toptal.com
Contact us: +1.888.867.7001
Roman Vashchegin, Algorithms Developer in Kaliningrad, Kaliningrad Oblast, Russia
Roman Vashchegin

Algorithms Developer in Kaliningrad, Kaliningrad Oblast, Russia

Member since September 5, 2013
Roman is a SharePoint and .NET developer with a proven ability to develop efficient, scalable, and fault-tolerant solutions for complex problems. He has quality experience and skills in all stages of software development, and an excellent knowledge of fundamental algorithms and data structures.
Roman is now available for hire
Hire Roman

Portfolio

  • HCL
    C#, .NET Core, React, Amazon Web Services (AWS), NHibernate
  • STO Solutions, Inc.
    Amazon Web Services (AWS), NUnit, Microsoft SQL Server, Hangfire, Backbone.js...
  • TapJets, Inc.
    Identity Server, AngularJS, Entity Framework, RabbitMQ, .NET Core

Experience

Location

Kaliningrad, Kaliningrad Oblast, Russia

Availability

Part-time

Preferred Environment

Git, Subversion (SVN), TFS, Visual Studio, Windows

The most amazing...

...thing I've done is an optimization of SQL scripts and stored procedures for HarePoint Analytics for SharePoint that prevent license refunds on more than 40000$.

Employment

  • Senior .NET Engineer

    2019 - PRESENT
    HCL
    • Developed and supported various existing components of healthcare systems.
    • Accomplished migration from .NET 4.7.2 to .NET Core (from IIS, AWS Beanstalk to ECS).
    • Migrated the front end from ASP.NET MVC to React 17 (TypeScript, Material UI, and DevExtreme).
    • Created a new back end using GraphQL (HotChocolate 12).
    • Exchanged data based on HL7 and HL7 Fhir protocols.
    • Improved, optimized, and refactored the application.
    • Wrote unit tests, integration tests, and UI tests using both Selenium and Cypress.
    Technologies: C#, .NET Core, React, Amazon Web Services (AWS), NHibernate

  • Senior .NET Engineer

    2017 - 2019
    STO Solutions, Inc.
    • Developed, from sсratch, improvements and support for different parts of a healthcare system.
    • Built the Job Portal to run tasks according to schedule: importing, exporting, transforming data between different sources.
    • Accomplished transition from MS SQL Server search to Elasticsearch that significantly boosted search results output.
    • Set up automatic builds and continuous integration.
    • Implemented cloud-based development using AWS Services (RDS, Dynamo DB, EC2, S3, Beanstalk, EKS, and ECS).
    Technologies: Amazon Web Services (AWS), NUnit, Microsoft SQL Server, Hangfire, Backbone.js, NHibernate, ASP.NET MVC

  • Web Developer

    2016 - 2017
    TapJets, Inc.
    • Developed some functionality on the main company website. Built a partner portal for air carriers.
    • Created a server API for an internal mobile application for aircraft pilots.
    • Developed a web scraper for the Avinode website on Selenium WebDriver.
    Technologies: Identity Server, AngularJS, Entity Framework, RabbitMQ, .NET Core

  • SharePoint Developer

    2014 - 2016
    Transwestern
    • Designed and supported www.transwestern.net (now team.transwestern.net) based on SharePoint 2010.
    • Designed and supported Transwestern's internal portal (https://transource.transwestern.net) based on SharePoint 2010.
    • Designed, developed, and supported an internal web application for building engineers with usage Nintex Workflow 2010. (https://inspector.transwestern.net).
    • Developed and supported a new Transwestern portal (https://www.transwestern.com). The front-end was developed on MVC4, and the back-end on SharePoint 2016.
    • Supported an internal portal for buildings (https://onboarding.transwestern.net) based on SharePoint 2010.
    • Designed, developed, and supported an internal web application for banking (check routing and cash management).
    Technologies: Nintex Workflow, ASP.NET, C#, jQuery UI, Entity Framework, SharePoint

  • Web Developer (Part-time)

    2013 - 2014
    OWYS
    • Designed and developed a portal for a language school "Expert."
    Technologies: C#, ASP.NET

  • Project Manager, SharePoint Developer (Full-time)

    2013 - 2014
    MAPILab, Ltd.
    • Optimized the SQL database, halving storage size and allowing T-SQL scripts to run ten times as fast.
    • Created a custom tool for product diagnosis and control.
    • Prevented three potential license refunds worth over $40,000.
    Technologies: T-SQL (Transact-SQL), jQuery, JavaScript, Windows Forms (WinForms), ADO.NET, ASP.NET, C#

  • SharePoint Developer (Part-time)

    2012 - 2013
    QualityPointDev
    • Extended and improved the custom SharePoint workflow for a big retailer.
    • Created several features for the "MRSK Holding" portal.
    Technologies: jQuery, ASP.NET, SharePoint, C#

  • SharePoint Developer (Full-time)

    2009 - 2012
    MAPILab, Ltd.
    • Created a custom GeoChart control tool to show visit counts and page views by country and city.
    • Implemented various tool features for exploring the SharePoint server-side object model.
    • Created a migration tool for SharePoint Analytics databases. Allowed for migration of analytics databases across environments, including between farms of different versions of HarePoint.
    • Developed a data collector and several reports for a performance reporting group. Worked with the CPU, memory, hard disk, and network.
    • Created a tool allowing users to subscribe to a report and receive it in PDF/XSLX format by email.
    • Developed a custom search engine of HarePoint HelpDesk data for SharePoint.
    • Implemented a custom data source for HarePoint HelpDesk supporting fast displaying, paging, sorting, and SharePoint list data filtering.
    • Implemented custom admin group workflow activities and conditions for HarePoint Workflow Extensions.
    Technologies: jQuery, JavaScript, ADO.NET, Windows Forms (WinForms), SharePoint, ASP.NET, C#

Experience

  • HarePoint Analytics for SharePoint
    http://www.harepoint.com/Products/HarePointAnalyticsForSharePoint/Default.aspx

    Formerly MAPILab Statistics for SharePoint, HarePoint is a web analytics solution for detailed information on the performance of SharePoint-based portals and websites. Product reports include users and their behavior, as well as usage of content, documents, list items, and search services. The product provides essential information on portal usage for IT managers, project managers, web editors, and business managers.

