Mid/Senior React Developer (hybrid from Warsaw)

We are seeking a skilled Mid/Senior React Developer to join our team. 

Responsibilities

• Feature Delivery & Code Quality 

  Own end-to-end delivery of frontend features from UI/UX implementation to complex business logic.

  Write production-grade TypeScript with strict type safety and comprehensive test coverage Participate in code reviews with a focus on maintainability, performance, security, and accessibility.

• Unified Codebase Contribution 

  Develop shared components, hooks, and utilities that work across Web and Mobile platforms Ensure code reusability through proper abstraction and monorepo discipline 

  Collaborate with architects to identify opportunities for cross-platform unification 

  Document patterns and decisions for team knowledge sharing 

• AI-Augmented Development 

  Leverage AI-powered workflows to accelerate repetitive tasks: refactoring, test generation, code profiling 

  Use agents for code review assistance, documentation generation, and debugging 

  Continuously optimize your development velocity through appropriate AI tooling 

  Share effective workflows with the team to elevate collective productivity 

•  Performance Ownership 

  Treat performance as an architectural constraint, not a post-hoc optimization 

  Monitor and improve Core Web Vitals (LCP, INP, CLS) for web applications 

Qualifications

• React Production Experience 

  Deep understanding of React lifecycle, hooks patterns, and performance optimization.

  Experience with strict TypeScript in real codebases.

• AI Augmentation Proficiency 

  Demonstrated experience using AI agents to enhance development workflow.

  Ability to articulate specific examples of how you've used AI tools to improve productivity Understanding of when AI assistance adds value and when manual approaches are more appropriate.

  Familiarity with agent orchestration concepts beyond basic autocomplete.

• Monorepo & Unified Codebase Mindset 

  Experience with Turborepo, Nx, or similar tools. 

  Understanding of shared logic, types, and component patterns across platforms.

• Testing Discipline 

  Unit and integration testing with Vitest or Jest.

  React Testing Library proficiency. 

  Commitment to maintaining test coverage on critical paths.

• Performance Engineering Mindset 

  Understanding of Core Web Vitals (LCP, INP, CLS) and their optimization strategies. 

  Ability to articulate the business impact of performance.

  Experience with performance budgets, profiling tools, and optimization techniques. 

  For candidates declaring React Native experience: awareness of bridge overhead, list virtualization, and memory management.

• Security Awareness 

  Understanding of OWASP Top 10 and common frontend security vulnerabilities. 

  Secure coding practices for authentication, authorization, and data handling. 

  Awareness of dependency security and supply chain risks.

• Language Skills & others

  English B2+ (mandatory) for technical documentation and cross-team collaboration. 

  Readiness to work from our Warsaw office at least 1 day per week.

Benefits

• Unique TEAL culture, relationship- and respect-driven community, non-corporate atmosphere.

• Agile approach and no bureaucracy.

• Outstanding integration trips to various places in Europe for all employees.

• Activities to support your well-being and health.

• Luxmed Gold Extended medical care and Multisport Plus benefit.

• Engagement in innovative projects within a supportive and collaborative environment.

• Flexible working arrangements to promote work-life balance.

• Access to modern tools and technologies to enhance productivity.