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Sergii Zagriichuk

Sergii Zagriichuk

Ukraine
Member since October 15, 2012
Sergii is a senior Java developer with over a decade of proven ability to create architecture and develop efficient, scalable and fault-tolerant solutions for complex tasks. He can develop software or lead a team with ease.
Sergii is now available for hire
Portfolio
  • DataCradle
    Multithreading, Collections, JSE, JEE, TCP/IP, NIO, Netty...
  • NDA
    Java, XML, Android, SQL
  • UBS
    Multithreading, Collections, Java Core, JMS, TCP/IP, XML, HTML, JavaScript, SQL
Experience
  • Java, 11 years
  • JUnit, 11 years
  • XML, 7 years
  • SQL, 5 years
  • Guava, 4 years
  • HTML5, 4 years
  • C#, 3 years
  • Android, 2 years
Ukraine
Availability
Part-time
Preferred Environment
Windows, Mac OS X, Linux, IntellJ IDEA, Git
The most amazing...
...thing I've developed is a solution for storing data in a distributed environment with ability to connect to any node for getting all information and data.
Employment
  • Java Architect
    DataCradle
    2011 - PRESENT
    • Analyzed issues from the customer.
    • Designed software architecture.
    • Developed common architecture using OSGI (Eclipse Gemini, Spring DM).
    • Worked on the development of a module for storing data.
    • Developed a module to manage data.
    • Built architecture/modules for high-load data performance.
    • Developed a module for communication between client and server based on the Netty framework.
    • Worked on a communication/serialization protocol using Google Protocol Buffer.
    • Made a secure module for authentication/authorization clients on the cloud.
    • Built a virtual file system based on the FUSE driver.
    • Developed Android prototypes for cloud storage systems.
    Technologies: Multithreading, Collections, JSE, JEE, TCP/IP, NIO, Netty, Google Protocol Buffer, Eclipse Gemini, Spring 3, OSGI, Android
  • Senior Java Developer
    NDA
    2011 - 2012
    • Built an Android app for the banking business.
    • Created an Android app for business task scheduling.
    Technologies: Java, XML, Android, SQL
  • Senior Java Developer
    UBS
    2011 - 2011
    • Analyzed issues from customers.
    • Designed software architecture.
    • Developed a module for received transactions.
    • Worked on the logic for enriched transactions.
    • Built several database queries and stored procedures.
    Technologies: Multithreading, Collections, Java Core, JMS, TCP/IP, XML, HTML, JavaScript, SQL
  • Technical Leader
    NICE Systems
    2009 - 2011
    • Analyzed issues from the customer.
    • Created functional specifications of the application.
    • Designed software architecture.
    • Created web services in duplex mode using WCF.
    • Developed a module to support SSL in the application.
    • Created a client to show pop-up windows followed by a sound.
    • Created Installation and User Manual guides.
    • Developed database structures, queries, stored procedures, views, and triggers.
    • Managed a team of five developers.
    Technologies: Multithreading, Collections, Java and .NET Core, TCP/IP, HTML, XML, JavaScript, SQL
  • Senior Java Developer
    Epam Systems
    2008 - 2009
    • Analyzed functional specifications and requirements of the application.
    • Designed software architecture based on specifications and user requirements.
    • Designed and developed a FIX validation module to check FIX messages in runtime.
    • Created a XMLBinding module to serialize XML templates/dictionaries into Java objects in runtime.
    • Created a FAST engine module for encoding and decoding FIX messages into FAST messages and back again.
    Technologies: Multithreading, Collections, Java Core, NIO, TCP/IP, FIX and FAST Protocols
  • Java Developer
    Aricent
    2003 - 2008
    • Analyzed functional specifications and requirements of the application.
    • Designed software architecture based on specifications and user requirements.
    • Designed and implemented the login module for access by Power Scribe's Dictation client and integration with existing C++/ActiveX objects.
    • Designed and developed Order Entry and Coding Manager modules.
    • Designed and implemented the login module for access by Administrator, OrderEntry, and CodingManager mlients.
    • Designed and implemented the VisitEntry module.
    • Developed stored procedures and views for the MS SQL database.
    • Developed a module to load data from HL7 parse and provisions for other modules.
    • Developed web services using frameworks Axis 1.4 and Axis 2.
    • Designed and implemented building processes using Apache Ant 1.6.
    Technologies: Multithreading, Collections, Java Core, Swing, XML, Spring, Servlets, HL7, SQL
Experience
  • DataCradle (Development)
    http://datacradle.com/

    DataCradle-Cloud is cutting-edge technology of the cloud to deliver unlimited data storage with built-in data protection and provisioning, radically simplifying data storage and protection for business and home.

  • NICE Systems (Development)
    http://www.nice.com/

    NICE Bridge, This project is Client/Server application based on .NET WCF Duplex technology. It provides for customers functionality to monitor Record on Demand events on the NICE Perform System.

Skills
  • Languages
    Java, XML, C#, Scala, HTML5, SQL
  • Frameworks
    Spring, Google Protocol Buffer, JUnit, OSGi, Eclipse Gemini, Netty
  • Libraries/APIs
    Guava, Java Collections
  • Paradigms
    Concurrent Programming, Waterfall Development, Object-oriented Programming (OOP), Test-driven Development (TDD), Agile Software Development
  • Platforms
    Java EE, Android, Linux, Windows, Oracle, Mac OS
  • Storage
    MySQL, Cassandra, Neo4j, Microsoft SQL Server
  • Other
    Apache Commons
Education
  • Bachelor and Master Degrees degree in Faculty of Information Technology and Computer Engineering
    Kiev National Technical University - Kiev
    1999 - 2004
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