Founding Engineer ($150K–$250K + Equity) Building Inboxes for AI Agents
CoffeeSpace · San Francisco, CA
Apply & track with Apply EdgeAbout the jobThis role is being recruited by CoffeeSpace on behalf of an anonymous AI infrastructure startup building the identity and communication primitive for AI agents.We’re identifying a small number of exceptional founding engineers from our network. If there’s a strong fit, we’ll introduce you directly to the founding team.
They focus on AI, API SDK, devtools, and B2B industries. The company has raised $6M in seed funding from elite angels including Paul Graham and Dharmesh Shah. The team consists of 8 people, with 6 engineers from prestigious backgrounds such as Optiver, NVIDIA, and Amazon.The company is experiencing hypergrowth, doubling user count every two weeks since January and achieving 20–30% month-over-month revenue growth.About the roleAs a founding engineer, you will be responsible for building and designing APIs and backend infrastructure that AI agents use to communicate, authenticate, and operate. This involves owning projects from inception to production, with a focus on backend development.You will work across the full stack when needed, and will be expected to proactively pitch growth experiments or product ideas. Additionally, you will occasionally support enterprise customers with custom deployments and write clear, maintainable code and documentation.What You’ll DoBuild and design core product APIs and backend infrastructureOwn 0→1 projects end-to-end, including customer requirements, system design, and production rolloutWork across the full stack, primarily on backend systemsProactively pitch growth experiments and product ideasSupport enterprise customers with custom deploymentsWrite clear, maintainable code and strong technical documentationWhy This Role Is CompellingYou’ll have greenfield ownership over projects, scoping, building, and shipping themThe role is backend-first but allows exploration into growth, product, or forward deployment workCompetitive compensation with additional perks like Equinox membership and free mealsThe Ideal Candidate0–5 years of experience, with flexibility for exceptional candidates with moreExperience shipping production software at a pedigreed companyComfortable owning projects end-to-end in a fast-paced, early-stage environmentExperience with TypeScript, REST APIs, distributed systems, cloud infrastructure, and email protocolsThis Role Is NOT For You IfYou require visa sponsorshipYou prefer a stable, clearly scoped role without ambiguityYou are not comfortable working on-site in San FranciscoNext steps1. Apply via this LinkedIn job post2. We’ll review and reach out if there’s a strong match3. If aligned, we’ll introduce you directly to the team4. If this role isn’t the right fit, we may suggest and make introductions to other high-signal startup roles we’re recruiting for, always with your permission.A quick note on authenticityThis is a real, active role that CoffeeSpace is recruiting for in close partnership with the hiring team. We don’t post speculative roles and work directly with teams on their actual hiring needs.