Alexander Velichkin, Developer in Voronezh, Voronezh Oblast, Russia
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Alexander Velichkin

Verified Expert  in Engineering

.NET Developer

Voronezh, Voronezh Oblast, Russia
Toptal Member Since
May 23, 2017

Alexander is a .NET developer offering more than eight years of experience in leading small teams designing web, desktop, and mobile applications with a passion for .NET Core, Angular, and DevOps. Alexander excels at delivering reliable and innovative strategies and solutions that enhance the performance of existing applications and drive business growth.

Portfolio (via Toptal)
Azure DevOps, Git, RabbitMQ, jQuery, Classic ASP, Microsoft SQL Server...
Atos IT Solutions and Services, LLC.
Microsoft SQL Server, TFS, Git, Model View ViewModel (MVVM), Prism...
Donation Kiosk (via Toptal)
JSON, XAML, Git, Windows Presentation Foundation (WPF)




Preferred Environment

TFS, Git, DataGrip, Visual Studio Code (VS Code), Visual Studio

The most amazing...

...project performance I've analyzed and improved was for a web-based application with heavy reports and thousands of users working simultaneously.

Work Experience

Senior C# .NET Developer

2018 - PRESENT (via Toptal)
  • Eliminated spam by creating a Regex-based, back-end service that communicates with web applications via RabbitMQ and automatically filters user content.
  • Integrated third-party services Google ReCaptcha, Analytics, AdSense and Taboola Ads, Pingdom, and SendGrid with a web application—resulting in increased revenue, performance, and accessibility.
  • Increased a web application's load speeds by 40% that is running Classic ASP, ASP.NET WebForms, DevExpress, jQuery, and MS SQL.
  • Developed tools for admins to create web pages using DevExpress HTML editor without involving a programmer.
  • Expanded and scaled development capabilities by introducing a new CI/CD process using Azure DevOps and set up new development and testing environments for existing web applications using AWS.
  • Minimized downtime maintaining web applications and background services on AWS EC2 (Windows Servers) and RDS (MS SQL Server) machines.
Technologies: Azure DevOps, Git, RabbitMQ, jQuery, Classic ASP, Microsoft SQL Server, Entity Framework, DevExpress, ASP.NET Web Forms, C#

Senior C# .NET and Xamarin.Forms Developer

2016 - 2018
Atos IT Solutions and Services, LLC.
  • Developed web application using ASP.NET Web Forms and DevExpress components automating workflows for global real estate company. App tracked CapEx and OpEx movement and generated PDF and XLS reports.
  • Streamlined operations building modules for Excel reporting using ComponentPro, developing Windows service to perform background long-processing operations, and creating Xamarin.Forms applying UI components.
  • Optimized data sharing designing multi-platform library used by both Xamarin.Forms and ASP.NET MVC projects to synchronise, serialize, encrypt, and validate data sent between Android smartphones and server.
  • Developed auto-synchronizing library using MS SQL Server and local MySQL databases enabling end-users to work offline and synchronise data with a server-side database at later intervals.
  • Improved XLS and PDF reporting performance by reducing their generation time up to 50%.
  • Designed and created a VBA MS Access application that is used by several users simultaneously with reports and authentication.
Technologies: Microsoft SQL Server, TFS, Git, Model View ViewModel (MVVM), Prism, Xamarin.Forms, PDFtk, ComponentPro, DevExpress, SQL Server 2012, ADO.NET, Web Forms, ASP.NET, C#

Senior WPF and C# Developer

2017 - 2017
Donation Kiosk (via Toptal)
  • Produced a WPF application for touchscreens customizing controls such as buttons, labels, and list views.
  • Saved countless hours adding auto-updating functionalities to a desktop WPF application using a PHP back end via JSON.
Technologies: JSON, XAML, Git, Windows Presentation Foundation (WPF)

Senior C# .NET Developer

2016 - 2017
  • Programmed a desktop WPF application with an Intel RealSense camera and web-based admin panel using ASP.NET MVC and MS SQL Server.
  • Created a WCF service for interaction between a WPF application and a web-based admin panel for remote access.
Technologies: Microsoft Kinect, Git, Entity Framework, Microsoft SQL Server, Intel RealSense, Windows Communication Foundation (WCF), Windows Presentation Foundation (WPF), ASP.NET MVC, .NET, C#

Load-testing Engineer

2016 - 2016
Home Credit and Finance Bank, LLC.
  • Enhanced performance by creating test plans for load-testing using JMeter and scripts with Python 3 for a log file analysis.
  • Prepared sample data for test plans using the Oracle database.
Technologies: Git, Oracle, Python 3, Apache JMeter

