Top Front End Developer Jobs in Denver & Boulder, CO

Designs, develops, tests, deploys, operates, and maintains scalable full-stack software products. Builds React-based enterprise applications, writes production-ready code, performs code reviews, improves reliability and performance, integrates APIs, and follows security, compliance, accessibility, and DevOps practices. Collaborates across teams using agile methods, analyzes failures, prioritizes work, and contributes to technology transformation and continuous improvement.

Develop and maintain front-end web applications and cloud-native microservices for mission management systems. Build user interfaces with JavaScript and TypeScript, write automated tests, deploy through DevSecOps pipelines, troubleshoot defects, and collaborate within an Agile Kanban team. The role is fully onsite in a SCIF and requires TS/SCI clearance with CI polygraph eligibility or willingness to complete the polygraph.

Lead the strategic direction of frontend engineering, architecture, tooling, and standards. Build accessible, high-performing React or Angular applications, component libraries, design systems, deployment pipelines, and testing strategies. Drive modernization, performance, accessibility, and developer-experience initiatives while collaborating with product and design teams. Mentor engineers, influence cross-team technical decisions, and contribute across the full stack when needed. The role is remote, requires U.S. citizenship and the ability to obtain Public Trust 6C, and involves up to 10% travel.

Own end-to-end development of customer-facing web platform features, emphasizing React and TypeScript frontend development while contributing to Python backend services. Translate product concepts and designs into reusable, intuitive UI components, partner with Product and Design, engage directly with users, and use AI-powered tools to accelerate development while maintaining code quality and performance.

Develop and maintain performant frontend web applications for real-time, mission-critical data. Responsibilities include UI architecture, API integration, responsive design, automated testing, performance optimization, security remediation, code reviews, Agile collaboration, documentation, and frontend reliability improvements.

Build responsive, high-performance React and Next.js interfaces for cloud workspace creation, resource management, billing, monitoring, and developer tools. Integrate applications with backend APIs and real-time services, improve performance and accessibility, and develop reusable components. Collaborate with backend engineers and product teams while contributing to feature ownership and product decisions.

Build and maintain responsive, accessible web interfaces using React, HTML, CSS, and JavaScript/TypeScript. Integrate applications with REST APIs and back-end services, implement WebSocket features, optimize Core Web Vitals, and develop reusable design-system components. The role also involves Node.js tooling, cross-browser compatibility, code reviews, QA collaboration, and front-end testing.

Build and ship healthcare software across the frontend, API, and database using React, TypeScript, Next.js, tRPC, Prisma, and related technologies. Own features end to end, prototype with AI tools, test with patients and care teams, and improve performance, accessibility, reliability, and scalability. Collaborate closely with company leadership in a fast-paced startup environment while developing trustworthy automation for healthcare delivery.

Develop and maintain responsive frontend interfaces, dashboards, reports, and enterprise web applications. Translate requirements into functional user interfaces, build UI and automated tests, troubleshoot and optimize performance, implement REST API integrations and routing, and collaborate with backend developers and testers. The role requires React, JavaScript, Redux, Node.js, and related frontend technologies, with preferred experience in dashboards, reporting, testing, AWS, and government applications.

Build and maintain responsive, accessible front-end interfaces using React, React Native, HTML, CSS, and Shopify. Apply UX/UI principles, collaborate with designers and multidisciplinary teams, provide clear technical feedback, and independently deliver high-quality work on complex technology or AI-related projects. Contractors complete output-based tasks and must meet weekly minimum submission requirements, with an expected start within 24–48 hours of onboarding.

Design and build user-facing features for a live video chat and multiplayer gaming platform. Collaborate with designers and product managers, lead technical quality and scalability efforts, rapidly experiment, and solve customer problems through deep user understanding. The role focuses on front-end architecture using TypeScript and React, with Node.js proficiency and strong CSS fundamentals.

Lead frontend feature releases and own user experience, performance, testing, and production health for a React and TypeScript dental practice management platform. Collaborate with backend engineers using Java Spring Boot, develop AI-powered interfaces, integrate AI tools such as Claude, participate in code reviews, improve team efficiency, and estimate development work for timely delivery.

