Senior Front-end Developer

Madfish; Remote; GBP 50,000 - 80,000; Full time

Job summary

A forward-thinking iGaming firm in the United Kingdom is looking for a Senior Frontend Developer. The ideal candidate will have over 5 years of production frontend experience and 2 years with Next.js. Responsibilities include designing frontend architecture, developing dynamic web applications, and ensuring performance and security standards. This role offers competitive compensation, remote work options, and opportunities for professional growth. Join a team that sets trends in the industry and tackle innovative projects.

Benefits

Remote work, Monday–Friday schedule

Competitive compensation

Opportunities for professional growth

Paid vacation and sick leave

An extra day off

Qualifications

• 5+ years in production frontend, 2+ years with Next.js (App Router).
• Deep knowledge of React and TypeScript.
• Experience with caching strategies and API work.

Responsibilities

• Design frontend architecture and features.
• Develop and maintain Next.js applications.
• Ensure performance, accessibility, and security standards.

Skills

React 19

TypeScript

Next.js

TanStack Query

Tailwind CSS

Git

PWA/Service Workers

Testing (Vitest, Playwright)

Job description

We are an innovative iGaming company that doesn’t just grow but sets trends in the industry! We are currently looking for a Senior Frontend Developer who is ready to build dynamic and innovative web products.

If you enjoy tackling complex tasks, taking on creative challenges, and working in a team that drives the industry forward — let’s build great things together!

Key Responsibilities

• Design of frontend architecture (Feature‑Sliced Design) — layers, modules, boundaries, public APIs of modules
• End‑to‑end feature development: from RFC/ADR → UX/decomposition → implementation → tests → release
• Work with Next.js 15 (App Router, RSC, server/actions, caching, ISR/SSG/SSR, edge/runtime)
• Data management with TanStack Query: caching strategies, invalidation, optimistic updates
• Performance and accessibility: Core Web Vitals, Lighthouse, Web Accessibility (WCAG), code‑splitting, streaming & partial hydration
• PWA: offline scenarios, background sync, push notifications, SW strategies (stale‑while‑revalidate, etc.)
• UI system: design tokens, Tailwind conventions, reusable components, Storybook documentation
• Quality: Vitest coverage, visual snapshots/Storybook‑Vitest, e2e tests with Playwright, testing pyramid
• Observability: Sentry (tracing, release helpers, source maps), Grafana dashboards (FE metrics)
• Security: protection from XSS/CSRF, Content Security Policy, headers, sanitization
• SEO and i18n: metadata, structured data, Next.js sitemap/robots, localization
• Mentorship, code reviews, DX improvements (ESLint/Prettier/biome, commit linters, generators)
• Contribution to processes: ADR, codebase standards, CI/CD gates, release management

Required Qualifications

• 5+ years in production frontend, 2+ years with Next.js (App Router)
• Deep knowledge of React 19 (RSC, concurrent features) and TypeScript (type‑safe APIs, generics, utility types)
• TanStack Query: queryClient, mutations, cacheTime/staleTime, infinite queries, server state
• Tailwind CSS at the design system level (config, presets, apply directive)
• PWA/Service Worker: Workbox/custom SW, offline‑fallback, caching strategies
• Feature‑Sliced Design: correct decomposition by layers (app/processes/pages/widgets/features/entities/shared), public contracts
• Testing: Vitest, storybook‑vitest‑addon, Playwright; ability to build a testing pyramid and speed up runs (watch, sharding)
• Next.js performance: route‑level code splitting, RSC streaming, ISR, dynamic/force‑static rendering, caching headers, image/font optimization
• API work: REST/GraphQL, schemas (OpenAPI/SDL), validation (zod/yup), degradation handling and retries
• Observability: integration with Sentry (frontend+server), Grafana metrics (Prometheus, Loki/Tempo knowledge is a plus), alerting
• CI/CD: builds, linting, test gates, preview environments, release channels (canary/feature flags)

Would Be a Plus

• Backend background (Node.js/Edge Functions), API contract design experience
• Experience with Docker, basic Kubernetes/orchestration knowledge, pm2 (or similar process managers)
• Familiarity with Feature‑Sliced Design (FSD)

What We Offer

• Remote work, Monday–Friday schedule
• Competitive compensation aligned with your experience and skills
• Work on a top‑tier iGaming project
• Opportunities for professional growth and development in a strong team
• Paid vacation, sick leave, and an extra day off