Come Back Agency is a rapidly growing company in the digital field, specializing in developing brands, creating web projects, and designing mobile applications. We are looking for a skilled and motivated Frontend Engineer (Next.js) to join our international team.

US schedule. Working hours from 04:00 pm to 00:00 am EET;

Must-Have Qualifications

• 2+ years professional experience with Next.js and TypeScript.
• Rendering & data fetching: SSR, SSG/ISR, routing (App Router), server/client components, API routes.
• Secure auth on the client: JWT, jwt-decode, refresh-token flows, RBAC/permissions, route guards/middleware.
• Building and consuming REST APIs; strong HTTP/HTTPS fundamentals (status codes, caching headers, ETags).
• Real-time UX with WebSockets (live updates, presence, optimistic UI).
• Complex UI:
  • Tables (sorting, filtering, pagination, virtualization).
  • Drag & Drop (dnd-kit or similar).
  • Multi-step forms (wizard state, validation, optimistic/resume).
  • Kanban views and chat integrations.
• State management: Zustand and/or Redux (Toolkit), selectors, normalized state.
• Zod for runtime validation (forms, API responses, schemas shared across client/server).
• Sass/SCSS and component libraries; responsive & accessible (a11y) UIs.
• Charts/visualizations (time-series, aggregates; preparing API data for charts).
• Working with files & videos (upload, preview, player integrations, basic optimization).
• Google APIs on the client, including Calendar (OAuth, scopes, token refresh).
• Performance & reliability: optimization, caching strategies (HTTP cache, SWR/React Query patterns), code-splitting, lazy loading, lighthouse metrics.
• Next.js middleware for security, auth, and edge logic.
• Solid OOP/SOLID understanding applied to frontend architecture.
  

Nice-to-Have

• 3D model libraries (e.g., three.js, react-three-fiber; loaders, GLTF/DRACO, scene graph basics).
• Upwork integration (widgets, embeds, or API).
• Testing: Jest, React Testing Library, Playwright/Cypress.
• Observability: error tracking & analytics (Sentry, GA4), feature flags (LaunchDarkly).
• Realtime beyond websockets (SSE/WebRTC), offline-first (service workers).
  

Responsibilities

• Ship high-quality Next.js features using SSR/SSG/ISR appropriately; design data-fetching that balances TTFB, cacheability, and freshness.
• Implement secure client auth (JWT/jwt-decode, refresh flow) with RBAC and route/middleware guards.
• Build complex product UIs: tables, DnD, multi-step forms, kanban boards, chat, real-time dashboards/charts.
• Integrate Google Calendar and other Google APIs; handle token lifecycles safely.
• Handle files/videos (uploads, previews, players) and transform API data into chart-ready datasets.
• Contribute to and evolve a custom UI kit/design system (tokens, components, theming, docs).
• Drive performance, accessibility, and maintainability with tests, linting, and CI.
  

Architecture for Large Projects (What We Expect You to Practice)

• Feature-oriented/Feature-Sliced or Clean Architecture structure: clear boundaries (entities, features, pages, shared), anti-coupling, and predictable imports.
• Module encapsulation: local state co-located with features, public API per module (index exports), minimal cross-feature leakage.
• Shared contracts: Zod schemas/types shared across server & client to keep validation and types in sync.
• Scalable state strategy: combine server data (SWR/React Query or RSC) with client state (Zustand/Redux); avoid global state by default.
• Performance as design: route-level code-splitting, dynamic imports, memoization, virtualization, image optimization, and careful third-party usage.
• Caching strategy: leverage Next.js caching (fetch cache, revalidate, route segment config), HTTP cache headers, CDN behavior; know when to opt out.
• Security & middleware: edge-side checks, auth headers, CSRF/XSS mitigation, input/output validation via zod.
• Observability & DX: consistent logging, error boundaries, analytics hooks; ESLint/Prettier rules, storybook/docs for the UI kit.

We Offer:

• Fixed salary in USD;
• Flexible work schedule;
• Professional growth and support from experienced colleagues;
• Supportive leadership with minimal bureaucracy;
• English language lessons to boost your communication skills.