Jan
From Czech Republic (GMT+2)
22 years of commercial experience
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Jan – Java, React, Spring
Jan is a Senior Full-stack professional with extensive experience in Java, React, and additionally, Kotlin. His expertise spans diverse domains such as logistics, healthcare, and e-commerce. With 6 years of leadership experience, he has progressed from a developer to a manager and eventually to a director, managing teams across Europe and the US. With Jan's extensive expertise and leadership experience, he will definitely bring immense value to any company.
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Potentially possibleExperience Highlights
Senior Software Engineer (Back-End)
The project involved developing a new microservice-based e-commerce platform for online shops, replacing the legacy system. The platform was initially deployed in Czechia, followed by Austria, with plans for further rollouts across Europe.
- Engaged in architectural decision-making processes;
- Led a code quality and maintainability initiative and was a key member of a task force tackling urgent performance issues before our successful launch in Austria;
- Developed and introduced a "Deploy Buddy" tool, offering a tailored, one-click overview to facilitate safe and reliable deployments across various services and environments;
- Developed new features and tests and fixed bugs;
- Operated in a fully remote environment, with occasional travel to Vienna for collaborative purposes.
Senior Software Engineer (Full-Stack)
The project at DHL IT Services involved developing and maintaining two internal applications: a Java Spring Boot user management application used across various DHL applications, which included implementing new features and fixing bugs, and a predictive analytics software for warehouse operations.
- Initiated the rewrite process from pure JavaScript to TypeScript;
- Executed the complete rewrite, resulting in significant improvements in code maintainability and readability.
Senior Software Engineer (Full-Stack)
The project involved enhancing a Java Spring Boot application for the Collaboration Hub project at a major pharmaceutical company. Its primary focus was on developing new features and resolving bugs. This project played a crucial role in aggregating and presenting "value evidence" documents, supporting value-based healthcare.
- Developed new features and resolved bugs;
- Presented new features to stakeholders.
Performance Engineer Team Lead, Deputy GM, Director of Performance Engineering
A healthcare management application designed to foster managed care techniques that ultimately reduce healthcare costs while maintaining the quality of care.
- Led performance analysis and optimization, mostly focusing on SQL Server internals and Java;
- Achieved successive promotions from a Performance Engineer Team Lead to the esteemed role of Deputy General Manager;
- Managed teams across Prague and Boston, overseeing performance and scalability;
- Initiated and directed the development of an automated performance testing pipeline for REST web services;
- Integrated performance engineering workflow with the company-wide Scrum process;
- Achieved significant performance enhancements, including an 85% increase in supported concurrent users, and maintained 100% SLA compliance for screen response times;
- Optimized release testing report processes, increasing efficiency;
- Directed engineering teams and led recruitment efforts;
- Resolved critical production issues and addressed long-term performance challenges;
- Mentored team members, guiding their professional growth.