Principal Front End Engineer Jobs (NOW HIRING)

Circuit is the AI execution layer for the physical economy.

Industrial and manufacturing enterprises run on expertise: the hard-won knowledge of how complex products are engineered, configured, sold, and supported. That expertise is scarce, slow to transfer, and walking out the door as a generation of experts retires. It lives in PDFs, spreadsheets, and the heads of a few people, and the hardest technical decisions wait on whoever happens to know.

Circuit puts expert judgment in everyone's hands. We capture how the best people make critical technical decisions and turn it into agents that do the judgment-heavy work, so anyone, regardless of skill level, can make the right call, from quote to install and support, with the accuracy these environments demand.

Circuit is built by operators. Our leadership team has built and scaled real industrial companies, and we are already live in production with category-leading manufacturers. We are not bolting AI onto an old playbook. We are building the layer that runs the last mile of how the physical economy executes.

As a Staff Frontend Engineer at Circuit, you will be responsible for building high-quality, user-facing experiences in our core web application. You’ll work closely with Product, Design, and Engineering peers to turn product direction into intuitive, performant, and accessible interfaces.

This role is highly collaborative and hands-on. You’ll contribute to frontend architecture and technical decision-making alongside other engineers, help set quality and engineering standards through example, and mentor teammates through code reviews and shared problem-solving. You’ll be expected to operate with autonomy, navigate ambiguity, and consistently deliver production-ready work that balances user experience, technical excellence, and business impact.

We're also an agent-native engineering team. Engineers routinely run Claude Code and Cursor against our monorepo and we invest in the context, custom commands, and skills that make them effective. You should be excited to work this way: orchestrating agents for scoping, implementation, and triage, while owning the judgment, architecture, and quality bar yourself.

• Design, build, and maintain core user-facing features in Circuit’s web application.

• Translate product requirements and design direction into polished, responsive, and accessible UI.

• Contribute to frontend architecture, patterns, and technical decisions in collaboration with engineering peers.

• Leverage agentic tools (Claude Code, Cursor) throughout the development cycle — scoping, implementation, testing, and bug triage — and help improve the team's shared agent tooling and context.

• Own features end-to-end, from implementation through testing, QA, and production release.

• Write and maintain unit, integration, and end-to-end tests to ensure long-term reliability.

• Instrument, monitor, and debug production frontend issues using observability tooling (Datadog RUM, tracing, structured logging), and use real-user data to drive performance improvements.

• Participate actively in technical discussions, design reviews, and planning sessions.

• Provide thoughtful code reviews and mentorship to support team-wide quality and growth.

• Collaborate closely with Product and Design to clarify requirements, surface tradeoffs, and improve UX.

• Identify and drive incremental improvements to performance, accessibility, developer experience, and frontend tooling.

• Manage individual priorities and deadlines while maintaining a high standard of execution.

• 7+ years of professional frontend or full-stack engineering experience building and shipping production web applications.

• Proven experience operating as a staff or principal-level individual contributor within a collaborative engineering team.

• Experience collaborating closely with Product and Design partners to iterate on UX and balance technical and product tradeoffs.

• Track record building AI-powered product surfaces: chat interfaces, streaming responses, optimistic/incremental rendering, and designing UX around non-deterministic outputs.

• Demonstrated ability to take loosely defined product requirements and turn them into high-quality, production-ready solutions.

• A track record of improving code quality, developer experience, or frontend practices through example and influence rather than authority.

• Comfort operating in ambiguous, fast-moving environments and managing individual priorities without heavy process or oversight.

• Fluent with agentic coding tools (Claude Code, Cursor, or similar) — comfortable delegating implementation to agents, reviewing and validating AI-generated code, and knowing when not to.

• Experience working with performance, reliability, and maintainability concerns in large or evolving frontend codebases.

• Advanced proficiency in TypeScript, React, HTML, and CSS, with a track record of building complex, user-facing features.

• Strong proficiency with CSS Modules and component-scoped styling approaches.

• Experience with modern state management patterns using React Query for server state and Zustand for client state.

• Experience building and maintaining shared component libraries with Storybook, visual regression testing (Chromatic), and accessibility tooling.

• Strong experience designing and implementing responsive, accessible interfaces that follow modern UX and accessibility standards.

• Experience with monorepo tooling and workflows (Turborepo, Nx, or similar) and managing dependencies across multiple frontend packages.

• Hands-on experience writing and maintaining unit, integration, and end-to-end tests (e.g., Playwright, Vitest, React Testing Library).

• Experience building and consuming RESTful APIs, with understanding of API design best practices and error handling patterns.

• Hands-on experience with CI/CD pipelines, GitHub Actions, and deployment automation. Experience with Docker, infrastructure tooling, and DevOps practices is highly valued.

• Familiarity with modern development workflows and tooling, including Git, Linux-based environments, and containers.

• Comfortable working across the full stack when needed — familiarity with backend concepts, databases, and API development is a plus.

• Working knowledge of Go and experience with Go, Docker, Kubernetes, and cloud platforms (AWS, GCP, Azure) is a plus.

• Familiar with integrating authentication/identity providers.

• Skilled at building the scaffolding that makes agents effective: authoring CLAUDE.md/context files, custom slash commands and skills, MCP integrations, or running agents on remote/headless dev environments.

• Awareness of emerging standards like A2UI, AG-UI, MCP Apps and similar.

If you've built in this space, we'd love to hear about it. Relevant experience might include:

• Building performant, interactive data visualizations with libraries such as D3.js, Recharts, Nivo, or similar

• Working with WebGL, Three.js, Babylon.js, or other 3D rendering tools in a browser context

• Designing navigation patterns and interaction models for complex visual environments (e.g., graph traversal, spatial zoom/pan, scene hierarchy)

• Thinking about rendering performance at scale — large datasets, real-time updates, level-of-detail strategies

• Background in game development or interactive simulation — the mental models transfer well

• Strong problem-solving abilities and comfort operating in ambiguity.

• Excellent communication skills, with the ability to explain technical concepts to non-technical stakeholders.

• Highly collaborative across Product, Design and Engineering.

• High ownership mentality with a bias toward action and results.

• Adaptable, curious, and energized by the pace of an early-stage startup.

• Low-ego collaborator who values feedback, iteration, and shared success.

• High-caliber team of seasoned manufacturing and AI leaders

• Help create a category-defining platform transforming how manufacturers sell, support, and innovate

• Competitive compensation, meaningful equity, and employer-paid benefits

• Flexible PTO and access to the latest AI tools

• A values-driven culture that rewards ownership, curiosity and velocity

If you're a hands-on, staff-level frontend engineer who loves turning ambiguous product direction into enterprise-grade, production-ready interfaces, we'd love to hear from you.

We are an equal-opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.