Senior Frontend Engineer

Xsolla is looking for a Senior Frontend Engineer with 6+ years of experience for remote full-time work on identity and wallet infrastructure.

Responsibilities: - Own the frontend of your product area end-to-end: from task definition with product managers and designers to implementation, release, and monitoring in production. - Own technical decisions for this frontend, documenting rationale. - Own the architecture of frontend applications and the shared UI library/SDK used by other teams. - Ensure measurable frontend quality: performance, reliability, and security of user scenarios. - Design and develop user scenarios: login, account management, wallet onboarding, and transaction signing. - Monitor these scenarios in production (errors, performance, drop-offs) and act on results. - Make and document architectural decisions for frontend applications. - Develop the shared component library and frontend SDK used by other Xsolla teams. - Align API contracts with backend engineers, including error handling, retries, and edge cases. - Own performance budgets: Core Web Vitals and bundle size. - Improve the engineering environment: build, linters, tests, CI. - Conduct code reviews. - Set up and maintain AI tools in repositories (Claude Code, Codex, Cursor: rules, context, harness) so the team uses them effectively.

Requirements: - 5+ years of commercial frontend development. - TypeScript in strict mode: generics, utility types, discriminated unions, typing module boundaries and external data. - Platform-level JavaScript: event loop, async, closures, memory management; able to find memory leaks and explain causes. - Deep experience with React: rendering model, profiling, eliminating unnecessary re-renders. - Understanding of server, global, and local state separation and tool selection; knowledge when SSR is justified. - Semantic, responsive, cross-browser markup; modern CSS (CSS Modules, CSS-in-JS). - Accessibility: ARIA, keyboard navigation, screen reader support. - Performance analysis: profiling, bundle analysis, Core Web Vitals. - REST API integration: error handling, retries, request cancellation, contract alignment with backend. - Web security basics: XSS, CSRF, CSP, secure token handling, sessions, user data. - Testing at the right level: unit, integration, E2E. - Git, CI, Docker, linters and formatters. - Daily practical use of AI tools for development and review (Claude Code, Codex, Cursor), including setup for repository. - Ability to read technical documentation in English. Nice to have: - Experience in domains with high security requirements: authentication and identity (OAuth2/OIDC flows on frontend), payments, crypto wallets. - Web3 frontend: wallet integration (embedded and browser), EIP-1193, EIP-6963, EIP-712; viem, wagmi, ethers.js. - Next.js or Nuxt, SSR in production. - Design systems and component API design, UI kits. - Hybrid applications: WebView, React Native.

Full-time employment, schedule 5/2, remote work.