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, and early-stage startups. We’ve raised $5.7M from top investors and are growing fast with real traction on both the publisher and advertiser sides.

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.

Tooling

• Infra: Render (app + workers), AWS (RDS, S3), Grafana for metrics and logs

• Data: PostgreSQL (primary), ClickHouse (analytics), Redis (caching & rate limiting)

• Core Stack: Ruby on Rails, React, TypeScript

• SDKs: Flutter, React Native, Android (Kotlin, Compose), iOS (Swift)

We’re looking for engineers who like digging into systems and making them fast, reliable, and easy to operate. You’ll help us deliver ads quickly, track performance accurately, and scale the platform as we grow. We’re building systems that will soon operate at the scale of modern analytics platforms — high-volume, low-latency, and deeply queryable.

Example projects

• Build ETL pipelines from Postgres to our OLAP database for analytics

• Drop p99 latency in the hot write paths by improving SQL query plans, improving retry logic, and setting strict third party timeouts

• Tune converstion and clickthrough rate metrics in our core ad matcher from analyzing impression and click data

• Improve observability with logs and custom metrics that make it easy for us to understand why certain ad was chosen

You might be a fit if

• You like debugging and optimizing performance

• You are detail oriented and use data to support your claims

• You enjoy digging deeply and owning the platform side supporting product

• You enjoy experimentation, measuring, and creating reliable systems

If you're interested, please send an email to careers@koahlabs.com with your full name, email address, and resume.