About

Work Experience

• Senior Engineer, 

  Mar, 2021 - Sep, 20216 months

  Developing Demand Side Platform of Real Time Bidding system for our Irish client, Verizon Media

• Software Engineer, 

  Oct, 2019 - Jan, 20203 months

  Java Developer for Verifone. Verifone is a company which provides technology for electronic payment transactions and value-added services at the point-of-sale

• Software Engineer, 

  Apr, 2019 - Aug, 20194 months

  Java Developer for Refinitiv project of Metadata Registry.

  • Rewritten Dependency Injection Guice Module enhancing reuse through domain-specific language

  • Designed and implemented Proof of Concept Json Transformer microservice based on Jackson Generic Polymorphic Annotation-driven Deserialization Model addressing Object-to-Semistructured Impedance Mismatch problem

  • Investigated Amazon AWS Lambda service, implemented exemplary setup integrating with client's AWS architecture, and shared the knowledge with the team

  • Researched Datadog monitoring tool and performed presentation in front of the team

  • Created Jira Stories with explorations on alternative open-source solutions and cutting-edge Internet standards. Suggested usage of jq Json Processor as DSL with Json Schema for validation, or for Java-based solution MapStruct for Bean Mapping with Hibernate Validator

  • Implemented Convention over configuration framework based on Jackson Dataformat Properties library

  • Wrote Unit Tests with auto-injected mocks and wrote Component test cases

  • Responded some questions about Jackson on Stackoverflow.com, gaining privileges

• Software Engineer, 

  Jul, 2018 - Apr, 20199 months

  Bench. I was learning stuff while waiting for the project assignment.

  • Watched all of Category Theory for Programmers I, II and III lecture series by Bartosz Milewski, 26 lectures in total

  • Watched Parallel and Concurrent Haskell by the same author, 8 lectures

  • Read "Haskell Programming from First Principles", solving all exercises along the way

• Java Developer, 

  Jan, 2017 - Apr, 20181 year 3 months

  Mobile Payment Solution built on top of Play and Cassandra, supported by AWS platform

  • Managed AWS fleet of EC2 instances

  • Managed Docker multi-container application

  • Migrated column families to Cassandra with Talend Big Data ETL tool, CQL COPY command

  • Created, Updated and solved issues with Jenkins jobs for project build and deployment

  • Used GitLab for Merge Request creation and review (active and passive)

  • Refactored, debugged, tracked bugs, tested solutions in development environment, analyzed logs

  • Tested with jUnit, MockServer, CassandraUnit, ScalaTest, Advanced REST Client

  • Used Jira for task management

  • Discussed tasks on daily meetings

  • Time tracked tasks with Upwork Tracker and TimeDoctor

  • Implemented usage of external APIs

  • Documented REST APIs with stoplight.io

  • Displayed Grafana infrastructure monitoring checks sent by collectd

  • Data Access Object layer to Apache Cassandra database through Datastax Java Driver, Outworkers Phantom Scala Driver, Administering it with Datastax DevCenter

  • Set up ssh tunnels to AWS instance

  • Researched problems with the help of Stack Overflow and Google in general

  • Created documentation in Confluence

  • Linux tools like vi, grep, nc, apt-get, crontab

• Java Programmer, 

  Jun, 2015 - Aug, 20152 months

  Nation-wide emergency notification system for private security company Responsibilities:

  • Creating REST web services in Spring MVC

  • Multitier object-relational mapping of PostgreSQL database with JOOQ, DAOs, Repositories

  • Creation of interactive windows, dialogs, tables and other frontend elements with input handling in JavaFX 8

  • Using Java 8 functional programming features throughout the project

  • Taking part in daily stands

  • Continuous integration with Jenkins

• Programmer, 

  Jan, 2015 - Mar, 20152 months

  Responsibilities:

  • Implementing visual invterface of cable TV sales system in Flex according to requirements

  • Load testing of web application with JMeter

  • Analyzing memory leakage using Eclipse Memory Analyzer (MAT)

  • Taking part in daily stands, planning and reviews of stories and tasks according to Scrum methodology

• Programmer, 

  Nov, 2012 - Jul, 20141 year 8 months

  I was developing Real-Time Bidding system, which is about buying advertising inventory on a real time millisecond basis. We were observing people by tracking cookies what they were looking for on e-commerce sites, what are they preferences, what might be their age, gender and so forth. Through that, we were able to build statistical model for cost effectiveness valuation, which used Hadoop platform for massive parallel computations. Outside of demand side platform we offered our clients clean and elegant campaign management website

  • Implementing large XML feeds' SAX streaming parsers

  • Creating servlets and REST web services in accordance to requirements

  • Dependency Injection with Google Guice

  • Creating PostgreSQL database structure with corresponding entity and domain classes with EclipseLink

  • Mapping beans between tiers using Dozer

  • Instrumenting running application with JMX

  • Investigating errors and debugging with Eclipse

  • Creation and modification of campaign management frontend written in PHP, HTML, CSS, JS, JQuery

  • Creating, running and monitoring Pig scripts on Hadoop cluster

  • Creating unit tests in TestNG and Mockito

  • Taking part in daily stands, planning and reviews of stories and tasks according to Scrum methodology

• Java Programmer, 

  Oct, 2011 - Feb, 20124 months

  • Design and implementation of a mobile phone game in company's framework and J2MEPolish

  • Modeling Newtonian physics in-game

  • Multithreading through synchronization

• Java Apprenticeship, 

  Aug, 2011 - Sep, 20111 month

  • Development of restaurant tables booking website with Play! Framework

  • Development of groupon offers aggregator with Play! Framework

Skills

Education

Interests

References