Senior AI Engineer

Ruby Labs; Georgia; Remote; USD 140,000 - 190,000; Full time

Benefits offered by this job

Paid national holidays

Flexible independent contractor quiet?

Work from anywhere

Job summary

Ruby Labs Ltd is seeking a Senior AI Engineer to own and scale the AI layer of a core D2C subscription product. You’ll own production LLM features and the browser automation built around them end to end — prompts, outputs, evaluation, and observability.

Work in a modern TypeScript stack (Next.js, Cloudflare Workers, Playwright) and drive model selection, cost efficiency, and reliability. This is a high-impact role with data‑driven decisions and shipped automation as frozen, versioned workers.

Qualifications

• 5+ years of software engineering with Node.js, TypeScript, Next.js, and Postgres.
• Production experience with dynamic prompting and structured outputs in production.
• Experience with unified LLM APIs or AI gateways (OpenRouter, Cloudflare AI Gateway).
• Ability to decide on benchmarks and trace data, not intuition.

Responsibilities

• Design dynamic prompt templates with conditional logic and context injection.
• Own complex LLM workflows that integrate into application logic.
• Build and maintain browser automation on Browserbase Functions and Playwright.
• Ship automations as frozen, published workers — versioned and safe to roll back.
• Build evaluation pipelines and score responses and classifications in Langfuse.
• Run A/B experiments across models and prompts through an AI gateway.
• Resolve production incidents in owned AI and automation systems.

Skills

Node.js

TypeScript

Next.js

Postgres

Cloudflare Workers

Browser automation

Playwright

LangChain

LlamaIndex

Langfuse

OpenRouter

AI Gateways

Tools

LangChain

LlamaIndex

Browserbase Functions

Playwright

Hono

Hatchet

Drizzle

Supabase

Vercel

Next.js

Job description

Ruby Labs is a leading tech company that creates and operates innovative consumer products. We are looking for a Senior AI Engineer to own and scale the AI layer of one of our core D2C subscription products. You will be fully responsible for production LLM features and the browser automation built around them end to end — prompt systems, structured outputs, evaluation, observability, and model selection — from first experiment to live release, with quality, reliability, and cost as your accountability.

This is a high-impact role suited for someone who decides with data, not intuition. You work in a modern TypeScript stack — Next.js, Cloudflare Workers and Containers with Hono, Hatchet task queues, Drizzle on Supabase Postgres, Vercel Blob.

Prompt Systems & Structured Outputs

• Design dynamic prompt templates with conditional logic and context injection that maximise generation quality
• Own complex LLM workflows (LangChain, LlamaIndex, or custom) that integrate cleanly into application logic
• Build and maintain browser automation on Browserbase Functions and Playwright that traverses web flows reliably
• Ship automations as frozen, published workers — versioned, reproducible, and safe to roll back
• Build evaluation pipelines — test datasets, LLM-as-a-judge, RAGAS-style metrics — and score responses and screen classifications in Langfuse
• Run A/B experiments across models and prompts through an AI gateway (OpenRouter, Cloudflare AI Gateway); Take AI features from experiment to live production on Cloudflare Workers and Containers, and stay accountable after release
• Resolve production incidents in owned AI and automation systems with documented root-cause analysis

• 5+ years of software engineering with Node.js, TypeScript, Next.js, and Postgres, including edge or serverless runtimes such as Cloudflare Workers
• Production experience with dynamic prompting — content that depends on input variables and injected context
• Structured outputs in production: Experience with unified LLM APIs or AI gateways (OpenRouter, Cloudflare AI Gateway): rate limits, fallbacks, cost-effective model selection
• Decides on benchmarks and trace data, not intuition

Ruby Labs operates within the CET (Central European Time) zone. Remote Work Environment:

Remote Work Environment

• Paid National Holidays: Celebrate and relax on national holidays with paid time off to unwind and recharge.
• Flexible Independent Contractor Agreement: Benefit from tax advantages, networking opportunities, reduced employment obligations, and the freedom to work from anywhere.

Life at Ruby Labs

At Ruby Labs, we move fast, aim high, and expect the same from our team. If you’re hungry to achieve, motivated by impact, and want to grow at the speed of your own ambition, Ruby Labs offers the platform to make it happen.

LI-Remote