  • HarePoint HelpDesk for SharePoint
    http://www.harepoint.com/Products/HarePointHelpDesk/Default.aspx

    HarePoint HelpDesk for SharePoint is a ready-made customer support system for internet and intranet sites based on the SharePoint platform. It allows users to create efficient systems for processing incoming support requests. The product is easily deployed and immediately ready for use.

  • HarePoint Explorer for SharePoint
    http://www.harepoint.com/Products/HarePointExplorer/Default.aspx

    A universal accessory tool to simplify the development of solutions for Windows SharePoint Services 3.0 and Microsoft Office SharePoint Server ​2007, 2010, and 2013.

  • HarePoint Workflow Extensions
    http://www.harepoint.com/Products/HarePointWorkflowExtensions/Default.aspx

    HarePoint Workflow Extensions provides over 200 new 'ready-to-use' activities for Microsoft SharePoint workflow development. It is fully supported by all Microsoft workflow development tools and does not require any adjustment of workflows or learning of new development tools. The product benefits users of SharePoint Designer 2010, 2013, Microsoft Visual Studio 2010, 2013, and in Microsoft Visio 2010.

  • Programming Contests

    Over seven years of experience in the largest computer programming contests: (ACM ICPC, TopCoder, Google Code Jam, Facebook HackerCup, Russian CodeCup, Russian AI Cup).

    Semifinalist, Google Code Jam, 2008
    Third Diploma, Semifinal ACM ICPC (NEERC), 2007-2010
    Finalist, Russian AI Cup, 44th place (http://2012.russianaicup.ru/contest/4/standings)

  • Transwestern Public Website
    https://www.transwestern.com

    A public-facing site for Transwestern.

  • Conquer String Search with the Aho-Corasick Algorithm (Publication)
    https://www.toptal.com/algorithms/aho-corasick-algorithm
    The Aho-Corasick algorithm can be used to efficiently search for multiple patterns in a large blob of text, making it a really useful algorithm in data science and many other areas. In this article, Toptal Freelance Software Engineer Roman Vashchegin shows how the Aho-Corasick algorithm uses a trie data structure to efficiently match a dictionary of words against any text.

Skills

  • Languages

    T-SQL (Transact-SQL), C#, JavaScript

  • Frameworks

    ADO.NET, ASP.NET, .NET, NHibernate, NUnit, Entity, Bootstrap, ASP.NET Core, .NET Core, AngularJS, ASP.NET MVC 4, ASP.NET MVC, Angular, Angular Material, Hadoop, Windows Presentation Foundation (WPF)

  • Tools

    SharePoint Designer, Microsoft Visual Studio, Hangfire, Visual Studio, TFS, Subversion (SVN), Git, AWS ELB, Amazon Virtual Private Cloud (VPC), AWS SDK, Amazon Simple Queue Service (SQS), RabbitMQ, MS Silverlight

  • Paradigms

    Object-oriented Programming (OOP), Code First

  • Platforms

    SharePoint, SharePoint 2013, SharePoint 2010, SharePoint 2007, Nintex Workflow, SharePoint 2016, Windows, Amazon Web Services (AWS), Amazon EC2, Azure, Exchange Web Services

  • Other

    Algorithms, Data Structures, Office 365, SharePoint Online, DevExpress, Identity Server, Architecture

  • Libraries/APIs

    jQuery UI, jQuery, WMI, SharePoint API, REST APIs, Windows Forms (WinForms), Entity Framework, Backbone.js, Vue, Facebook API, Selenium WebDriver, React

  • Storage

    Microsoft SQL Server, Amazon S3 (AWS S3), Amazon DynamoDB, SQLite

Education

  • Master's Degree in Mathematics and Computer Science
    2005 - 2010
    Baltic Federal University of Immanuel Kant - Kaliningrad

Certifications

  • AWS Certified Solutions Architect Associate
    JANUARY 2021 - JANUARY 2024
    AWS
  • AWS Certified Cloud Practitioner
    DECEMBER 2020 - DECEMBER 2023
    Amazon Web Services
  • Hadoop Foundations - Level 2
    JUNE 2017 - PRESENT
    IBM
  • Big Data Foundations - Level 2
    MAY 2017 - PRESENT
    IBM
  • MCPD: Windows Azure Developer
    SEPTEMBER 2012 - PRESENT
    Microsoft
  • MCPD: Windows Developer 4
    FEBRUARY 2012 - PRESENT
    Microsoft
  • MCPD: Web Developer 4
    NOVEMBER 2011 - PRESENT
    Microsoft
  • MCPD: Enterprise Application Developer 3.5
    OCTOBER 2011 - PRESENT
    Microsoft
  • MCITP: SharePoint Administrator 2010
    JULY 2011 - PRESENT
    Microsoft
  • MCPD: SharePoint Developer 2010
    JUNE 2011 - PRESENT
    Microsoft

To view more profiles

Join Toptal
Share it with others
Hire the top 3% of freelance developers TM