Join our innovative tech team as a Senior Frontend Developer and play a pivotal role in elevating our product's user experience and driving business growth. We offer flexible work arrangements, allowing you to work fully remotely or from our offices in Warsaw or Kyiv. About Our Company: We are a pioneering mobile and web application ( ohayu.com ) that simplifies international mobile data package purchases, leveraging cutting-edge eSIM technology. Our product enables seamless internet access while traveling, offering rates significantly lower than roaming and eliminating the need for local operators or physical SIM cards. Key Responsibilities: Own and optimize the frontend architecture, ensuring scalability and high performance. Collaborate with our design team to translate Figma designs into responsive, high-quality user interfaces. Enhance website performance, speed, and accessibility across devices and browsers. Implement rapid, iterative changes to support A/B testing and continuous UX improvement. Mentor and support junior frontend developers, conducting code reviews and sharing expertise. Requirements: 7+ years of experience with JavaScript. 5+ years of experience with React. 4+ years of experience with Next.js. 3+ years of experience with TypeScript. Strong proficiency with the Vite ecosystem and modern build tools. Excellent knowledge of Crash Analysis Tools and Production Management. Independence, full ownership of tasks, and strong mentoring and brainstorming skills. At least intermediate English level (all work communication is in English). Nice to Have: Familiarity with styled-components or other CSS-in-JS libraries. Why Join Us: Be part of a product-driven application with a strong emphasis on UX/UI, where your ideas are valued and you have the freedom to innovate. Experience a startup environment with a groundbreaking venture in the rapidly evolving field of eSIM technology, shaping the future of connectivity and mobile devices. Enjoy the opportunity to work on a project that is revolutionizing the way people stay connected while traveling. Join our team in reshaping the future of connectivity and apply now to take your career to the next level. Apply for this job