Founding AI Product Engineer — Agent & Experience

Pally (YC S25); San Francisco (CA); On-site; USD 200,000 - 300,000; Full time

Benefits offered by this job

Significant equity

401(k)

Health insurance

Job summary

Pally is a Bay Area startup building a personal assistant that lives in text messages. We’re hiring a senior to staff level engineer to own the agent and the experience, shipping product decisions from model outputs to the readouts on a phone.

This is a hands-on engineering role with product ownership: you’ll work in the agent code, prompts, evals, integrations, and the surfaces users interact with. You’ll be senior to staff level, with 4+ years shipping AI products, and a track record of

Qualifications

• 4+ years of software engineering, with experience at an AI product company, AI lab, or consumer product company.
• Hands-on experience building production agents with tool use, memory, and long-running conversations, and designing evals a team trusts to make ship decisions. Post-training or fine-tuning experience is a plus.
• A record of shipping features end to end and owning the outcome, not only the ticket: you can point to a metric that moved because of something you built.
• Full stack: TypeScript, React, and Next.js for the product, Python for evals, and Postgres on the back end.
• Strong product and design judgment. You notice when a word is wrong, a reply is too slow, or a flow has one step too many, and you fix it.
• Fluency with AI-assisted development workflows, grounded in the fundamentals to verify, correct, and own everything you ship.
• You want founding-team scope. You'll set the bar for how Pally works and help hire the engineers who join after you.

Responsibilities

• Own the agent and the experience: the tool-calling loop, memory and context assembly, prompts, and model routing so small, fast models take most turns and frontier models take the ones that matter.
• Build the harness that turns
• did that reply feel right?
• into a number: turn-level judges, replay of real conversations, regression suites that run before every deploy.
• Own the experience from onboarding to group chats and group teams, including the web app, and the moment a user texts us that they love it.
• Own features end to end, run experiments behind feature flags, keep what works, and delete what doesn't.
• Talk to users: read transcripts every day, talk to users every week, and study the numbers to inform what you build next.

Skills

4+ years software engineering

Agent development

Evaluation design

End-to-end feature shipping

Founding-team scope

AI-assisted development fluency

Strong product judgment

Tools

TypeScript

React

Next.js

Python

Postgres

Job description

Pally is a Bay Area startup building a personal assistant that lives in text messages. We’re hiring a senior to staff level engineer to own the agent and the experience, shipping product decisions from model outputs to the readouts on a phone.

This is a hands-on engineering role with product ownership: you’ll work in the agent code, prompts, evals, integrations, and the surfaces users interact with. You’ll be senior to staff level, with 4+ years shipping AI products, and a track record of