Senior Front End Engineer

We're looking for an exceptional Senior Frontend Engineer to join our founding team and lead our frontend engineering efforts. You'll work directly with our CTO to build sophisticated, responsive interfaces that make complex AI capabilities accessible to enterprise developers. This is a hands-on technical leadership role where you'll architect our frontend systems, establish engineering best practices, and mentor junior engineers as we scale.

You'll be the frontend technical authority-making critical architectural decisions, building new platform features, refactoring existing systems, and defining how we approach frontend engineering at Blitzy. You're equally comfortable debugging a complex state management issue, architecting a component library from scratch, or mentoring a junior engineer through their first major feature.

What Success Looks Like

• You architect and implement sophisticated frontend solutions that handle complex state management, real-time AI agent updates, and intuitive developer workflows.
• You establish frontend engineering standards, patterns, and best practices that scale with our growing team.
• You build responsive, performant interfaces that work seamlessly across browsers and devices while maintaining sub-second interaction speeds.
• You refactor and modernize existing frontend code, eliminating technical debt while shipping new features.
• You make architectural decisions that balance immediate product needs with long-term scalability and maintainability.
• You mentor junior frontend engineers, conducting code reviews and elevating the team's technical capabilities.
• You collaborate closely with product, design, and backend teams to deliver cohesive user experiences.
• You evaluate and introduce new technologies and frameworks that improve our development velocity and product quality.
• You maintain high standards for code quality, performance, testing, and accessibility.
• You become a trusted technical advisor to leadership on all frontend architecture decisions.

Areas of Ownership

As our Senior Frontend Engineer and technical lead, you'll own:

• Frontend architecture and technical decision-making for our core platform.
• Refactoring existing frontend systems to improve performance and maintainability.
• Building new platform features that showcase our AI capabilities to enterprise users.
• Establishing component library and design system foundations.
• Setting up testing frameworks and CI/CD pipelines for frontend.
• Code review processes and engineering standards.

Growing Responsibilities

• Mentoring and providing technical guidance to junior frontend engineers.
• Performance optimization and monitoring systems.
• Frontend infrastructure and build tooling improvements.
• Cross-team collaboration on API design and integration patterns.
• Technical documentation and onboarding processes.

Long-term Vision

• Scaling the frontend engineering team and practices.
• Defining frontend engineering hiring standards and interview processes.
• Contributing to product and technical strategy discussions.
• Building advanced features like real-time collaboration, AI-powered UIs, and developer tools.

Do you have experience in UI implementation?, * 10+ years of frontend development experience with a proven track record of building complex, production-grade applications.

• Expert-level knowledge of modern JavaScript/TypeScript with deep understanding of language features, patterns, and best practices.
• Deep expertise in React.js and its ecosystem including hooks, context, performance optimization, and modern patterns.
• Strong understanding of state management (Redux, MobX, Zustand, or similar) and when to apply different patterns.
• Experience with modern build tools (Webpack, Vite, esbuild, etc.) and their configuration.
• Proven ability to architect scalable frontend systems that handle complexity while remaining maintainable.
• Experience with responsive design and cross-browser compatibility, ensuring consistent experiences across devices.
• Strong understanding of web performance optimization including bundle size, rendering performance, and Core Web Vitals.
• Experience with frontend testing frameworks and methodologies (Jest, React Testing Library, Playwright, Cypress).
• Track record of technical leadership including mentoring, code reviews, and establishing engineering standards.

What Makes You Stand Out

• Experience with GraphQL and real-time data handling (WebSockets, Server-Sent Events).
• Knowledge of WebAssembly and its applications in frontend development.
• Experience with micro-frontend architectures or monorepo management.
• Contributions to open-source projects, especially in the React or JavaScript ecosystem.
• Experience with advanced animations and complex UI interactions (Framer Motion, React Spring).
• Deep knowledge of accessibility standards (WCAG) and practical implementation.
• Experience with design systems at scale and component library architecture.
• Speaking engagements or technical writing demonstrating thought leadership.
• Experience at high-growth startups or in technical leadership roles.
• Experience working effectively with AI coding tools (Blitzy, Copilot, Cursor, Claude, etc.) to accelerate frontend development without compromising code quality or engineering standards.
• Proven ability to review and validate AI-generated code-identifying subtle logic errors, security gaps, and style inconsistencies that automated tools routinely miss.
• Track record of writing precise, reusable prompts for frontend tasks including component generation, test writing, refactoring, and PR documentation to get consistent, production-ready output.
• Experience establishing team-wide processes for AI-assisted development-defining when to use AI, how to review its output, and how to integrate it cleanly into existing PR and code review workflows.

Pulled from the full job description

• Parental leave
• Health insurance
• 401(k) matching
• Paid time off
• Vision insurance
• Dental insurance, * Direct collaboration with the CTO and founders-your architectural decisions will define how the product scales.
• You'll build interfaces for one of the most technically ambitious AI platforms in enterprise software development.
• Competitive compensation ($140K-$165K) with significant equity upside at an early-stage, high-growth startup.
• Comprehensive benefits including health, dental, vision, 401(k) with match, generous PTO, and parental leave.
• A clear path to Staff Engineer, Principal Engineer, or Engineering Manager based on your strengths.
• Modern in-person office in Cambridge's innovation hub at 1 Kendall Square with a strong team culture.

Led by two pioneering co-founders we are one of the fastest growing companies in the U.S., creating our own category of enterprise autonomous software development. We automate thousands of hours of software development for our customers, which includes strong representation within the Fortune 500. How we work: We move Blitzy Fast: Time is both our company's and our clients' most precious asset. We move quickly and decisively to innovate internally and deliver exceptional software externally. Championship Mindset: We operate like a professional sports team. We win as a team by holding ourselves and each other to high standards, collaborating in-person, and remaining focused on the mission. Passion for Invention: We're pushing the frontier of what's possible, requiring constant innovation and iteration. We Work for the Customer: We focus on delivering outsized value to the customers we work with and expanding those relationships into deep, meaningful partnerships. We believe in being 'everyday athletes'-taking care of ourselves so we can bring our best minds to work. We promote great sleep, movement, and restorative activities for optimal mental performance. It makes for a happier and more productive team. Blitzy is an equal opportunity employer committed to building a diverse and inclusive team. We believe different perspectives make us stronger.