Founding Engineer @ x1

X1 • San Francisco, CA

2d

About The Position

We're building x1. AI has made writing code much easier. Shipping complete, reliable products is still the bottleneck. x1 focuses on that gap: helping people go from an idea and some code to a working iOS app that can actually be shipped and maintained. Why this problem matters Apple reviewed ~7.7 million App Store submissions in 2024 ~1.9 million were rejected (~25%) The most common reasons were not “bad ideas” or “bad code,” but broken flows, missing setup, and integration issues At the same time, AI tools are dramatically increasing the number of people who can write code So the top of the funnel is growing fast. The number of apps that successfully ship is not. We're building for that mismatch. What you'll work on This is a founding-level role. You'll work directly with the founder and own meaningful parts of the product. The work spans: End-to-end product flows that turn ambiguous user intent into concrete implementation steps Full-stack systems (frontend, backend, APIs, data models) Native iOS development (Swift, SwiftUI, Xcode) Integrations with modern AI tooling Making systems reliable enough that users can actually finish and ship You'll make early architectural decisions, revisit them as we learn, and see the impact directly in user outcomes.

Requirements

• Full-stack experience (e.g. TypeScript/React or similar + backend systems)
• Native iOS experience (Swift/SwiftUI), ideally with shipped apps
• Comfort owning features end-to-end
• Ability to reason about tradeoffs, edge cases, and UX
• Bias toward shipping and iteration

Responsibilities

• End-to-end product flows that turn ambiguous user intent into concrete implementation steps
• Full-stack systems (frontend, backend, APIs, data models)
• Native iOS development (Swift, SwiftUI, Xcode)
• Integrations with modern AI tooling
• Making systems reliable enough that users can actually finish and ship
• Make early architectural decisions

Benefits

• Very early team
• YC-backed
• Real equity and ownership
• Direct exposure to users and real feedback
• Opportunity to work on a product aimed at a large and growing market: 50M+ registered Apple developers Millions of new builders entering via AI tools
• This role is for someone who wants responsibility early and prefers building over process.

What This Job Offers

• Job Type: Full-time
• Career Level: Entry Level
• Education Level: No Education Listed