Top Front End Developer Jobs in Hartford, CT

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.

Lead architecture and delivery of large-scale React and React Native frontends. Define frontend strategy and best practices, build shared component libraries and design systems, optimize performance and accessibility, collaborate with product/design/backend teams, mentor junior engineers, and resolve complex frontend and cross-stack issues.

Build and ship polished, accessible, high-performance front-end features for Deepgram's Console and Playground. Partner with product and design to translate ideas into incremental releases, improve internal tools, and uphold front-end engineering standards through code reviews and design discussions.

Build and own end-to-end full-stack systems for AI-powered agentic trading across web and React Native mobile. Implement real-time, low-latency UIs and Go backend services, integrate streaming AI/ML features and market data, drive architecture and code quality, and collaborate with AI/ML, design, and product teams to ship production-ready features used by millions.

Lead frontend-leaning full-stack implementation work for carrier and enterprise integrations: architect reusable UI and API layers, author RFCs, guide technical delivery, enforce testing and security best practices, and partner with cross-functional teams to scope and ship production integrations.

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

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.

Support development and maintenance of responsive web applications using JavaScript, HTML5, and CSS3. Build user-friendly interfaces, debug cross-browser issues, follow coding standards, participate in code reviews, and collaborate with designers and senior developers. Assist with website maintenance and testing.

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.

Build and own end-to-end frontend experiences for Coinbase card products across web and mobile. Ship high-scale consumer features, improve payment flow performance and SLOs, reduce latency and CX contacts, mentor engineers, and collaborate with product, design, and backend teams to deliver reliable, user-focused card functionality.

Build and own complex frontend features using Vue 3 and TypeScript while developing the Python services and APIs that power them. Improve performance, accessibility, testing, CI/CD, and observability; collaborate with product and design; mentor engineers and apply AI-assisted development tools responsibly to accelerate productivity and maintain quality and security.

Build and ship performant, polished frontend features using React/TypeScript. Refactor code incrementally, implement smooth animations, contribute to backend Node.js APIs when needed, use AI-assisted tools, own production deployments, and collaborate directly with CTO/CPO on product and design.

Build user-facing features with React and TypeScript, implement responsive UIs from Figma, collaborate with design, deploy via continuous deployment, learn Node.js/backend, use AI coding tools, and ship production-ready features while receiving mentorship.

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.

Develop modern web applications focusing on UI components using React while ensuring performance, accessibility, and cross-browser compatibility.

3-month contract Frontend Engineer to build client-facing UIs and integrations for cybersecurity use cases. Collaborate with product, design, and engineering to deliver secure, performant, scalable features, maintain component libraries and automated tests. Remote (GMT+8) role focused on TypeScript and modern web tooling.

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.

Develop secure, data-rich frontend features using React and TypeScript for a DoD mission-planning platform. Integrate UIs with backend APIs, support map-based and AI-enabled decision-support workflows, write unit/integration tests, participate in code reviews and security remediation, and collaborate with cross-functional teams with periodic onsite sprint planning in Laurel, MD.

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.

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.

Build and optimize customer-facing features with a frontend focus, owning end-to-end delivery. Work across the stack to implement APIs and data flows, improve performance and accessibility, debug production issues, and collaborate with product and design to ship high-quality, tested interfaces.

Lead ownership of core feature-flag surfaces to ensure consistent, high-quality UX across teams. Set priorities from customer evidence, drive design-system adoption, prototype hybrid human-agent workflows, improve frontend performance at scale, and build shared interaction primitives (tables, filtering, sorting, bulk changes). Influence cross-team implementation, migrate call sites to shared foundations, and translate platform/library capabilities into product improvements.

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.

Build and maintain responsive, high-performance web applications using React. Collaborate with designers, backend engineers, and product managers to integrate REST/GraphQL APIs, optimize performance and accessibility, write reusable code, participate in code reviews, and improve frontend architecture and development standards.