Founding Engineer

Location: San Francisco, CA
Company Stage of Funding: Seed AI Infrastructure Startup ($6M Raised)
Office Type: Onsite (5 Days Per Week)
Salary: $150,000–$250,000 + 0.5%–1% Equity

Company Description

We're representing a fast-growing AI infrastructure startup building the identity and communication layer for AI agents. Just as email transformed communication for people, this platform enables AI agents to securely communicate, authenticate, and operate across real-world applications.

Backed by leading investors and operators including Paul Graham, executives from Ramp, HubSpot, and Supabase, the company has experienced rapid growth with its user base doubling every two weeks. As one of the earliest engineers, you'll build foundational infrastructure powering AI agent communication while working directly alongside the founders in a highly collaborative, product-focused environment.

What You Will Do

• Design and build backend APIs and infrastructure that enable AI agents to communicate, authenticate, and perform real-world tasks.
• Own product initiatives from initial concept through architecture, implementation, deployment, and ongoing iteration.
• Build scalable backend systems supporting production workloads, distributed services, and developer-facing APIs.
• Develop integrations with email protocols such as IMAP and SMTP, along with authentication and messaging infrastructure.
• Contribute across the full stack as needed, with a primary focus on backend engineering.
• Partner directly with customers to understand requirements and support enterprise deployments.
• Propose and execute new product ideas, growth experiments, and platform improvements.
• Write maintainable, well-documented code that supports high-volume production systems.
• Collaborate closely with the founding team to shape product direction, engineering culture, and long-term architecture.
• Help build the technical foundation for a category-defining AI infrastructure platform.

Ideal Background

• 0–5 years of professional software engineering experience, with flexibility for exceptional candidates.
• Experience building production software at a leading technology company or well-known venture-backed startup.
• Proven ability to own projects from concept through production deployment.
• Strong backend engineering fundamentals, including REST API design, distributed systems, and server-side architecture.
• Experience with TypeScript or other modern programming languages.
• Familiarity with cloud infrastructure, scalable backend services, and production databases.
• Strong computer science fundamentals and system design skills.
• Excellent communication skills with the ability to explain technical tradeoffs clearly.
• High ownership mindset with the initiative to identify opportunities beyond assigned work.
• Must be authorized to work in the United States without current or future employer sponsorship.

Preferred

• Experience building email, messaging, or protocol-heavy systems using technologies such as SMTP or IMAP.
• Background at companies such as FAANG, high-growth Series A+ startups, or leading quantitative trading firms.
• Experience with AI infrastructure, LLM tooling, developer platforms, or agent-based systems.
• Startup experience building zero-to-one products with significant ownership.
• Experience with cloud infrastructure, distributed systems, and developer tooling.
• Evidence of initiative through entrepreneurship, competitive athletics, research, fellowships, or substantial personal projects.
• Passion for AI infrastructure and emerging agent ecosystems.
• Comfortable working in a fast-paced, highly collaborative onsite startup environment.

Compensation and Benefits

• Base salary: $150,000–$250,000.
• Equity: 0.5%–1%, with flexibility for exceptional candidates.
• Complimentary Equinox membership.
• Daily DoorDash breakfast, lunch, and dinner.
• Opportunity to join one of the earliest engineering teams building foundational infrastructure for AI agents.
• Direct collaboration with experienced founders and significant ownership over product and technical direction.
• Please note that visa sponsorship is not available for this position; candidates must already have permanent U.S. work authorization.