Top Front End Developer Jobs in Belfast

Full-Stack Engineer responsible for developing and maintaining front-end and back-end components, collaborating on product solutions, and improving user interfaces.

The Frontend Engineer will implement UI features, automate UI testing, and oversee production releases while focusing on user experience in the blockchain space.

Design and implement developer-facing UI from Figma to production using Hotwire (Turbo + Stimulus) and ViewComponents. Own the dashboard, API playgrounds, docs, marketing site, and data visualization. Optimize performance and bundle size, maintain a coherent component system, and ship polished, production-ready front-end with tests and CI/CD.

As a Senior Frontend Engineer, you'll deliver web-based AI modeling tools, optimize frontend architecture, and collaborate on complex UI components.

As a Senior Frontend Engineer, you'll design and deliver React/TypeScript components, optimize performance, and lead frontend architecture for complex web apps.

As a Senior Frontend Engineer, you'll create production-ready web components using React and TypeScript, optimize performance, and collaborate with teams to deliver complex UIs for AI applications.

As a Senior Frontend Engineer, you'll lead the development of web apps using React and TypeScript, creating intuitive, data-driven UIs, while implementing best practices and performance optimization.

Own end-to-end features across Java backends and a TypeScript/Angular frontend for a multi-tenant SaaS platform. Design APIs, schema and queries (MySQL/ClickHouse), build performant UIs, write unit/integration/e2e tests, deploy via containers/CI-CD, and integrate LLM/agentic workflows to help users find and fix data quality issues.

Lead frontend work on a TypeScript/Angular product, owning component architecture, state management, performance, and tests. Build data-dense UIs and Storybook-driven components, ship agentic (LLM) features, shape APIs and implement backend Java endpoints, write SQL, mentor engineers, and work directly with product, design, and customers to deliver end-to-end features.

Lead front-end technical strategy across multiple teams for a complex, data-dense merchant platform. Own architecture, component systems, state management, performance, accessibility, and front-end observability. Mentor engineers, drive cross-team alignment, and partner with Product, Design, and backend engineers to deliver a cohesive merchant experience including the Primer AI Companion.

Lead the design and implementation of core authentication infrastructure at Phantom, focusing on secure authentication systems, secrets management, and API integrations.

Build and ship frontend features end-to-end for Supabase Studio and marketing/docs sites. Launch 0→1 products, iterate from user feedback, and own quality pipelines (types, tests, CI, accessibility, visual/regression, bundle budgets). Work across the stack publicly, tighten tooling for AI agents, add automated checks to prevent regressions, and operate autonomously in an async, remote environment.

Lead front-end engineer on the Mapper Team building scalable data-visualization and real-time multi-user front-end features. Own end-to-end projects, contribute to architecture and processes, mentor peers, participate in hiring, and deliver high-performance, testable, maintainable UI code.

The role involves developing high-quality Vue.js applications, creating interactions, collaborating with back-end engineers, and writing tests.

Owner of the asset discovery experience across tokens, perpetuals, and prediction markets. Design, build, and scale features for web, mobile, and browser extension platforms. Lead initiatives to add blockchain support and new products, interface with users and developers for feedback, and help grow and hire a high-performing Discovery team.