React.js Software Engineer - Finland based

We are a technology company that started its journey in 2008. Our main headquarters is located in the picturesque city of Poznań, nestled by the beautiful Malta lake. For more than 17 years, we have been assisting companies in developing and implementing innovative fintech solutions. Leveraging our expertise in areas such as blockchain, online payments, and more, our clients can invent and develop cutting-edge solutions and services that keep them at the forefront of innovation.

React.js Software Engineer

SKILLS: React.js | JavaScript/TypeScript | Redux/Zustand | REST APIs | CI/CD | Testing

B2B COOPERATION: 40-55 €/hour 💰

LOCATION: REMOTE IN FINLAND (occasional travels to Helsinki)

START DATE: ASAP

Key Services and Requirements: A Roadmap to Your Professional Success 🚀

Scope of services (applies to both Mid-Level & Senior):

• Design, build, and maintain high-quality React.js applications within a component-driven architecture

• Architect and enforce component libraries, state management patterns, and frontend standards across teams

• Implement performant, accessible UIs that scale across multiple markets and localization requirements

• Integrate with backend REST APIs and manage async data flows using established patterns

• Ensure code quality, performance, accessibility, and comprehensive testing (unit, integration, end-to-end)

• Collaborate with Product, Backend (Java), Design, Mobile (React Native), and DevOps teams across European markets

• Participate in architectural discussions, technical design reviews, and contribute to platform-wide frontend standards

• Take ownership of the reliability and operability of frontend applications, proactively reducing technical debt

• Leverage AI-native development tools (Copilot, Cursor, Claude) to accelerate delivery and improve code quality

• Support a “you build it, you run it” mindset for reliable delivery and smooth operations

Here’s a set of skills we require:

Middle Level

• 3-5 years of professional software development experience

• Solid experience with React.js (hooks, functional components) and modern JavaScript/TypeScript

• Familiarity with state management (Redux, React Query, Context API, or similar)

• Understanding of RESTful APIs and async data patterns Unit testing with Jest; integration testing is a plus

• Basic knowledge of web accessibility and internationalisation

• Experience collaborating with cross-functional teams and following existing frontend standards

Senior Level

• 6-8 years of professional software development experience

• Deep expertise in React.js (hooks, context, concurrent features) and modern JavaScript/TypeScript

• Strong experience with state management (Redux, Zustand, React Query, or similar)

• Hands-on experience designing and maintaining component libraries and design systems

• Solid understanding of frontend performance optimization (code splitting, lazy loading, bundle analysis)

• Advanced knowledge of web accessibility standards (WCAG 2.1) and internationalisation (i18n)

• Integration and end-to-end testing experience (Cypress, Playwright)

• Experience mentoring mid-level engineers and driving frontend standards across teams

• Familiarity with Docker, CI/CD pipelines (Vite, Webpack, GitHub Actions), and frontend observability (Sentry, metrics, logging)

Nice to have:

• Experience defining and scaling frontend standards across multiple teams or domains

• Practical experience modernizing or refactoring legacy frontend systems

• Active usage of AI-assisted development tools in daily workflow

• Exposure to high-traffic, production-grade applications

• Experience shaping engineering culture and mentoring at scale

• Interest in or experience with React Native