Develop and maintain responsive Angular web applications using Angular 19+, Signals, Reactive Forms, and modular component architecture. Build complex forms, integrate REST APIs with RxJS, optimize change detection and performance, and create unit tests with Vitest or Jest. Collaborate with design, backend, and product teams, troubleshoot cross-browser issues, participate in code reviews, and follow modern front-end development practices.

Design, develop, and enhance custom SAP Fiori/UI5 applications; configure Fiori Launchpad; integrate OData services; perform UI debugging, performance optimization, code reviews, unit testing, and documentation while collaborating with backend and functional teams.

Volunteer Principal Front End Developer to build React/React Native web and mobile features, mentor engineers, implement scalable full‑stack solutions, ensure cross‑browser compatibility and testing, work with Node/MongoDB/AWS, attend weekly standups, and support a fundraising launch. Minimum 4 hours/week commitment.

Design, build, and optimize responsive, high-performance front-end interfaces for a Web3 DEX using modern JavaScript frameworks and TypeScript. Collaborate with designers, product, and back-end teams to integrate blockchain APIs and smart contracts, mentor junior developers, troubleshoot issues, and contribute to mobile-first/PWA development while ensuring scalability and maintainability.

Build and maintain responsive, accessible React/NextJS web interfaces and support Chrome extension development (Manifest V3). Integrate with backend APIs or WebSockets, optimize performance, write tests, perform code reviews, monitor and document extension and web app behavior, and collaborate with cross-functional teams.

Build, test, and optimize responsive web applications using Next.js and React. Collaborate with designers and back-end developers, implement UI/UX designs, write clean maintainable code, and debug front-end issues to ensure high performance across devices and browsers.

Build and own frontend applications for DeFi products using Next.js and TypeScript. Develop reusable component libraries and design systems, integrate Solana programs and wallet infrastructure, and translate complex financial concepts into accessible interfaces. Own performance, reliability, observability, testing, analytics, and end-to-end feature delivery while collaborating with protocol engineers, designers, and product teams.

Architect and build a high-performance trading platform for active traders. Develop responsive web interfaces integrating real-time market data, low-latency execution workflows, and advanced trading tools. Collaborate with cross-functional engineering teams on large-scale initiatives, emphasizing scalability, performance, API quality, maintainability, developer experience, and end-user usability.

Lead the evolution of Seeq’s frontend infrastructure, including React systems, component libraries, state management, styling architecture, and reusable application patterns. Drive large-scale refactors, improve developer experience, ensure accessibility and performance, evaluate open-source tools, and establish technical standards adopted across teams. Collaborate with designers, product teams, and engineers through architecture reviews, documentation, code reviews, mentoring, and cross-team delivery.

Own the frontend architecture and implementation of a greenfield legal technology product using React and TypeScript. Build complex, secure, role-aware workflows; establish component, state-management, routing, form, validation, accessibility, performance, and testing standards; integrate backend APIs and AI-enabled capabilities; and provide technical guidance to frontend developers.

Build and ship frontend features for a financial marketplace using React and Next.js. Collaborate with product, design, and backend engineers; contribute to architecture, component design, code quality, tooling, and the shared component library. Own work from design through delivery, participate in pairing and code reviews, and use AI-assisted development tools thoughtfully.

Lead frontend engineering for large-scale React web applications. Architect application patterns, structure, libraries, and coding standards; build React applications end to end; conduct code reviews; mentor engineers; promote performance, scalability, and maintainability; and collaborate with designers, product managers, and technical and non-technical stakeholders.

Lead front-end engineering for enterprise transportation applications using React, TypeScript, and Material UI. Responsibilities include front-end architecture, reusable component development, accessibility, responsive design, API integration, SQL troubleshooting, testing, CI/CD, code reviews, mentoring, Agile planning, modernization, and production support. The role independently leads features from requirements through deployment while collaborating with designers, product owners, analysts, engineers, testers, DevSecOps teams, and government stakeholders.