As a Founding Engineer at this YC S25 startup, you will build the critical identity and communication layer for the agentic era. You will design high-throughput backend systems and APIs that serve as the inbox for AI agents, enabling them to communicate and authenticate as independent digital citizens in a rapidly expanding market.
Founding Engineer at Generalcatalyst
Join a YC S25 startup backed by General Catalyst and Paul Graham as a Founding Engineer building the identity and communication layer for AI agents. With $6M in seed funding and a team from NVIDIA and Amazon, this San Francisco-based company is creating the 'Gmail for agents' to help them communicate and operate as independent entities. If you're a high-bar systems engineer who wants to own core infrastructure processing 100M+ emails for a user base that doubles every two weeks, this is your chance to shape a new category of the internet.
About this role
Role overview
About the company
Generalcatalyst
$6M Seed AI infrastructure startup backed by General Catalyst and Paul Graham
What you'll do
What you will do
- Design and implement intuitive APIs and abstractions that allow AI agents to operate as first-class citizens of the internet.
- Build and scale distributed systems and core infrastructure capable of processing over 100 million emails per day with low latency.
- Own projects end-to-end, from initial system design to production rollout, while collaborating directly with the founding team and customers.
Who you are
Who this is a fit for
- Strong backend and systems engineering background with experience shipping production-grade software at a high-growth tech company or startup.
- Deep understanding of distributed systems, cloud infrastructure, or developer tools, with a preference for messaging and protocol-heavy experience.
- High-velocity builder who thrives in ambiguity and obsesses over quality, detail, and solving complex problems from 0 to 1.
Why this role
Why this role is remarkable
- Work at the frontier of AI infrastructure with $6M in funding from General Catalyst, Paul Graham, and the CTO of HubSpot.
- Join a high-performance team of 8 hailing from NVIDIA, Amazon, and Optiver, currently doubling their user count every two weeks.
- True founding impact with significant equity and the opportunity to define a new category of the internet where agents outnumber humans.
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