Publication
Conquer String Search with the Aho-Corasick Algorithm
https://www.toptal.com/developers/algorithms/aho-corasick-algorithm
Roman is currently unavailable
Roman Vashchegin
Verified Expert in Engineering
Algorithms Developer
Kaliningrad, Kaliningrad Oblast, Russia
Toptal member since September 5, 2013
Bio
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.
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
- Algorithms - 12 years
- Transact-SQL (T-SQL) - 11 years
- .NET - 10 years
- C# - 10 years
- SharePoint - 8 years
- ASP.NET MVC 4 - 5 years
- AWS SDK - 3 years
- .NET Core - 3 years
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$.
Work Experience
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: Transact-SQL (T-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.aspxFormerly 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.aspxHarePoint 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.aspxA 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.aspxHarePoint 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)
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)
Education
2005 - 2010
Master's Degree in Mathematics and Computer Science
Baltic Federal University of Immanuel Kant - Kaliningrad
Certifications
JANUARY 2021 - JANUARY 2024
AWS Certified Solutions Architect Associate
AWS
DECEMBER 2020 - DECEMBER 2023
AWS Certified Cloud Practitioner
Amazon Web Services
JUNE 2017 - PRESENT
Hadoop Foundations - Level 2
IBM
MAY 2017 - PRESENT
Big Data Foundations - Level 2
IBM
SEPTEMBER 2012 - PRESENT
MCPD: Windows Azure Developer
Microsoft
FEBRUARY 2012 - PRESENT
MCPD: Windows Developer 4
Microsoft
NOVEMBER 2011 - PRESENT
MCPD: Web Developer 4
Microsoft
OCTOBER 2011 - PRESENT
MCPD: Enterprise Application Developer 3.5
Microsoft
JULY 2011 - PRESENT
MCITP: SharePoint Administrator 2010
Microsoft
JUNE 2011 - PRESENT
MCPD: SharePoint Developer 2010
Microsoft
Skills
Libraries/APIs
jQuery UI, jQuery, WMI, SharePoint API, REST APIs, Windows Forms (WinForms), Entity Framework, Backbone.js, Vue, Facebook API, Selenium WebDriver, React
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, Microsoft Silverlight
Languages
Transact-SQL (T-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)
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
Storage
Microsoft SQL Server, Amazon S3 (AWS S3), Amazon DynamoDB, SQLite
Other
Algorithms, Data Structures, Office 365, SharePoint Online, DevExpress, Identity Server, Architecture
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