object validation.
Excellent interpersonal, written, and verbal communication skills, with a collaborative mindset, strong ownership, and ability to work cross-functionally.
Bachelor’s degree in engineering (CS/IT) or an equivalent degree from a well-known institute or university.

Nice To Haves

Hands-on experience with mobile monetization SDKs, client-server ad request flows, mediation logic, in-app bidding, server-side bidding, waterfalls, or unified auction systems.
Contributions to open-source AdTech projects such as Prebid Mobile, RTBkit, OpenRTB tools, header bidding libraries, or mobile SDK/ad-serving frameworks.
Familiarity with ML model-serving infrastructure for real-time inference in high-QPS, low-latency environments.
Understanding of mobile user acquisition, performance DSPs, app-install campaigns, MMP integrations, and attribution platforms.
Experience with incrementality measurement, retargeting systems, audience segmentation, cohort-based optimization, or privacy-safe targeting for mobile performance marketing.
Exposure to privacy-preserving user ID solutions such as UID2.0, RampID, publisher first-party IDs, and permitted hashed identifiers, as well as SKAdNetwork for iOS post-ATT monetization.
Experience with cross-format mobile monetization strategies within the same app session.
Familiarity with real-time analytics pipelines measuring bid rate, win rate, fill rate, eCPM, revenue, QPS efficiency, timeout rate, attribution feedback, buyer spend, and yield efficiency.
Publications, patents, internal platform leadership, or speaking engagements in mobile monetization, AdTech infrastructure, RTB optimization, privacy-safe advertising, or ML for AdTech.
Active use of generative AI tools and IDEs, such as GitHub Copilot, ChatGPT, Claude, Cursor, or Windsurf, to accelerate development, improve code quality, automate repetitive work, and enhance documentation and debugging.

Responsibilities

Architect and implement scalable backend services for mobile app monetization, including privacy-safe processing of in-app behavioral data using on-device computation, data aggregation, and differential privacy.
Build and optimize SSP-DSP mobile inventory workflows, including app bundle validation, device and geographic signals, privacy-aware user signals, bid responses, loss analysis, and DSP troubleshooting.
Design mobile traffic-shaping and QPS optimization systems that prioritize inventory using bid and win probability, spend potential, app quality, device and geographic signals, ad format, consent availability, and DSP buying behavior.
Improve runtime handling of mobile ad formats, including eligibility, creative compatibility, response validation, tracking, completion, and reward-callback correctness.
Improve buyer and DSP compatibility by ensuring mobile app requests are well-represented, privacy-compliant, format-compatible, attribution-ready, and supply-quality-aware.
Develop mobile supply-quality systems and diagnostics, including app metadata and bundle validation, app-ads.txt and sellers.json checks, SupplyChain object validation, spoofing detection, invalid-traffic indicators, device/geographic consistency checks, and low-quality partner supply detection.
Support privacy-aware and attribution-ready advertising, including ATT/IDFA handling, AAID availability, consent enforcement, COPPA treatment, SKAdNetwork readiness, MMP signal passing, click and impression tracking, and privacy-safe fallbacks when user-level identifiers are unavailable.
Partner with MApp SDK and OpenBid/S2S teams to define signal-quality standards, request-field expectations, placement and ad-unit semantics, tracking requirements, and partner feedback loops.
Build publisher- and buyer-facing diagnostics for missing fields, app quality, buyer no-bids, fill and eCPM, tracking mismatches, attribution readiness, and supply-path quality.
Work with DSP Partnerships and Marketplace Quality to improve buyer confidence by addressing format compatibility, attribution readiness, privacy eligibility, fraud risk, supply transparency, and app inventory quality.
Collaborate with Product, Data Science, Publisher teams, DSP Partnerships, Marketplace Quality, MApp SDK, OpenBid/S2S integrations, and SRE to define and execute the mobile advertising roadmap.
Champion operational excellence through observability, reason codes, structured logs, dashboards, alerts, safe rollouts, latency protection, production debugging, and cross-team incident response.