Senior AI Engineer

Ruby Labs is hiring a Senior AI Engineer to own the AI layer of a consumer subscription product, taking LLM features from experimentation through production and ongoing operation. Responsibilities include dynamic prompts, structured outputs, model selection, evaluation pipelines, observability, and managing reliability, latency, and cost. Browser automation with Browserbase and Playwright accounts for roughly half the role.

The position requires 5+ years of software engineering experience and production experience with TypeScript, Node.js, Next.js, Postgres, browser automation, and LLM systems. The stack includes Cloudflare Workers and Containers, Hatchet, and Langfuse. Applicants must be located within approximately four hours of CET. The listing describes a full-time role under an independent contractor agreement, with unlimited PTO, paid national holidays, and a company-provided MacBook.

Highlights

• Own production AI features and incident resolution end to end.
• Evaluate models and prompts using quantitative benchmarks.
• Build reliable, versioned browser automation.
• Remote eligibility includes the European Union.