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 pipelines from Postgres to ClickHouse for analytics

• Dropping p99 latency in the hot write paths and looking into SQL query plans to make sure that we can move fast

• Tune CTR by analyzing impression and click data

• Improve core ad matching

• Improve observability with logs and custom metrics

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

We care about moving fast in the right direction. That means finding the highest-leverage problems and solving them. We experiment, measure, and improve. We build trust by being accountable and by building reliable systems that serve others.