Top Senior Front End Developer Jobs in Portland, ME

Build and maintain TypeScript/React frontends and SDKs for the Nomina web3 platform, create user-facing dapps, improve developer documentation and DX, and collaborate with product and engineering to deliver high-quality, mobile-friendly features.

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.

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.

Lead frontend architecture and execution for high-traffic Search features using React and TypeScript. Build map-based visualizations, optimize client-side performance and state management, collaborate with product/design/backend, conduct code reviews, mentor peers, and ship production-grade web features.

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.

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.

As a Senior Software Engineer, you will lead frontend development, define architecture, optimize performance, and collaborate across teams to create user-friendly logistics applications.

Build the realtime, HIPAA-compliant messaging and collaboration frontend ('Pulse') that makes an AI colleague feel human. Implement complex interactive data visualizations, micro-interactions, and high-performance accessible interfaces. Work embedded with product and design, own UI quality, iterate on AI-driven specs, and deliver production frontend experiences clinicians will trust.

Develop and maintain scalable, responsive, high-performing web applications using Angular, JavaScript, and TypeScript. Collaborate with product managers, UX designers, backend engineers, and QA teams to deliver quality digital experiences. Integrate REST APIs, implement reusable component and state-management patterns, troubleshoot issues, optimize performance, and support Agile/Scrum development while using monitoring, testing, and source-control tools.

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.

Build and maintain intuitive frontend web applications for data upload, search, visualization, and interactive 2D/3D geospatial tools. Collaborate with scientists to design complex visualizations, modernize the frontend stack, mentor junior developers, and implement automated UI testing and deployment pipelines.

Develop and enhance interactive enterprise planning, reporting, and analytics web applications using SAP Analytics Cloud and front-end web technologies. Build UI/UX components, integrate REST APIs, optimize performance and scalability, review designs, document changes, participate in code reviews, and collaborate with technical teams. The remote role supports a Washington, DC-based federal customer and requires Public Trust clearance and U.S. citizenship.

Design, build, and maintain scalable, responsive web applications using React and TypeScript. Create reusable UI components, implement end-to-end tests with Cypress, optimize performance, collaborate with product/design/backend teams, participate in code reviews, mentor junior engineers, and contribute to architecture and API integrations.

Lead frontend architecture and implementation for new products using React, TypeScript, and Next.js. Collaborate with Product and Design, define patterns and testing strategies, ensure performance, accessibility, and observability, mentor engineers, and drive cross-team initiatives to align frontend systems with backend APIs and platform requirements.

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.

Lead front-end architecture and build high-performance React/TypeScript web applications, integrating with back-end APIs, ensuring type safety, testing, CI/CD, scalability, and UX for AI-driven orchestration workflows.

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.

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.

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.

Own frontend architecture and platform for a unified web console. Build identity-adjacent systems (auth, sessions, CORS/CSRF protections), shared infra and tooling, testing strategies, and enable other teams to ship reliable UIs. Collaborate across design, growth, and infrastructure; participate in on-call rotation.

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.

Lead technical direction and contribute to the frontend codebase, building user-facing tools and mentoring team engineers to enhance 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.

Build and maintain responsive, high-performance user-facing React/Next.js applications for privacy-focused web3 products. Collaborate with backend engineers, identify and fix performance bottlenecks, participate across the product lifecycle, write tested production-quality code, and iterate quickly on UX and developer-facing frameworks.