Full Stack Developer

Hazel; New York (NY); Hybrid; USD 150,000 - 250,000; Full time

Benefits offered by this job

Base salary $150-250K base

Equity 0.15-0.5%

Top-tier health, dental, vision

Hybrid in NYC

Job summary

Hazel in New York City seeks an engineer to extend Hazel's action layer, enabling writes into Shopify and other connected systems. You’ll build product bundles, launch A/B tests in Klaviyo, and refine the human-in-the-loop scaffolding.

You’ll own full-stack features (TypeScript/React + Go services) and design AI agent workflows with streaming LLMs and multi-step tool use, integrating with Shopify, Klaviyo, Meta, Amazon, and more.

Qualifications

• Production LLM feature experience.
• Owned an API at scale: query optimization & schema design.
• Strong TypeScript experience.
• Experience with AI agent workflows and tool use.

Responsibilities

• Extend Hazel's action layer to write into connected systems (Shopify, etc.).
• Deliver full-stack features using TypeScript/React and Go services.
• Design and implement AI agent workflows with streaming LLM responses and multi-step tool use.

Skills

Strong TypeScript

Go services

API design

AI workflows

LLM features

Tools

Shopify

Klaviyo

Meta APIs

Amazon APIs

Job description

About Hazel

Hazel is the AI coworker for consumer brands. We connect to a brand's live data - Shopify, Klaviyo, Amazon, Meta, and dozens of others - and turn it into a teammate operators talk to every day. Ask "why did repeat purchase rate drop last week?" and 10 seconds later you get an answer, cited from live data.

Hazel also takes action herself, proactively flagging issues and making changes directly in Shopify and the other systems she connects to, on the way to running full playbooks autonomously.

We've raised more than $2M, are rapidly scaling, and serve some of the biggest consumer brands including Bogg Bag, Ultra, and OneSkin. You'll join a small, senior engineering team working directly with the founders.

What you'll work on

In your first 60 days, you'll be extending Hazel's action layer - the writes back into the systems she connects to. Think: creating product bundles in Shopify, launching A/B tests in Klaviyo, and the human-in-the-loop scaffolding that makes all of it safe.

Beyond that:

• Full-stack product features across TypeScript/React + Go services

• AI agent workflows: streaming LLM responses, multi-step tool use, approvals

• Integrations across Shopify, Klaviyo, Meta, Amazon, and more, both reading and writing

you'll work directly with the founders and customers. Code you ship today is in front of operators tomorrow.

Who we're looking for

• You've shipped a production LLM feature to real users.

• You've owned an API at scale: query optimization, schema design, picking the right tool for the workload.

• Strong TypeScript experience

• You use coding agents to do the work of a much larger team, and you can tell us where they helped and where they made things worse.

• You care deeply about how the product ergonomics and UX.

• Former or aspiring founders

This isn’t for you if…

• You want product specs handed to you. Your manager is the customer.

• You're low agency

• You aren't excited about

Comp & benefits

• $150-250K base

• 0.15-0.5% equity

• Top-tier health, dental, vision

• Hybrid in NYC (ask about our pool table)

How we hire

1. 15-min intro

2. Founder call

3. Technical interview

4. Onsite - meet the team

5. Offer