Software Engineer - Product

Who We Are Koah 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 Stack - Infra: Terraform, AWS, LGTM (Loki, Grafana, Tempo, Mimir), Tailscale, Cloudflare - Data: PostgreSQL, ClickHouse, Redis, Kafka, Python - Core Application: Ruby on Rails, React, TypeScript - SDKs: iOS, Android, Web, Flutter, React Native In this role, you will: - Help shape the foundation of our engineering organization - Lead initiatives across the stack, with high agency in product direction and technical design - Dive deeply into technically challenging and rewarding work, whether it is optimizing our matching algorithms or creating world class experiences that reach millions of users - Partner with cross functional stakeholders in data and GTM to drive product direction that our customers need - Embrace an experimentation mindset - we are constantly trying to learn about how users are interacting with AI-native products, and use data from these experiments to drive our work. You might thrive in this role if you: - Have experience building and scaling production quality systems and experiences - Are comfortable working across the stack, tackling new tasks out of your comfort zone, and can handle ambiguity - Work well in-person and enjoy fast feedback loops - Enjoy breaking down problems and testing your hypotheses - Get excited about end-to-end ownership within high agency environments - Have been a startup founder or an early-stage engineer