Strong Middle Frontend Developer (вакансія неактивна)

We are looking for a Strong Middle Frontend Developer to join the project full-time. This person will be the primary FE contributor — no splitting between projects. They need to be a thinking partner, not an executor — someone the client’s technical leadership wants to work with directly.

Your responsibilities will include:

• Own any part of the frontend end-to-end — architecture decisions, performance work, integration, testing — without hand-holding.
• Work directly with the client’s technical leadership as a thinking partner.
• Navigate and extend a large, strictly-conventioned, module-based codebase.
• Cover any part of the frontend independently — no “that’s not my area.”
• Use AI-assisted development (Claude Code / Cursor / Copilot or equivalent) fluently and extensively as a primary tool.
  
  

What we expect from you:

Core stack:

• TypeScript (strict) — no-any, no-implicit-any codebase; comfortable with generics, discriminated unions, unknown + narrowing, and yup.InferType-style inference.
• React 19 + Next.js 15 (App Router) — understands the Server Component / Client Component boundary, server-side data fetching in RSCs, layouts vs. pages, route groups, middleware, Server Actions.
• Modern React patterns — custom hooks as the primary unit of logic, controlled state, effects used sparingly and correctly, deliberate memoization; smart/dumb component separation.
• State management — Zustand: store design, selectors, provider-scoped stores, SSR hydration concerns.
• Forms — React Hook Form + Yup: schema-driven validation, server-error mapping back onto fields, controlled/uncontrolled trade-offs.
• Styling — MUI v7 + Emotion: theme-token-driven styling, sx API, no hardcoded values.
• Data layer — Axios: REST integration, interceptors, token refresh / 401 retry flows, typed API clients.
• Testing — Vitest + React Testing Library: meaningful component and hook tests (queries by role/label, not implementation details).

Foundations:

• Performance reasoning — can diagnose re-render storms, understand React’s reconciliation and memoization model, reason about bundle size, code-splitting, SSR/streaming, Core Web Vitals.
• Architecture & data flow — can navigate and extend a large, strictly-conventioned, module-based codebase; respects existing architecture and knows when a pattern should be challenged.
• Auth & app-level concerns — token-based auth, session handling, multi-tenant routing.
• Browser & web fundamentals — solid on HTTP, caching, cookies, the event loop, rendering, accessibility basics.

Tooling:

• AI-assisted development (Claude Code / Cursor / Copilot or equivalent) as a primary tool — non-negotiable.
• Git discipline — conventional commits, granular atomic history, clean PRs.
• ESLint / Prettier / strict CI — comfortable working inside an opinionated, heavily-linted codebase.

Nice to have:

• Mapbox GL or other data-visualization / mapping / charting experience.
• next-intl or other i18n frameworks.
• Sentry or comparable observability / error-monitoring tooling.
• WorkOS / Auth0 / Clerk or similar managed-auth experience.

What We Offer:

• Work at a Top-employer company (according to DOU 2025).
• A strong culture built on empathy, trust, openness, and real care for employees.
• Competitive compensation with regular reviews.
• Paid vacation and sick leave.
• Medical insurance.
• Personal learning budget and access to top HR tools, platforms, and practices.
• Team events and regular team-building activities.
• Flexible hybrid work model with an office in central Kyiv.