Senior AI Engineer - Production LLM & Browser Automation

Ruby Labs Ltd; New York (NY); Remote; USD 150,000 - 230,000; Full time

Benefits offered by this job

Remote Work Environment

Unlimited PTO

Paid National Holidays

Company-provided MacBook

Flexible Independent Contractor Agree

Job summary

Ruby Labs Ltd in New York is seeking a Senior AI Engineer to own and scale the AI layer of our core D2C subscription product. You will oversee production LLM features, browser automation, prompts, schemas, evaluation, observability, and model selection from experimentation to live release.

This high-impact role requires data-driven decision making, strong TypeScript stack experience, and cost-aware architecture.

Qualifications

• 5+ years of software engineering with Node.js/TypeScript/Next.js and Postgres.
• Production browser automation with Playwright and Browserbase or similar.
• Experience with dynamic prompting and JSON structured outputs.
• Experience with unified LLM APIs or AI gateways and cost-aware model selection.
• LLM observability, tracing, and evaluation methodologies.

Responsibilities

• Design dynamic prompt templates with conditional logic and context.
• Enforce outputs with JSON mode, function calling, and validators.
• Own LLM workflows integrating into application logic.
• Build and maintain browser automation to traverse web flows.
• Classify screens and separate model handling from deterministic code.
• Ship and version automations as reproducible workers.
• Orchestrate runs with retries, timeouts, and fault tracing.
• Build evaluation pipelines and score responses and classifications.
• Run A/B experiments across models and prompts with quantitative benchmarks.
• Take AI features from experiment to production and own outcome.

Skills

Node.js

TypeScript

Next.js

PostgreSQL

Edge/Serverless

Browser automation

Prompt design

LLM evaluation

Observability

Data-driven decisions

Tools

Playwright

Browserbase

Langfuse

LangChain

LlamaIndex

OpenRouter

Job description

Ruby Labs Ltd in New York is seeking a Senior AI Engineer to own and scale the AI layer of our core D2C subscription product. You will oversee production LLM features, browser automation, prompts, schemas, evaluation, observability, and model selection from experimentation to live release.

This high-impact role requires data-driven decision making, strong TypeScript stack experience, and cost-aware architecture.