Research Engineer, HCI and Agent Experience San Francisco / Mountain View, CA or remote ·

Pally; San Francisco (CA); Hybrid; USD 200,000 - 300,000; Full time

Benefits offered by this job

Equity

401(k)

Health insurance

In-person in SF

Job summary

Pally in San Francisco, CA is seeking a senior-to-staff software engineer to own the agent and the experience. This hands-on role spans the agent code, prompts, evals, integrations, and product surfaces, with weekly shipping and direct user interaction.

You’ll design how the agent decides to act, build tool-use loops, memory and context assembly, and the prompts that guide fast, reliable replies on mobile. This role emphasizes end-to-end ownership, metric-driven shipping, and close collaboration

Qualifications

• 4+ years of software engineering with AI product experience.
• Hands-on experience building production agents with tool use, memory, and long-running conversations.
• Track record of shipping features end to end with measurable impact.
• Full stack capabilities: TS/React/Next.js, Python, and Postgres.
• Strong product and design judgment.
• Fluency with AI-assisted development workflows.
• Founding-team scope: helping hire and set engineering bar.

Responsibilities

• Own agent behavior design including tool-calling loop and prompts.
• Build eval harness and regression suites.
• Shape the user experience across mobile and web.
• Own features end to end from idea to deployment.
• Engage with users, read transcripts, and study metrics.

Skills

AI product shipping

Agent development

Evaluation design

User-facing product ownership

Tools

TypeScript

React

Next.js

Python

Postgres

Tool use / memory models

Job description

San Francisco, CA Full-time, in person

The role

You’ll own the agent and the experience. Most of Pally is a text thread. There are no buttons, no spinners, no dashboard. Every product decision comes out of the model as a sentence, and every sentence has to be right, fast, and able to actually get something done. You’ll own all of it, from how the agent decides what to do, to the tools it uses, to how the reply reads on a phone.

This is a hands-on engineering role with a lot of product ownership. You’ll be in the agent code, the prompts, the evals, the integrations, and the product surfaces, talking to users and shipping to them every week. In practice that means:

• The agent. Design and build how Pally decides to act, ask, wait, or reach out first: 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.
• Evaluations. 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.
• The experience. How Pally reads on a phone, from the first reply to a follow-up weeks later. Onboarding, group chats, teams, approvals, and the web app. The first five minutes decide whether someone texts Pally again.
• Product features. Own features end to end, from idea to the moment a user texts us that they love it. Run experiments behind feature flags, keep what works, and delete what doesn’t.
• Talking to users. Read transcripts every day, talk to users every week, and study the numbers. What you learn decides what you build next.

We’ll measure you on one thing: how much better Pally gets at being someone’s assistant, week over week, in the evals and in how many people text it every week.

Profile

This is a senior to staff level role. We’re looking for someone who has shipped AI products people use every day, at a frontier AI lab, an AI product company, or a team operating at that level.

• 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.

Practical stuff

$200-300k base + significant equity, 401(k), and health insurance. Full-time, in person in San Francisco, CA.

We work exceptionally hard. If work isn’t your primary focus, this isn’t for you. However, we also give you full autonomy over your schedule. We don’t care when you work hard, only that you do.

Thanks for reading,