
Staff/Senior Backend Developer at Zelh. Location Information: Ukraine. Zelh is a fast-growing, passionate outsourcing company.. Our mission is to be the most reliable company by offering and maintaining consistently high-quality services.. We achieve the mission by fostering long-term relationships with customers, employees, and vendors. Personal attention, timely communication, and respect for all people are the basis of our business philosophy!. Our client is . a . U.S.-based digital platform that connects individuals with certified mobile mechanics. , enabling users to book diagnostics, maintenance, or repairs directly to their home or workplace.. We are seeking an exceptional backend developer to help establish platform for long-term success. Client uses Convex for backend infrastructure. While prior experience with Convex is not required for this role, having previous experience with . Node.js. is advantageous.. Key Responsibilities:. Lead Stripe-like API-first architecture design, establish standards, and build scalable core business data models. . Resolve critical technical debt, transform service request workflows, and implement robust access patterns. . Design and optimize database schemas for scalability and performance. . Mentor junior engineers, establish best practices, and lead technical discussions.. Ensure system reliability and performance through robust error handling, monitoring, and comprehensive testing.. Qualifications:. 6+ years of backend development with expert TypeScript/JavaScript proficiency. Proven experience with API-first architectures, core business object models, and database schema design.. Deep understanding of authentication, authorization, and role-based access control.. Demonstrated technical leadership, including high-impact decision-making, code review, mentorship, and technical debt reduction.. Working conditions:. Working hours: flexible. Working mode – remote/hybrid. 20 days of PTO, 7 days of National Holidays and 3 sick leaves . English classes . Paid taxi after 10 PM