Software Engineer, Frontend Infrastructure

Replit is the fastest way to turn ideas into software. With our powerful AI-powered Agent and Assistant, anyone can create and launch apps from natural language in just one click. Build and deploy full-stack applications directly from your browser—no setup required. Never written a line of code in your life? No problem. Replit makes software creation accessible, collaborative, and lightning-fast. Join us in our mission to empower the next generation of builders.

About the role

As a Software Engineer on the Frontend Infrastructure team, your mission is to build powerful tools that help product engineers iterate rapidly on the Agent experience and directly enhance the core Agent itself. You’ll bridge the gap between the AI team—focused on the core Agent logic—and the Product team—crafting a delightful user experience—enabling both groups to excel within their specialties. This role blends infrastructure, product engineering, developer experience, and beyond.

Despite our name, our team has evolved beyond pure frontend work - we tackle complex challenges across the full stack, from browser-based interfaces to high-performance backends to Linux systems engineering. The ideal candidate is a versatile engineer who enjoys working as a generalist while bringing deep expertise in at least one domain.

In this role you will :

Design a collaborative "Multiplayer Computer" that lets humans and AI agents work together on shared shells, filesystems, and state—conflict-free and in real time.

Build high-throughput backend applications and services.

Create tooling that helps AI systems minimize mistakes through static analysis and deterministic techniques.

Develop infrastructure (frontend & backend) that empowers product engineers to rapidly ship delightful user experiences.

Support sophisticated user interfaces, including terminals, code editors, window-management systems, and innovative experiences that require both creativity and algorithmic skill.

Required skills and experience :

2+ years of professional expertise in at least one of the following :

Developing rich browser-based applications.

Building high-throughput backend services.

Creating frontend infrastructure used by 100+ engineers.

Shipping your own products and engaging directly with users.

Someone who values simplicity and pragmatism—you think radically but ship incrementally.

Self-directed and comfortable working autonomously.

Nice to have :

Experience with low-level Linux system components.

Experience building AI-powered tooling or products.

Familiarity with IDEs, terminals, LSPs, or other developer-centric tools.

Experience with collaborative editing technologies such as Operational Transforms (OT), CRDTs, or the inner workings of Git.

Contributions to popular open-source JavaScript frameworks and libraries.