Top Senior Front-End Engineer Jobs in Boston, MA

Own frontend domains end to end, including architecture, implementation, testing, production quality, performance, accessibility, and security. Set technical direction, design reusable component systems, establish testing strategies, diagnose complex browser and production issues, and partner with Product, Design, QA, and engineering teams. Mentor engineers, review consequential changes, and use AI-first development practices while maintaining accountability for shipped software.

Develops modern, responsive, accessible front-end interfaces, reusable component libraries, templates, and interactive features for federal and DoD-aligned IT environments. Collaborates with UX, backend, CMS, and product teams on API integrations, performance optimization, accessibility compliance, cross-browser troubleshooting, documentation, code reviews, and Agile delivery. Requires an active Secret clearance, bachelor’s degree, and at least seven years of front-end development experience.

Build and improve ClickUp’s core product experiences using Angular and React. Responsibilities include architecting reusable frontend code, collaborating with product, design, backend, integrations, and QA teams, improving performance and usability, maintaining unit and integration tests, resolving complex bugs, following state-management patterns, and mentoring teammates in a fast-paced environment.

Build and improve frontend interfaces for DogByte and other internal products used by veterinary hospitals. Own projects from problem framing through production release, collaborate with Design and Product, uphold accessibility and performance standards, evolve shared components and design systems, review technical work, and contribute to backend or full-stack development as needed. Apply AI tools thoughtfully across development workflows while maintaining quality and reliability.

Lead frontend design and implementation for patient and physician products, shape frontend architecture (design systems, state, testing, performance), integrate AI/LLM features with backend/ML teams, and deliver polished, accessible, high-performance interfaces in a hybrid NYC/Boston environment.

Build and own LangChain’s React component library and design system. Develop accessible, reusable UI components; translate design tokens and interaction patterns into code; create tooling for theming, versioning, testing, visual regression, and component discovery; and optimize build performance, bundling, dependency management, and package versioning. Collaborate closely with designers, product engineers, and platform teams to maintain a consistent, high-quality frontend foundation.

Design and build user-facing components for an AI-native cloud platform, ensuring scalability and performance, mentoring engineers, and optimizing web interfaces.

Design, build, test, and maintain scalable, responsive front-end applications (React/TypeScript). Collaborate with cross-functional teams to implement AI-integrated UIs, optimize performance, and own frontend lifecycle including unit, integration, and end-to-end testing.

Build and refine front-end experiences for web and mobile: onboarding, checkout, gallery features, design system and enterprise dashboard. Collaborate closely with designers and PMs, ship fast, maintain aesthetic quality, and iterate with user feedback using React, Next.js and TypeScript.

Lead end-to-end front-end development for an enterprise Agentic AI platform. Design interactive, explainable UIs that render streaming LLM outputs, code citations, dependency graphs and authoring workflows. Build real-time experiences with WebSockets/streaming APIs, ensure traceability to source code, collaborate with AI engineers and designers, and drive accessibility, performance, and observability across a FedRAMP-aligned federal deployment.

Own and build the JTX frontend across web and mobile: real-time order books, charts, order entry, positions, wallet/signing flows. Optimize for low-latency streaming data, performance, security, and cross-platform consistency while making long-term architectural decisions and shipping rapidly.

Work with ASIC Infrastructure to enhance design productivity, deploy AI toolsets at scale, and improve CI systems while solving complex issues.

Lead development of interactive React front-ends with Chakra UI and Mapbox, build data visualizations (Plotly/ApexCharts), optimize performance for large and real-time datasets, enforce front-end best practices, mentor engineers, and collaborate with product, design, and backend teams to deliver accessible, responsive interfaces.

Design and develop web applications, mentor teammates, shape architectural decisions, write clean code, conduct testing, and troubleshoot issues.

Build and maintain a polished web portal for a premium banking and travel rewards platform using React. Collaborate with designers and engineers on feature scope and product direction, participate in code and design reviews, write well-architected code, tests, and documentation, establish frontend architecture standards, and mentor team members. The role also involves database and API integrations in a fully remote startup environment.

Lead end-to-end implementation of high-fidelity, performant, and accessible frontend features for a realtime collaborative visual canvas. Translate designs into polished interactions, optimize performance and accessibility, collaborate with PMs, designers, and backend engineers, and shape frontend best practices and design systems.

Lead frontend architecture and technical strategy for a collaborative work platform. Build scalable React/TypeScript applications, design systems, real-time collaboration (sync, offline, serialization), optimize performance and observability, mentor engineers, and collaborate with Product, Design, and Backend teams to deliver high-quality, maintainable user experiences.

Develop and maintain web application user interfaces using Vaadin and front-end technologies. Apply UI fundamentals (including Fitts' law), refactor enterprise applications, collaborate with clients, and mentor/train other front-end developers.

Develop and enhance user-facing features for an LLM observability platform using React and TypeScript. Build reusable components and front-end libraries, translate designs into performant UI code, optimize cross-device/browser performance, and collaborate with backend engineers and designers to improve usability.

Founding-team senior engineer to architect and build core platform components. Work with CEO/CTO to develop scalable distributed backend systems and frontend using React, Node.js and TypeScript. Implement solid coding practices, testing, CI/CD, and agile workflows while iterating rapidly in an early-stage fintech startup.

Own and evolve the front-end architecture for a high-throughput, real-time trading app using Next.js, React, and TypeScript. Build pixel-accurate, accessible, responsive UIs under strict performance budgets; optimize rendering, state management, data flow, and bundle size for sub-second interactions. Integrate with REST and WebSocket APIs, lead end-to-end feature development, set engineering standards, mentor engineers, and contribute across the stack when needed.

As a Senior Frontend Engineer, you'll build and maintain a fraud prevention platform UI using ReactJS, collaborating with backend teams and ensuring code quality through tests and CI/CD processes.

The Senior Full Stack JavaScript Developer will build and maintain user interfaces using React and Next.js, integrate with Node.js backends, and guide other developers. Responsibilities include ensuring accessibility, performance, and reliability of features, engaging in code reviews, and collaborating closely with product teams.

Build and maintain production-grade React+TypeScript web interfaces for data-intensive, real-time AI products. Own end-to-end frontend features, optimize UI performance for large datasets, collaborate with design and backend teams, establish frontend best practices, improve architecture and tooling, and resolve production issues across browsers and devices.

Design and implement pixel-perfect, high-performance web applications from wireframes to production. Collaborate with designers, PMs, and engineers, iterate on architecture and best practices, explore AI/ML integrations, and contribute to a collaborative engineering culture.