About the Role
We're a Y Combinator–backed EdTech startup on a mission to help people acquire languages and connect across cultures — and we're hiring a Founding Full-Stack Engineer to join our small, tight-knit founding team in San Francisco. This is a rare opportunity to shape the product, architecture, and engineering culture from the ground up at a fast-growing, mission-driven company in the language learning space.
You'll work in-person with the founders every day, own large swaths of the codebase, and ship features end-to-end — from backend services and data models all the way through mobile UI and deployment. If you thrive at the intersection of great craft, AI-driven product experiences, and genuine mission, this role is for you.
What You'll Do
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Collaborate in-person with the founding team daily in San Francisco.
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Own large parts of the codebase across mobile, web, backend, infrastructure, and AI.
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Ship full end-to-end product features — from backend logic through UI to deployment.
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Build high-performance mobile experiences in React Native.
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Implement and maintain video streaming and HLS pipelines.
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Develop AI-driven learning experiences using LLMs and audio/video models.
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Build and maintain backend services in Go.
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Design data models, schemas, and performance optimizations in PostgreSQL.
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Improve developer tooling, CI/CD pipelines, and observability.
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Influence foundational architecture, engineering culture, product direction, and UX.
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Move fast while maintaining a strong commitment to quality, craftsmanship, and reliability.
What We're Looking For
Must-haves (dealbreakers):
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3+ years of professional software engineering experience delivering end-to-end features across mobile, web, and backend systems.
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Strong experience building backend services in Go (Golang) with PostgreSQL, including data modeling and performance optimization.
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Experience delivering mobile apps using React Native (Expo) or native iOS/Android development.
Required skills:
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Strong TypeScript fundamentals and solid foundations in HTML, CSS, JavaScript, and REST APIs.
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Deep understanding of at least two compiled languages, including Go and one other (e.g., Swift, Kotlin, C++, Java, C#).
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Writes testable code with unit, integration, and end-to-end tests (mocks, pure functions).
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Experience with at least one scripting language (Python or Ruby) for tooling and automation.
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Comfortable with Unix-based systems, Git, and terminal workflows.
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Excellent debugging skills using Chrome DevTools, RN profiler, or Xcode Instruments.
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Familiarity with video streaming (HLS) and building AI/LLM-driven features.
Nice to have:
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Cloud provider experience (AWS, GCP, Azure, or DigitalOcean).
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CI/CD experience with GitHub Actions.
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Profiling and performance optimization experience.
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Prior startup or founder experience.
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Comfortable using AI development tools (Cursor, Copilot, GPT, Claude, etc.).
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Speaks multiple languages or is actively learning one; familiarity with immersion-first language learning is a big plus.
Compensation & Benefits
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Salary: $150,000 – $200,000 USD annually
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Meaningful early-stage equity
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Visa sponsorship available when needed
Location
This role is fully on-site in San Francisco, CA. You'll work in person with the founding team every day. Candidates must be willing and able to commit to full-time, in-person work in San Francisco.
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