Rafal Gierusz
Verified Expert in Engineering
Back-end Developer
Rafal is a highly accomplished international business and technical leader with over 15 years of progressive technical experience in positions such as system and solution architect, head of development, and CIO. He is a Java technology specialist focusing on multithreaded, distributed, high-performance, and fail-proof solutions.
Portfolio
Experience
Availability
Preferred Environment
Java
The most amazing...
...system I’ve created is a cutting-edge VoIP system for 16 EU countries that works with sophisticated real-time business-level flow monitoring systems.
Work Experience
Lead Development Engineer and Lead Solution Architect
BTC Markets
- Served as an engineer for the Australian cryptocurrency stock exchange. They are a high-tech fintech company with high demands for performance, scalability, accessibility, and flexibility.
- Implemented and created architecture, maintained the stock exchange core system, researched new solutions to challenges, being mostly responsible for concurrency and performance aspects of the software, and led and helped team members.
- Led the core trading system development, designing concurrent and multithreaded systems and developing unique solutions in the fintech market.
Owner and CEO
Imbue Lab
- Contributed to distributed solutions for the US health industry, including authorization and authentication solutions based on OpenSSO and OpenAM frameworks.
- Participated in the development of a real-time business-level flow and transaction monitoring technology proven in several highly demanding trading environments where sub-millisecond latency is deemed important.
- Used cutting-edge techniques, including distributed caching, complex event processing, and distributed computing. Designed architecture and innovative, distributed network framework based on Netty, RestExpress, and other top technologies.
- Created architecture and chose technologies for various frameworks and standalone solutions.
- Gathered stakeholders' requirements and executed sustainable solutions based on their requirements.
Senior Java Back-end Developer
Yahoo! - Native Advertising
- Migrated distributed solutions from in-house datacenter to AWS, including analysis and change of existing architectural approach and upgrade and transition from legacy technology stack to modern solutions and frameworks.
- Acted as a mentor to other team members on more advanced Java solutions.
- Participated in the design of new solutions for AWS migration.
Atlassian Jira/Confluence Developer
Resolution Reichert Network Solutions GmbH
- Worked directly with Jira, Bitbucket, and Confluence cores to create new user management-related plugins.
- Worked on session activity and used deactivation features not provided by Atlassian by default.
- Played a role of a mentor for general Java solutions.
Chief Information Officer
Sigato Group
- Created the IT strategy and oversaw all aspects of software development processes.
- Collaborated with internal and external stakeholders in new business acquisition and business innovation.
- Supervised software engineering and technical infrastructure teams.
Senior Development Engineer and Solution Architect
Velocimetrics
- Made real-time business-level flows and transaction monitoring technology proven in several highly demanding trading environments. Focused on submillisecond latency, cutting-edge techniques, distributed caching, and distributed computing.
- Built a set of network protocol decoders for core servers. Worked directly with multiple major investment banks.
- Helped create a system capable of processing 250,000 TPS in real time.
Head of Development
Objectivity
- Led a development team of approximately 30 people and an architecture team of around six.
- Took responsibility for approving technical software solutions and mentored architects and developers.
- Took an active part in the development work and visited clients to discuss technical aspects of created software.
- Introduced Agile methodologies, mainly Scrum, and acted as a scrum master and product owner.
Experience
Validators
It's an innovative approach, not met anywhere else, fitting all the needs of such validators. It can be used without effort or clash with inheritance.
Skills
Languages
UML, Spring Expression Language (SPEL), Java, Java 8, SQL, Java SE, Kotlin, PHP, GraphQL, JavaScript, SAML
Frameworks
Spring, JPA, Hibernate, Netty, Mockito, JUnit, Swagger, Spring Boot, Spring Microservice, Spring JDBC, Angular, Hadoop, Spark
Libraries/APIs
REST APIs, Drupal API, SWT, jQuery, Backbone.js, WordPress API
Tools
Apache Maven, Gradle, Eclipse IDE, IntelliJ IDEA, Git, Hudson, Eclipse RCP, RabbitMQ, ForgeRock, Oracle OpenSSO, Microsoft Power BI, Jira
Paradigms
Concurrent Programming, Management, Agile, Design Patterns, REST, Microservices, Requirements Analysis, Microservices Architecture, Pair Programming, Test-driven Development (TDD), Distributed Computing, DevOps, Distributed Programming
Platforms
Magento, Eclipse, JBoss, WebSphere, Drupal, Jakarta EE, Amazon Web Services (AWS), Linux, Windows, Blockchain, Apache Kafka, Java EE, OpenAM, WordPress, JavaFX, Oracle, Azure
Storage
Relational Databases, Databases, Microsoft SQL Server, MySQL, PostgreSQL, Redis, NoSQL, MongoDB, Elasticsearch, HDFS
Other
Team Mentoring, Leadership, Scrum Master, APIs, Distributed Systems, Back-end, Technical Hiring, Source Code Review, Code Review, Task Analysis, Architecture, Software Design, Integration, API Integration, Low Latency, Solution Architecture, System Architecture, Software Architecture, Technical Diagrams, API Gateways, Distributed Applications, Interviewing, Single Sign-on (SSO), Payment Gateways, Legacy Code, Legacy Software, Data Processing, Big Data, Fintech, Cloud, Large Scale Distributed Systems, HTTP, Transmission Control Protocol (TCP), Algorithms, SOAP, Amazon RDS, Servers, Trading Applications, Multithreading, Performance, Global Banking, Online Banking, Trading, Forex Trading, Concurrency, Software, Computer Science, Information Technology, Engineering, Software Engineering, CI/CD Pipelines, Validation, WebSockets
Industry Expertise
Trading Systems, Healthcare
Education
Master of Engineering Degree in Computer Science and Management
Wroclaw University of Technology - Wroclaw, Poland
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