Frontend Engineer | Mid-Senior | React | Trendos

We are building a world-class, AI-driven B2B analytics SaaS. Built from scratch as a core product, it defines a new generation of marketing analytics within Tesonet Group. You’ll join while core architecture, data flows, and engineering principles are actively being designed , with the opportunity to take real ownership and shape how the product is built and how teams collaborate. The platform is built around intelligent automation, real-time data processing, ML modeling, and large-scale distributed systems , with AI deeply embedded at its core. By working with complex data, we deliver a powerful self-service analytics experience that enables faster, smarter marketing decisions. Main Responsibilities Build a framework to support blazing-fast web pages - think sub-second loading times Ensure the codebase is clean and use best practices for your code while the project grows Seek to improve web performance constantly Drive the full lifecycle of new frontend features, from development through code reviews, QA testing, and production deployment Mentor colleagues on web development best practices & provide technical guidance. Core Requirements Proven development experience working with JavaScript and TypeScript Experience with the React framework Deep knowledge of web development, testing, and performance optimization best practices Proven experience in developing high-quality and high-performance front-end web applications that run at scale Team-spirited, proactive, and able to work in a fast-paced environment Fluent in English and Lithuanian, both written and verbal. Tools You’ll Use TypeScript React Docker State management systems Modern bundlers and transpilers. Salary Range Gross salary 4500 - 7000 Eur per month. We are open to discussing a different salary based on your skills, experience, and potential impact. What We Offer Professional growth. Internal and external events, online training, conferences, books - everything you need to reach full potential. Health benefits. Private health insurance, online and on-site workouts, consultations to feel and be your best. Team spirit. Team buildings and parties with games, shows, tastings, food coupons, gifts, and it’s on us. More free time. Stay with us and additional vacation days will be added to your calendar. Additional paid leave. Additional days are covered by us in cases of illness or special occasions. Flexibility. Flexible working time arrangement.