Lead React Developer, Tietoevry Create (m/f/d)

About the company MentorMate creates durable technical solutions that deliver digital transformation at scale by blending strategic insights and thoughtful design with brilliant engineering. With mature and established practices in enterprise web and mobile development, quality engineering, technical architecture, human-centered design, cloud, DevOps, data, and analytics, the company provides challenging careers in a friendly and global people-oriented environment. We value every team member and share our success through flexible working models, competitive pay and benefits, and advancement opportunities. As part of global technology company Tieto Tech Consulting, MentorMate enables people to work on impactful, global projects for recognizable brands and grow their careers in a team of over 10,000 experts. About the role We are seeking a highly skilled Lead React Engineer to join our team. The ideal candidate will have deep experience in mobile development, particularly with React, and a strong ability to troubleshoot and resolve complex issues, especially those involving third-party libraries and native integrations. This role requires excellent communication skills, a proactive mindset, and the ability to support and mentor less experienced engineers. Responsibilities Develop, maintain, and optimize mobile applications using React and React Native. Collaborate closely with backend, product, and design teams to create well-integrated features. Provide architectural guidance and technical leadership, establishing clean boundaries, modularization, and scalable feature structures. Break down complex projects into simple, step-by-step plans. Support teammates by reviewing code, sharing knowledge, and helping unblock technical issues. Work across mobile and web when needed, contributing to overall platform quality. Participate actively in continuous improvement across tooling, testing, and development practices. Requirements 5+ years of experience in both mobile and web development, with a strong focus on React. Proven ability to identify, debug, and resolve complex issues quickly and effectively. Experience with Typescript, React Navigation, native modules (iOS/Android). Experience with test tools: Jest , Vitest , RTL/RNTL . Able to mock complex integrations and know when to use unit vs integration tests. Ability to structure features cleanly, modularize, and keep architecture simple and scalable. Ability to read and modify native mobile code (iOS and Android). Strong communication skills and a proactive approach to problem-solving. Understands PHI/PII sensitivity and best practices for secure data handling. Able to own a technical domain (mobile or web) end-to-end. Experience working in structured codebases with complex architectural decisions. Excellent verbal and written English communication skills. Preferred Qualifications Experience with state management, forms & validation. Experience with SDKs like Segment, Datadog, FullStory, Firebase, Notifee. Exposure to chat/video SDKs (CometChat, OpenTok). Ability to troubleshoot iOS/Android build issues. Experience with auth systems like Cognito/Amplify or OAuth/OIDC. Familiarity with Agile methodologies and best practices. Comfortable integrating with backend teams and CRM tools like Salesforce. Experience with Browserstack or similar. Able to collaborate using Figma and design tokens. Experience implementing or extending design systems. Care for accessibility, responsiveness, and polished UX. Knowledge of DevOps practices and CI/CD pipelines. Experience working in cross-functional teams with varying levels of technical expertise. Benefits Professional Growth: Clear career path with opportunities for vertical and horizontal advancement Regular Salary Raises: Based on career path and performance Social Security (IPS): Access to medical coverage and retirement benefits Aguinaldo: Legally mandated benefit Flexible Work Environment: Option to work remotely, in-office, or a combination of both Upskilling: Access to various trainings, knowledge-sharing events, and personal learning budget Referral Program: Bonus for referring employees Teambuilding: Enjoy team gatherings and communities of interest #LI-DNI At Tietoevry, we believe in the power of diversity, equity, and inclusion. We encourage applicants of all backgrounds, genders (m/f/d), and walks of life to join our team, as we believe that this fosters an inspiring workplace and fuels innovation. Our commitment to openness, trust, and diversity is at the heart of our mission to create digital futures that benefit businesses, societies, and humanity. Diversity, equity and inclusion (tietoevry.com)