Staff Fullstack Engineer, AI Agents

11x; San Francisco (CA); On-site; USD 150,000 - 250,000; Full time

Job summary

11x in San Francisco is seeking a Staff Software Engineer with deep fullstack expertise to lead architecture and product development for AI-powered autonomous digital workers.

You will mentor engineers, set engineering standards, and collaborate with the CTO and cross-functional teams to deliver production-grade systems in a fast-moving AI-native environment. This hands-on leadership role requires shaping design choices, improving developer efficiency, and ensuring reliability.

Qualifications

• 6+ years of software engineering experience with leadership on complex projects.
• Expertise with modern fullstack frameworks: Typescript, React, NextJS, NodeJS.
• Proven ability to ship scalable systems in fast-growing environments.
• Strategic thinker balancing speed and quality while guiding technical vision.

Responsibilities

• Architect, build, and scale fullstack systems for autonomous AI agents.
• Lead technical decisions across projects for long-term scalability and reliability.
• Evaluate new technologies, model APIs, and prompting strategies.
• Collaborate with design, product, and GTM teams to define roadmaps.
• Drive internal engineering standards through mentorship and code reviews.

Skills

Leadership

Architectural design

Mentoring

Typescript

React

NextJS

NodeJS

Tools

Typescript

React

NextJS

NodeJS

Job description

About The Role

We’re looking for a Staff Software Engineer with deep fullstack expertise and a passion for building ambitious AI-powered systems. In this role, you’ll operate as a technical lead—driving architecture, product development, and internal standards for one of our flagship autonomous digital workers.

You’ll collaborate closely with our CTO, cross‑functional teams, and model providers to translate complex ideas into elegant, production‑ready software. This is a hands‑on leadership role where you’ll influence system design, mentor other engineers, and set the bar for engineering quality in a fast‑moving, AI‑native environment.

What You’ll Do

• Architect, build, and scale fullstack systems that support autonomous AI agents in production.
• Lead technical decision‑making across projects—ensuring long‑term scalability, reliability, and developer efficiency.
• Evaluate new technologies, model APIs, and prompting strategies to enhance agent performance and alignment.
• Collaborate cross‑functionally with design, product, and GTM teams to define roadmaps and prioritize development.
• Drive internal engineering standards through mentorship, documentation, and code reviews.

What We’re Looking For

• 6+ years of experience in software engineering, with demonstrated leadership on complex technical projects.
• Strong command of modern fullstack frameworks—especially Typescript, React, NextJS, and NodeJS.
• Track record of shipping scalable systems in high‑growth or startup environments.
• Strategic thinker who can balance speed and quality while driving technical vision.
• Bonus: experience with LLMs, agent orchestration frameworks, or AI infrastructure.

Base salary range: $150,000 – $250,000

• Final offer will be based on a variety of factors, including role level, relevant experience, skills, and job‑related expertise.

11x is an equal opportunity employer and does not discriminate on the basis of race, gender, sexual orientation, gender identity/expression, national origin, disability, age, genetic information, veteran status, marital status, pregnancy or related condition, or any other basis protected by law.