Senior Back-end Developer2019 - 2021OUTFRONT Media (via Toptal)
Technologies: Kubernetes, Java, Dropwizard, Scala, Datadog, Microservices, AWS
- Worked on a sophisticated system for scheduling advertising campaigns on LED displays in trains and subways of New York and Boston.
- Oversaw the transition of the project to live and the ongoing production monitoring and support.
- Created an external-facing API in Java and Scala to enable scheduling of advertising campaigns and their further inspection.
- Wrote automated tests on the unit level and on the environments.
- Managed the Kubernetes configuration and Helm charts for the deployed services.
- Integrated a legacy campaign scheduling system.
Senior Java Developer2018 - 2019Nordea | LTI
Technologies: Spring, Gang of Four (GOF) Design Patterns, Java 8, AssertJ, Agile, JUnit, Continuous Delivery (CD), Test-driven Development (TDD), Scrum, DevOps, Microservices, REST, Angular, Spring Boot
- Worked on a large tool that manages deployments and configurations of almost all the software in the organization.
- Transitioned a large monolithic application into a microservice architecture.
- Implemented brand new microservices with a Java Spring Boot back end that nonlinearly corresponds to functionalities in the previous generation application.
- Implemented a UI based on Angular 6 with dynamic features following MVVM patterns.
- Created and maintained a continuous delivery pipeline that runs automated deployments and testing procedures on environments.
- Participated in the architectural design of new components being developed.
- Followed a Scrum-based development process and worked towards sharing the experience to make the process smooth and genuinely agile.
- Implemented a caching approach for various types of platform data using the Caffeine library and Spring Boot.
Senior Java Developer2017 - 2018DWP UK
Technologies: Gang of Four (GOF) Design Patterns, Java 8, AssertJ, Agile, JUnit, Jira, Grafana, Splunk, Pair Programming, Kanban, Test-driven Development (TDD), Apache Kafka, Dropwizard, MongoDB, REST
- Participated in digitalization of complex social benefits system business processes for social care agents and claimants in the UK used by millions of people across the country.
- Planned and designed the solutions that support and automate various processes (from payments to housing verification and so on), involving input from user research and UI design.
- Implemented a REST web service's back end and front end for the platform.
- Utilized TDD, strong coding practices, pair programming, and other Agile principles to implement new features and refactor legacy code.
- Maintained and gathered statistics for the working production system (Splunk, Grafana).
- Solved issues and bugs concerning the running production system.
- Participated in Kanban whiteboard-based development with a close relationship between development and QA.
- Implemented highly available third-party-system communication with Kafka queues.
Senior Java Developer2016 - 2017HMRC
Technologies: Gang of Four (GOF) Design Patterns, Java 8, AssertJ, Agile, JUnit, Domain-driven Development, Grafana, Kibana, Continuous Delivery (CD), Continuous Integration (CI), Kanban, Reactive Programming, Test-driven Development (TDD), Docker, MongoDB, REST, Play, Scala
- Designed, implemented, and supported crucial government platform components used directly by millions of tax payers.
- Created reactive REST services used for customer messaging, profile management, and authorization.
- Contributed to the release management for microservices deployed on a custom-built, Docker-based platform.
- Used a fully Agile development process which included Kanban, robust tesing/quality assurance procedures, and heavy use of pair programming.
- Maintained, monitored, and analyzed usage patterns on running production systems with Kibana and Grafana.
Senior Java Developer2014 - 2016Sky
Technologies: Amazon Web Services (AWS), Gang of Four (GOF) Design Patterns, Java 8, AssertJ, Agile, JUnit, Domain-driven Development, Test-driven Development (TDD), Kibana, Grafana, AWS ELB, AWS, Ansible, Docker, Angular, Apache Kafka, Cassandra, REST, Dropwizard, Java
- Re-implemented crucial components of monolithic video player back-end application in a new REST microservice architecture from the very beginning of the project to production release and later support.
- Contributed to all levels of software development (planning, development, functional testing, NFT testing, deployment, infrastructure configuration, maintenance).
- Worked in a very Agile development environment (constant pair programming, strong TDD, extreme emphasis on quality assurance and testing, and full Scrum which later turned to Kanban).
- Designed, implemented, and constantly improved continuous delivery pipeline including fully seamless deployment scripts that could deploy do production without any disruption.
- Provided real-time monitoring, maintenance, and on-call support of a heavily used (up to 2,000 TPS, 10 million user base) video application's back end.
- Prepared demo applications (Angular front end) and showcases for other teams and non-technical business representatives.
- Designed and implemented custom Angular-based application which was fine-tuned for monitoring running the back end on all environments.
- Implemented caching in Dropwizard for the VOD content and streaming data with the Ehcache library.
Senior Java Develper2013 - 2014Gamesys
Technologies: Spring, Gang of Four (GOF) Design Patterns, AssertJ, Agile, JUnit, Subversion (SVN), Git, Scrum, Splunk, Test-driven Development (TDD), Domain-driven Development, Angular, JMS, Dropwizard, REST, Java
- Developed core components of the back end for an online game platform with millions of active users.
- Worked on both a legacy monolithic application and a new REST microservice oriented architecture for new components.
- Contributed to crucial ideas and made them work both on the architectural and API design levels.
- Utilized quality assurance, testing (TDD), and Agile Scrum-based methodology.
- Maintained and supported live production components with Splunk.
Senior Software Develooper2012 - 2013Intel through Sii
Technologies: Git, USB, JNI, SOA, C++, C#, Java
- Developed an automated USB device testing platform as an SOA-based system.
- Implemented low-level interactions with Linux USB devices.
- Designed and implemented a web UI interface for the management of different parallel testing executions.
- Introduced test-driven development (TDD) techniques to the project.
Software Developer2010 - 2012Gdańsk University of Technology
Technologies: Windows Presentation Foundation (WPF), Image Recognition, Java, C#, C++
- Participated in an innovative project for automated disease recognition on endoscopic images.
- Analyzed and implemented the latest scientific developments in medical image recognition.
- Contributed to the preparation of scientific publications summing up the work and outcomes.
- Implemented the UI application for medical specialists to perform automated video analysis.
Java Developer2007 - 2010Wolters Kluwer Poland
- Implemented an innovative web interface application for legal system workers (lawyers, judges, and so on) to search for legal documents and company information.
- Integrated back-end services to gather data to be displayed.