Slawomir Mazur, Java Developer in Wrocław, Poland
Slawomir Mazur

Java Developer in Wrocław, Poland

Member since July 31, 2016
Through his experience as a professional software engineer, Slawomir's evolved his range of skills. Specifically, he excels at detailed-oriented software craftsmanship, understanding people's needs, and delivering robust, high-quality outcomes enabling them to meet their goals. Getting into new domains and exploring new ways of doing things is what he looks forward to in every unique undertaking. Slawomir's can-do attitude is what sets him apart.
Slawomir is now available for hire


  • CodersLab
    Java, JavaEE, JavaScript, jQuery, Spring Framework, JSP
    Java/Kotlin/Groovy, Spring Boot, JavaScript, Node.js, Docker, K8s
  • Picadilla
    Java, Spring



Wrocław, Poland



Preferred Environment

Java, Kotlin, Spring, React, AWS, Docker

The most amazing...

...thing I've accomplished was to finish writing my master thesis.


  • Trainer | Consultant

    2017 - PRESENT
    • Developed with a variety of technologies.
    Technologies: Java, JavaEE, JavaScript, jQuery, Spring Framework, JSP
  • Software Engineer | Independent Technology Consultant | Lecturer

    2015 - PRESENT
    • Worked for a multi-vendor, eCommerce marketplace—integrating a third-party payment gateway in a multi-step onboarding process including data and document verification and migrating from a bespoke gateway-like solution to a Spring Gateway/Feign architecture.
    • Built, for Adamos, an internal marketplace (an IIoT developer center) from the ground up. The app was built with Java 11 with Spring portfolio projects including framework, IO, data, security, and cloud; also deployed Kubernetes to the Azure cloud in a microservice architecture and it had an Angular-based front end.
    • Developed, for Siemens in Hong Kong, a real-time pedestrian and traffic tracing and analysis flow—it controlled traffic at junctions with traffic lights using high-throughput IoT and automotive universal medium radar sensors (UMRR). (Tech stack: Java 11, Keycloak, Hasura, Grafana, Docker, TimescaleDB, AWS ECS, EC2, S3, Route 53.).
    • Worked on an NDA project for a German leader in the field of loans for enterprises. (Tech stack: Java 11, Spring Boot, Cloud, Data, Security, Docker, Kubernetes, Travis CI.).
    • Integrated platforms (FintecSystems, solarisBank) and built the back end and front end architecture supporting iOS and Android clients on an NDA project for a German leader in the field of loan comparison/search—it is essentially a quick cheap online loans & credits for individuals. (Tech stack: Java 8, Spring Boot & Cloud, Docker, Kubernetes, Jenkins, AWS ECS, EC2, S3, and Route 53.).
    • Worked on an NDA project for a German leader in digital lean management. (Tech stack: ES6, Sails, Node.js.).
    • Integrated, for Onfido, the API of a world-leading identity verification solution with third-party fraud prevention and identity services vendor build. (Tech stack: Java 11, Spring Boot, Docker, and Kubernetes.).
    • Integrated, for CRM suite, dealer management systems for efficient and effective communication, combining social media activities with AI. (Tech stack: Java 8, JAX-WS, JAX-RS, JAXB, and SOAP.).
    • Collected, processed, and analyzed real-time, streaming data from IoT network of over 5 million devices for ISTA. (Tech stack: Java 8, JAX-WS, JAXB, and SOAP.).
    • Determined all aspects of development from the applicable technology stack and workflow to coding standards and choosing the system architecture and each individual component and connections between the components of this system.
    • Designed the entire system based on the received requirements adhering client unified development standards.
    • Worked closely with the client, product manager, and developers in order to envision, model, and lay the foundation for the project.
    • Implemented quality assurance by successfully adapting TDD discipline to daily routines.
    Technologies: Java/Kotlin/Groovy, Spring Boot, JavaScript, Node.js, Docker, K8s
  • Tech Lead | Senior Java Developer

    2016 - 2017
    • Orchestrated technology and team members.
    • Introduced TDD.
    • Introduced clean code and guided workshops on the subject.
    Technologies: Java, Spring
  • Senior Java Developer

    2014 - 2016
    • Upgraded to Java version 8.
    • Improved the back-end system performance by a meaningful factor.
    • Made extensive use of Amazon Web Services to compile, package, and deliver our software.
    Technologies: Java, Spring
  • Software Engineer

