Software Engineer - Infrastructure

Koah; San Francisco (CA); On-site; USD 180,000 - 240,000; Full time

Job summary

Koah Labs is hiring engineers to design, build, and maintain the infrastructure that powers our adtech platform in San Francisco. You’ll own the breadth of systems across infra, data, and core applications, with focus on reliability, performance, and scale.

You’ll work closely with product and the data teams, operating in a fast-moving startup environment where craft and speed matter. Join us on the ground floor and help shape our growing stack.

Qualifications

• Experience maintaining production systems at scale.
• Strong focus on performance and reliability.
• Ability to own the platform layer end-to-end.
• Enjoy experimentation and measurement to build reliable systems.

Responsibilities

• Design, build, and maintain Koah's infrastructure powering the adtech platform.
• Own the breadth of systems across infra, data, and core applications.
• Identify bottlenecks, implement scalable improvements, and monitor health of production systems.

Skills

Production-scale systems

Performance-oriented

Platform ownership

Problem solving

Tools

Ruby on Rails

React

TypeScript

PostgreSQL

Kafka

Job description

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: Flutter, React Native, Android, iOS

The Role

We are looking for strong engineers with experience and interest in designing, building, and maintaining the infrastructure that make up our adtech platform.

You might be a fit if

• You have maintained or operated serious systems in production at scale




• You are detail-oriented and care about performance




• You enjoy diving deep into problems and owning the platform layer that powers our product




• You enjoy experimentation, measuring, and creating reliable systems




• You want to own a breadth of systems