---
title: 'Senior Engineer, Backend/Infra at AgentMail'
canonical: 'https://feeny.ai/job/senior-engineer-backend-infra-agentmail-san-francisco-5z8yf46hk0fw'
type: 'job'
last_seen: '2026-09-09'
---

# Senior Engineer, Backend/Infra at AgentMail

- **Company:** AgentMail
- **Location:** San Francisco, CA
- **Compensation:** $250k–$400k
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2026-03-09
- **Last confirmed live:** 2026-09-09
- **Apply:** https://jobs.ashbyhq.com/agentmail/ebf7b980-892d-42ba-8777-c004755045ae

## Job description

Location: San Francisco, CA

Type: Full-time, on-site

TLDR: we are seeing a surge in market demand as agents become real first-class citizens of the internet, and we are aggressively hiring in order to keep up. We're coming up with solutions in a problem space where no one in Silicon Valley knows the answer to either: how to build something agents want. If you like owning things 0 -> 1, lets chat.

AgentMail is building an API designed to give inboxes to AI agents and be the sole identity + communication provider. It isn't AI for your email, it's email for your AI.

We’re looking for a founding engineer with strong backend and infra instincts to help build the primitives agents will use to communicate, authenticate, and operate in the real world. This is a role for someone who likes systems work: APIs, distributed infrastructure, reliability, developer tooling.

Company highlights:

- World-Class Team: Founded by a team of experts in their own respects(Quant, SWE, Private Equity), the team has top-tier talent from startups and big companies alike, with backgrounds from Optiver, NVIDIA, Amazon, Modern Treasury, KKR.
- Hypergrowth: We’ve doubled our user count every 2 weeks since January, and don’t plan on slowing down any time soon. As agents will outnumber humans very soon, we see this multiple changing in the range of orders very soon.
- Competitive-edge: We are the sole identity provider for agents. Just like you have a Gmail, agent’s will need an AgentMail.

## WHAT YOU’LL DO

- Lead and manage a team of 4-6 engineers
- Design APIs and abstractions that are intuitive for both humans and AI Agents
- Build high-performant, low-latency systems with the idea that agents are the end-users in mind
- Get your hands dirty by touching our core infrastructure that processes hundreds of thousands of emails per day.
- Think creatively about being the bridge between cutting edge AI capabilities with something as primitive as email(an oxymoron we know)
- Own projects end-to-end, from system design to production rollout
- Write clear, maintainable code and strong technical documentation
- Be the frontline for feedback from our customers - we’ll trust you to be our spokesperson

## WHAT WE’RE LOOKING FOR

- You want to solve problems end-to-end: every engineer owns a part of the product and needs to make decisions across the frontend, infrastructure, backend, and UX.
- You have a high bar for quality: At a startup, speed is the only advantage we have over big-tech companies. But even more important is to care about your output and obsess about details.
- You are a clear thinker and communicator: We have daily standups and weekly syncs in which we expect you to communicate tradeoffs, problems, and blockers directly.
- You are highly technical: preferred you have prior experience shipping production software by real users as a software engineer at a tech company or startup. But hustlers are always appreciated.

## BONUS POINTS

- Experience with cloud infrastructure, distributed systems, or developer tools
- Experience with messaging, email, auth, or protocol-heavy systems
- Experience building for AI/LLM use cases

Qualifications:

- Has 3+ years of work experience as an engineer working on infrastructure at a tech company
- Has architected software used in production by millions of users

## COMPENSATION:

- $250k - $400k base salary
- 1.0% - 2.0% equity
- Breakfast, lunch, and dinner (Doordash)
- Medical, dental, and vision insurance
- Equinox membership

## About AgentMail

## Company Overview
- **One-liner**: AgentMail provides an API-first email inbox service built specifically for AI agents, enabling them to send, receive, and manage emails autonomously.
- **Entity Type**: Private (YC S25, Seed-stage)
- **Headquarters**: San Francisco, California, United States
- **Founded**: 2025
- **Founders**: Haakam Aujla, Adi Singh, Michael Kim

## Core Business
- **Primary industry**: Email infrastructure / AI agent tooling
- **Target customers**: B2B – developers and platform builders creating AI agents that need to communicate via email
- **Mission or purpose**: To give every AI agent its own email inbox, enabling identity, communication, and persistent memory on the internet.

