Senior Full Stack Developer

O projekcie: Join Keepit’s mission to secure the digital world and shape the future of global cloud backup. About the role We are looking for an experienced Full Stack Developer to design, build, and maintain production-grade applications and systems using JavaScript, TypeScript and Node.js. In this role, you will collaborate with cross-functional teams across sales, marketing, and operations to deliver scalable and reliable solutions. A proactive approach, strong collaboration skills, and a commitment to continuous improvement are key to success in this role. About us Our platform provides customers with an immutable, historical archive of their data in systems such as Microsoft 365, Google Workspace, Salesforce, Entra ID, Dynamics 365, and Zendesk. We protect our customers against everything, ranging from ransomware to simple accidents. The majority of our back-end components are written in clean, modern C++ using mainly purpose-built components. Components responsible for business processes and data mining are built using Common Lisp. Everything runs on Linux. We pride ourselves on backing up billions of objects over foreign APIs using imperfect networks on systems with finite memory and making it all happen in a performant, reliable, and predictable way. We offer:   - Umowa o pracę employment contract - 4 additional working days of vacation leave per full calendar year - Health and Life Insurance - 3 days of internal sick leave without a doctor`s note - Employee Capital Plan (PPK) - Multisport card compensation - Full or partial coverage of professional training sessions, meetups, etc - English-speaking club with native speakers - Cosy office in Krakow city centre (Długa, 72) with beverages, fruit, and cookies - Winter and summer parties, events, team-buildings We kindly ask you not to provide us with any sensitive categories of personal data when applying for a job with us. When applying for the vacancy, Keepit will process your personal data, and therefore we recommend that you also read our privacy policy at keepit.com/privacy-policy/, which describes our processing of personal data and your rights as a data subject.   If you notice any misconduct or irregularities that fall within the scope of our whistleblowing procedure, please follow the link keepit.integrityline.com to report them. Wymagania: Required qualifications: - 5+ years of professional experience in full-stack application and system development - Proven track record building and maintaining production-grade applications - Experience working with cross-functional teams including sales, marketing, and operations Core Technologies: - Strong proficiency in JavaScript/TypeScript for both frontend and backend development - Deep understanding of PostgreSQL database design, optimization, and management - Expert-level knowledge of RESTful API design, development, and consumption - Experience with SOAP API integration and XML processing - Proficiency with modern frontend frameworks (React, Vue, or Angular) - Backend development experience with Node.js or similar server-side JavaScript frameworks Integration & Automation: - Hands-on experience with iPaaS platforms: Zapier, Workato, or n8n - Ability to design and implement complex multi-system integrations - Experience building custom connectors and middleware solutions - Understanding of event-driven architectures and webhook implementations