Top Senior Front End Developer Jobs in Portland, ME

Architect and build a high-performance, low-latency trading web platform. Integrate real-time market data and execution workflows, collaborate cross-functionally on large initiatives, and deliver scalable, performant, user-focused frontend applications with strong attention to API design, tooling, and developer experience.

Lead frontend architecture and strategy across web and mobile, build high-performance React and React Native applications, develop shared component libraries and design systems, optimize performance and accessibility, mentor engineers, collaborate with product/design/backend teams, and resolve complex cross-stack issues.

This role involves leading web platform initiatives, mentoring senior engineers, architecting web applications, and implementing technical strategies for improved performance.

The role involves designing and building internal web applications for Nebius, focusing on automating data center operations and developing user interfaces for infrastructure management.

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.

Design, build, and deliver front-end features with strong UX focus. Own technical design, coding, testing, deployment, and monitoring in a continuous delivery, microservices environment. Collaborate with Product, implement automated QA practices, and contribute to production deployments while practicing robust testing methodologies.

Lead front-end technical strategy for Coinbase Advanced trading platform: define and execute a scalable roadmap, deliver a low-latency interface across web and mobile, mentor engineers, anchor complex projects, and ensure high standards for code quality and system design.

Develop and maintain Java backend services for enterprise blockchain applications, integrate APIs with React/Vue frontends, design scalable blockchain solutions, troubleshoot complex backend issues, and collaborate with the team to apply best practices and stay current with blockchain trends.

Design, build, and maintain scalable frontend applications using Vue 3 and TypeScript. Own feature delivery from design through production, build reusable components and architecture, improve performance and accessibility, collaborate with backend teams on APIs, write tests, mentor engineers, and help shape frontend tooling, CI/CD, observability, and security practices.

As a Senior Frontend Engineer at Cinch, you'll lead the modernization and performance optimization of React-based user interfaces, collaborate with cross-functional teams, and architect scalable UI systems with a focus on AI-driven experiences.

The Front End Engineer will lead teams in front-end development, establish coding standards, consult on architecture, and ensure high-quality web applications.

Build high-performance, real-time Angular frontends for AI-driven agent workflows. Implement SSE/WebSocket streaming, advanced state management (Signals/NgRx/Akita), interactive visualizations (Canvas/SVG), HITL components, and performance optimizations. Collaborate with backend and AI engineers on JSON schemas and API contracts. Ensure quality via unit and E2E tests (Cypress).

Own end-to-end frontend development for core crypto payment flows across web and mobile. Improve latency, availability, and SLOs; build user-facing features (contacts, real-time transaction status); identify and fix performance bottlenecks; partner with product/design/backend; mentor junior engineers to reduce customer friction at scale.

The Staff Frontend Engineer will develop shared frontend libraries, enhance performance, and manage a design system to improve user experiences.

Develop and maintain WordPress websites, create custom themes and plugins, ensure cross-browser compatibility, and optimize for SEO. Provide guidance on user experience and explore new technologies.

Design, build, and optimize high-performance TypeScript and React single-page applications, mentor team members, and advocate modern frontend practices while collaborating with cross-functional teams.

Build and maintain React/TypeScript UI components, pages, and data visualizations for a security/compliance platform. Extend component library, optimize performance for large datasets, implement real-time updates, collaborate with designers, backend engineers, and customers to ship high-fidelity, production-ready interfaces.

Own and build frontend experiences across Air's web platform: translate product/design needs into high-quality UI, architect and ship features, improve component design and rendering performance, maintain a scalable design system, enforce accessibility and code quality, mentor engineers, and participate in reviews and hiring.

The Frontend Engineer will build user-facing interfaces for AI software development, utilizing technologies like TypeScript and React, while ensuring code quality and user experience.

We are seeking a Senior Frontend Software Engineer to build advanced web applications using JavaScript and ReactJS, collaborating with a team to enhance user experiences.

Design and implement high-performance Angular frontends for AI-driven interfaces: real-time SSE/WebSocket streaming, complex state with Signals/NgRx, Chain-of-Thought visualizations, human-in-the-loop controls, performance optimization, API schema collaboration, and testing.

Build high-performance, real-time Angular UIs for AI-driven agent workflows. Implement SSE/WebSocket streaming, complex state management (Signals/NgRx), observability dashboards, HITL controls, performance optimizations, and collaborate on API/JSON schema design with backend and AI engineers.

Build and integrate reusable React.js UI components from wireframes, optimize front-end performance and responsiveness, ensure cross-browser compatibility, validate inputs, consume REST APIs, write tests, document code, and collaborate with designers and backend engineers to deliver accessible, secure, and scalable front-end applications.

Build high-performance, real-time Angular frontends for AI-driven agent interfaces. Implement SSE/WebSockets streaming, complex state management with Signals/NgRx, visualizations of agent chain-of-thought, human-in-the-loop controls, performance optimizations, and collaborate with backend/AI engineers on API schemas.

Senior Front End Developer who architects REST APIs (Java/Node.js) and builds Angular-based SPA configurations. Own end-to-end integration and onboarding flows, manage CI/CD with Jenkins and Sonar, implement QA automation, and monitor production with Datadog and Splunk. Lead troubleshooting, test matrices, and release management to ensure production readiness.