AI engineer for subscription products

Ruby Labs Ltd; United States; Remote; USD 150,000 - 240,000; Full time

Benefits offered by this job

Remote work

Unlimited PTO

Paid holidays

MacBook provided

Contractor agreement

Tax advantages

Job summary

Ruby Labs Ltd is seeking a Senior AI Engineer to own and scale the AI layer of one of our core D2C subscription products. You will design, implement, and optimize AI workflows spanning prompts, LLM tooling, and production deployment.

You will build robust automation, manage costs and latency, and collaborate with product teams to translate metrics into business impact. This role supports globally distributed teams with remote work.

Qualifications

• 5+ years of software engineering with Node.js, TypeScript, Next.js, and Postgres.
• Production browser automation experience with Playwright at scale.
• Experience with dynamic prompting and JSON mode in production.

Responsibilities

• Design dynamic prompt templates with conditional logic and context injection that maximise generation quality
• Enforce predictable outputs with JSON mode, function calling, Zod/JSON schemas, validators, and repair loops
• 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
• Classify screens with a model inside each traversal, and decide what the model handles versus deterministic code
• Ship automations as frozen, published workers — versioned, reproducible, and safe to roll back
• Orchestrate runs through Hatchet with retries, timeouts, and failure traces that explain every broken run
• Build evaluation pipelines — test datasets, LLM-as-a-judge, RAGAS-style metrics — and score responses and screen classifications in Langfuse
• Trace complex LLM chains to find bottlenecks in cost, latency, and context-window usage
• Run A/B experiments across models and prompts through an AI gateway (OpenRouter, Cloudflare AI Gateway); release only on quantitative benchmarks
• Re-evaluate models as new architectures emerge; fine-tune when domain requirements demand it
• Take AI features from experiment to live production on Cloudflare Workers and Containers, and stay accountable after release
• Manage rate limits, fallbacks, and model cost so features stay reliable at scale
• Resolve production incidents in owned AI and automation systems with documented root-cause analysis

Skills

Node.js

TypeScript

Next.js

Postgres

Tools

Playwright

Browserbase

LangChain

LlamaIndex

Cloudflare Workers

Job description

Описание:

Ruby Labs is a leading tech company that creates and operates innovative consumer products. We offer a diverse range of opportunities across the health, education, and entertainment industries. Our innovative teams are driving the future of consumer-led products, and we're always looking for passionate individuals to join us. We are looking for a Senior AI Engineer to own and scale the AI layer of one of our core D2C subscription products.

Задачи:

• Design dynamic prompt templates with conditional logic and context injection that maximise generation quality
• Enforce predictable outputs with JSON mode, function calling, Zod/JSON schemas, validators, and repair loops
• 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
• Classify screens with a model inside each traversal, and decide what the model handles versus deterministic code
• Ship automations as frozen, published workers — versioned, reproducible, and safe to roll back
• Orchestrate runs through Hatchet with retries, timeouts, and failure traces that explain every broken run
• Build evaluation pipelines — test datasets, LLM-as-a-judge, RAGAS-style metrics — and score responses and screen classifications in Langfuse
• Trace complex LLM chains to find bottlenecks in cost, latency, and context-window usage
• Run A/B experiments across models and prompts through an AI gateway (OpenRouter, Cloudflare AI Gateway); release only on quantitative benchmarks
• Re-evaluate models as new architectures emerge; fine-tune when domain requirements demand it
• Take AI features from experiment to live production on Cloudflare Workers and Containers, and stay accountable after release
• Manage rate limits, fallbacks, and model cost so features stay reliable at scale
• Resolve production incidents in owned AI and automation systems with documented root-cause analysis

Требования:

• 5+ years of software engineering with Node.js, TypeScript, Next.js, and Postgres, including edge or serverless runtimes such as Cloudflare Workers
• Production browser automation with Playwright (Browserbase or similar): resilient selectors, retries, failure handling at scale
• Production experience with dynamic prompting — content that depends on input variables and injected context
• Structured outputs in production: JSON mode, function calling, Zod/JSON schemas
• Experience with unified LLM APIs or AI gateways (OpenRouter, Cloudflare AI Gateway): rate limits, fallbacks, cost-effective model selection
• LLM observability with Langfuse or similar: tracing, test datasets, scoring integration
• Evaluation methodology: RAGAS or custom LLM-as-a-judge systems
• Decides on benchmarks and trace data, not intuition
• Analytical — converts generation logs into metrics a business can act on
• Iterative — builds feedback loops and improves continuously
• Owns the outcome from experiment to production, and after
• Verifies before trusting — treats LLM output as unproven until validated
• Applicants from any country are welcome to apply for the position as long as they are located within approximately ± 4 hours of CET.

Условия:

• Remote Work Environment: Embrace the freedom to work from anywhere, anytime, promoting a healthy work-life balance.
• Unlimited PTO: Enjoy unlimited paid time off to recharge and prioritize your well-being, without counting days.
• Paid National Holidays: Celebrate and relax on national holidays with paid time off to unwind and recharge.
• Company-provided MacBook: Experience seamless productivity with top-notch Apple MacBooks provided to all employees who need them.
• Flexible Independent Contractor Agreement: Unlock the benefits of flexibility, autonomy, and entrepreneurial opportunities.
• Benefit from tax advantages, networking opportunities, reduced employment obligations, and the freedom to work from anywhere.