Tech Lead Full Stack Developer (f/m/x)

Wymagania: - At least 8 years of software engineering experience, including 3+ years in full‑stack roles designing, building, and launching web platforms - Strong expertise in modern frontend frameworks (React, Angular, or Vue), including component‑driven architecture, state management, routing, and responsive UI - Solid backend experience covering RESTful APIs, microservices, domain‑driven design, scalable architectures, and fault tolerance - Proven ability to build platforms and tools from scratch and deliver end‑to‑end solutions under tight timelines - High level of autonomy: ownership of technical decisions, task management, and delivery with minimal supervision - Experience with relational (PostgreSQL, MySQL) and NoSQL (MongoDB, Cassandra) databases - Proficient with Git and version control workflows - Deep understanding of architectural best practices combined with a fast‑paced, pragmatic, and results‑driven delivery mindset - Availability to work from the Kraków office 6–8 times per month - Residing in Poland required O firmie: - Sii is the leading technology consulting, digital transformation, engineering, and business services vendor in Poland. We already employ more than 7 300 professionals and implement projects in a variety of industries for clients from many countries around the world. The Great Place to Work title, won 10 times in a row, proves that at Sii, we create a friendly work environment. - Sii ensures that all employment-related decisions are made solely on the basis of qualifications and competencies. We are committed to equal treatment of all individuals, regardless of any protected characteristics, and promoting a diverse and inclusive work environment. Zakres obowiązków: - Architect, design, and build a scalable web platform from scratch, covering both frontend and backend - Lead development of user‑facing features using modern frontend frameworks - Develop and maintain backend services, including APIs, microservices, data models, and business logic - Design resilient, performant architecture across databases, services, and APIs - Collaborate closely with product, business, and engineering stakeholders in an Agile (Scrum) environment - Ensure high‑quality, rapid delivery through CI/CD pipelines, automated testing, and code reviews - Design and build scalable cloud infrastructure, preferably on GCP, using infrastructure as code, containerization, and serverless solutions - Mentor engineers, promote team autonomy, uphold architectural standards, and drive technical excellence - Work with both relational and NoSQL databases Oferujemy: - Great Place to Work since 2015 - it’s thanks to feedback from our workers that we get this special title and constantly implement new ideas - Employment stability - revenue of PLN 2.1BN, no debts, since 2006 on the market - We share the profit with Workers - over PLN 76M has already been allocated for this aim since 2022 - Attractive benefits package - private healthcare, benefits cafeteria platform, car discounts and more - Comfortable workplace – class A offices or remote work - Dozens of fascinating projects for prestigious brands from all over the world – you can change them thanks to Job Changer application - PLN 1 000 000 per year for your ideas - with this amount, we support the passions and voluntary actions of our workers - Investment in your growth – meetups, webinars, training platform and technology blog – you choose - Fantastic atmosphere created by all Sii Power People