## Products & Services
- **AgentMail API**: REST API to programmatically create inboxes, send/receive emails with full threading, attachments, and multi-party support. Includes webhooks, WebSockets, custom domains (DKIM/SPF/DMARC), and semantic search. [agentmail.to](https://www.agentmail.to/)
- **SDKs & MCP Server**: Python and TypeScript SDKs, plus an MCP (Model Context Protocol) server for AI tool integration. [agentmail.to](https://www.agentmail.to/)
- **IMAP & SMTP Access**: Legacy protocol support alongside the API for compatibility. [agentmail.to](https://www.agentmail.to/)
- **Multi-tenant Pods**: For platform builders who need to manage inboxes across many customers. [agentmail.to](https://www.agentmail.to/)

## Market Standing
- **Valuation/Market Cap**: Not publicly available (private company)
- **Key Metric**: Total Funding – $6.625M (as of March 2026) [linkedin.com](https://www.linkedin.com/company/agentmailto)
- **Notable Investors/Partners**: Y Combinator (S25), General Catalyst (lead in later seed round), Paul Graham, Paul Copplestone (Supabase founder), Karim Atiyeh (Ramp founder). [ycombinator.com](https://www.ycombinator.com/companies/agentmail)
- **Growth Signals**: Team size ~10 (up from 8, +200% YoY); 5,800+ LinkedIn followers (+5.4% monthly); 3 active job postings; backed by top-tier investors. [linkedin.com](https://www.linkedin.com/company/agentmailto)

## Competitive Advantages
- **First-to-market for AI-native email**: Built from scratch for agent use cases, unlike legacy providers (Gmail, Outlook) that lack API-first inbox creation and impose restrictive rate limits.
- **Fully managed persistent inboxes**: Handles parsing, threading, labeling, searching, and replying – agents get the same email experience as humans without building custom logic.
- **Developer-first design**: Simple API key auth, no OAuth headaches, built-in permissions and guardrails, semantic search across all inboxes.
- **Scalable infrastructure**: Usage-based pricing without per-inbox monthly fees, designed to handle high volumes of emails and inboxes.

## Strategic Focus
- **Current priorities**: Scaling the platform to meet growing demand from AI agent builders; expanding SDK support and integrations; hiring engineering, GTM, and operations talent to accelerate product development and market adoption. [ycombinator.com](https://www.ycombinator.com/companies/agentmail/jobs)
- **Direction**: Become the default email infrastructure layer for the AI agent ecosystem, enabling agents to communicate, authenticate, and transact via email just like humans.

## Why Work Here
- **Culture**: Small, YC-backed team (10 people) working on hard infrastructure problems at the intersection of email protocols and AI. Founders have backgrounds at Optiver, NVIDIA, and Accel. [ycombinator.com](https://www.ycombinator.com/companies/agentmail)
- **Remote/Hybrid**: Based in San Francisco; likely in-office given the early-stage startup nature, but not explicitly stated.
- **Perks & Engineering Culture**: Competitive salary ($110K–$400K depending on role) plus meaningful equity (0.20%–2.00%). Opportunity to shape the product from the ground up, work with cutting-edge AI tooling, and join a fast-growing company backed by top investors. [ycombinator.com](https://www.ycombinator.com/companies/agentmail/jobs)

## Sources
1. [agentmail.to](https://www.agentmail.to/) – Company website, product description, and career page
2. [ycombinator.com](https://www.ycombinator.com/companies/agentmail) – Y Combinator company profile (funding, founders, team size, open roles)
3. [linkedin.com](https://www.linkedin.com/company/agentmailto) – LinkedIn company page (funding rounds, headcount growth, investors, executive team)

## Other roles at AgentMail

- [Agent Experience Engineer](https://feeny.ai/job/agent-experience-engineer-agentmail-san-francisco-x2gzg5c28249) — San Francisco, CA
- [Founding PLG & Community Lead](https://feeny.ai/job/founding-plg-community-lead-agentmail-san-francisco-hxwsf3nnqjq6) — San Francisco, CA
- [Founding GTM & Operations Lead](https://feeny.ai/job/founding-gtm-operations-lead-agentmail-san-francisco-yw31f1tp18z0) — San Francisco, CA
- [GTM Engineer](https://feeny.ai/job/gtm-engineer-agentmail-san-francisco-eehm2x1gjdc3) — San Francisco, CA
- [Founding Engineer](https://feeny.ai/job/founding-engineer-agentmail-san-francisco-e4apbq47g5qj) — San Francisco, CA