    2013 - 2014
    • Involved in the architecture, development, and maintenance of high performance, distributed, transactional, and scalable security system which processes billions of security events per day.
    • Guided back-end guild workshops on cutting-edge software solutions.
    • Introduced a number of open-source solutions to common project problems.
    Technologies: Java, Spring
  • Software Engineer

    2011 - 2012
    University of Heidelberg
    • Deployed an open-source, data-mining platform, and KNIME—for integrating, sharing and processing HCS data using a work-flow-oriented architecture.
    • Developed image processing (signal processing, automated segmentation, morphological operation, structure identification, filtering, classification), statistics, bioinformatics, and analysis methods.
    • Implemented data analysis including data modeling and visualization.
    Technologies: Java, ImageJ, KNIME
  • Associate Software Engineer

    2010 - 2012
    ETH Zurich
    • Involved in designing and modeling data from life science—essentially large scale biological image and sequence data.
    • Worked at a university that was ranked #11 in the world's ranking ETH scores in computer science and #18 overall according to US News Education.
    • Wrote three publications on the subject.
    Technologies: Java, ImageJ, KNIME
  • Senior Developer

    2009 - 2011
    Softisland Sp. z o.o.
    • Introduced the PHP Zend Framework to the company as an optimal web application development platform and Magento as the best eCommerce solution.
    • Led the development of a large-scale Magento solution that fits client's needs.
    • Developed a large amount of commercial and open extensions for Magento.
    Technologies: PHP, Zend Framework, Magento
  • PHP Programmer

    2008 - 2009
    Planet Soft IT Outsourcing
    • Worked side by side as a PHP programmer—building various social networking services and websites.
    • Developed mostly with the Zend Framework and Symfony.
    • Designed, developed, tested, and documented web applications.
    Technologies: PHP, Zend Framework


  • Professional Development and Training (Other amazing things)

    • Magento Certified Front-end Developer
    • Magento Certified Developer Plus
    License: 5359963

    • Oracle Certified Expert, Java Persistence API Developer
    • Oracle Certified Professional, Java Programmer
    License: OC1104347

    • Zend PHP 5.3 Certified Engineer
    • Zend Framework Certified Engineer
    • Zend Certified Engineer
    License ZEND011643

  • (Development)

    I built a Magento 2-backed shopping platform for the eBay giant, focuses on companies in the automotive industry and offers workshop and paint shop supplies, car care, and cleaning products for detailing and accessories.

  • UrbanCity (Development)

    A Magento shop for Polish clothing retailer in Germany.

  • Gavle GmbH (Development)

    A shopping platform which I built together with over a dozen of extensions.

  • Sudoku Puzzle (Development)

    Sudoku is a logic-based, combinatorial, number-placement puzzle. The objective is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 sub-grids that compose the grid (also called "boxes," "blocks," "regions," or "sub-squares") contains all of the digits from 1 to 9.

    This a version of Sudoku that I built.


  • Languages

    Java, Kotlin, JavaScript, Go
  • Frameworks

    JPA, Hibernate, Spring MVC, Spring Security, Spring Boot, Express.js
  • Libraries/APIs

    Node.js, React
  • Tools

    Git, Jenkins, GitLab, GitHub
  • Paradigms

    Test-driven Development (TDD)
  • Platforms

    JEE, Magento, Linux, Android, Docker, Kubernetes
  • Storage

    MySQL, Spring Data, MongoDB, PostgreSQL, Couchbase
  • Other

    OCJP6, Software Development, Software Engineering, AWS


  • Master of Science degree in Computer Science
    2008 - 2010
    Wroclaw University of Technology - Wrocław, Poland
  • Bachelor of Science degree in Computer Science
    2004 - 2008
    The State Higher Vocational School in Nysa - Nysa, Poland


  • Magento Certified Front End Developer
    Magento Commerce
  • Magento Certified Developer Plus
    Magento Commerce
  • Oracle Certified Expert, Java Persistence API Developer
    JULY 2014 - PRESENT
  • Oracle Certified Professional, Java Programmer
    APRIL 2012 - PRESENT
  • Zend PHP 5.3 Certified Engineer
    Zend Technologies
  • Zend Framework Certified Engineer
    Zend Technologies
  • Zend Certified Engineer
    Zend Technologies

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