Software Engineer - Backend

Koah Labs Job OpportunityKoah Labs is building the ad network to power the next generation of AI-native products. Our mission is to help publishers monetize and help advertisers reach the right audience — without compromising speed, UX, or privacy.We're a small, tight-knit team in San Francisco with backgrounds at X, Apple, Meta and early-stage startups. We've raised from top investors and are growing fast with real traction on both the publisher and advertiser sides of the marketplace.Working at Koah means joining at the ground floor: you'll ship code that shapes the company and the ecosystem we're building. We move quickly, operate with high trust, and care deeply about craft.Our StackInfra: Terraform, AWS, LGTM (Loki, Grafana, Tempo, Mimir), Tailscale, CloudflareData: PostgreSQL, ClickHouse, Redis, Kafka, PythonCore Application: Ruby on Rails, React, TypeScriptSDKs: Flutter, React Native, Android, iOSExample projectsBuild scalable data models that support multiple impressions for an ad request allowing us to align publisher and advertiser interestsDesign abstractions that allow us to experiment and ship new formats that allow for a flexible way of tracking engagement eventsBuild a low-latency frequency capping system to improve an end user's experience and prevent ad fatigueCreate schemas to represent high-volume ad bidding with ad exchanges to increase the diversity of the ad demand on platformEvolve our real-time auction and ad-decisioning systems to improve publisher, advertiser, and user outcomesYou might be a fit ifYou like debugging and optimizing performanceYou are detail oriented and like to create good abstractions that others rely onYou enjoy experimentation, measuring, and creating reliable systemsYou want ownership of foundational systemsYou enjoy working closely with product and data science to turn ambiguous problems into measurable outcomes