ActionScript 3 and C# .NET Developer

2012 - 2016
BI-Leasing, LLC.
  • Streamlined operations, architecting internal application to automate processes with role-based access using PostgreSQL, ASP.NET Web API, AngularJS, and FastReport .NET.
  • Developed an advertisement application using Kinect 2, WPF, and ASP.NET MVC boosting visibility.
  • Built an internet kiosk application with WPF permitting on-line banking for existing customers.
  • Created a cartographic application using the OpenStreetMap API and ActionScript 3.0 for Windows, Android, and iOS platforms.
  • Accelerated knowledge sharing developing a library of ActionScript 3 UI components were used by multiple teams across different projects.
Technologies: Visual Studio, Subversion (SVN), Git, ActionScript 3, PostgreSQL, Microsoft SQL Server, Entity Framework, Microsoft Kinect, FastReport, AngularJS, LINQ, Web API, Windows Presentation Foundation (WPF), .NET, C#

K-Visor is an interactive Windows application that gives you a more effective and convenient way to deliver your products or services in places with huge attendance numbers.

K-Visor can be used do attract passers-by. An image from display starts interacting with them, grabbing their attention and enabling to look through the information about goods and services with several simple gestures.

Kiosk Application

I developed a WPF application for touchscreen displays to perform payments to different organizations with VISA, MasterCard, AmEx payment cards. It has multiple features such as adding email subscriptions and managing the account via a web portal.

The application is delivered to clients with a touchscreen display and all the necessary hardware.

Data Sync Library

I developed a .NET-based library to sync data across the desktop application (using local MySQL installation), server web application (using MS SQL Server installation) and Xamarin.Forms application (using SQLite). All applications listed above were transferring data between each other via a RESTful back end (ASP.NET Web API).

Background Service

I developed a background service which is called to perform background operations. One of these operations was a task to automatically delete spam content added by users. This task is based on regular expression rules that are managed with a web interface.

This task made it easier for moderators to work.
2011 - 2013

Master of Science (MS) Degree in Information Systems and Technologies

Voronezh State Technical University - Voronezh, Russia

2007 - 2011

Bachelor of Science (MS) Degree in Information Systems and Technologies

Voronezh State Technical University - Voronezh, Russia


Become an ASP.NET Core Developer



ASP.NET Core New Features



ASP.NET Core: Middleware



ASP.NET Core: Razor Pages



ASP.NET Core: Security



ASP.NET Core: Test-driven Development



Building and Securing RESTful APIs in ASP.NET Core



Deploying ASP.NET Core Applications



Learning Entity Framework Core



Learning ASP.NET Core MVC

LinkedIn Learning


Microsoft Certified Solutions Associate



SendGrid API, Web API 2, Web API, JSON API, Entity Framework, Selenium WebDriver, Linq2SQL, ASPX, REST APIs, OpenStreetMap API, jQuery, LINQ, Fluent API, SignalR, AutoMapper, OpenID, Node.js


LINQ to SQL, DotTrace, Visual Studio .NET, Visual Studio 2015, ReSharper, TFS, Visual Studio 2013, Microsoft Visual Studio, Git, Visual Studio 2019, SendGrid, Visual Studio, Bitbucket, C#.NET WinForms, GitHub, WebStorm, Apache JMeter,, JetBrains Rider, DataGrip, Azure DevOps Services, PDFtk, Prism, RabbitMQ, Webpack, Gulp, Subversion (SVN), FastReport, Jira


ASP.NET Web Forms, .NET, Entity 6, Windows Presentation Foundation (WPF), Microsoft Kinect, Razor Pages, MVC Razor, ASP.NET MVC 5, .NET 5, .NET 2, .NET 3, ASP.NET MVC 6, NUnit, ASP.NET Core MVC, Entity 5, ASP.NET Core, ASP.NET, ASP.NET MVC, ASP.NET Core 2, .NET 4, .NET Core, Entity Framework Core, ASP.NET Web API, Newtonsoft JSON, ADO.NET, AngularJS, ASP.NET MVC 4, Bootstrap, Razor, ASP.NET Identity, Angular, Classic ASP


Active Server Pages (ASP), C#.NET, C#, SQL, HTML5, ASP.NET Razor, JavaScript, XML, Python 3, CSS, HTML, TypeScript, Visual Basic for Applications (VBA), Visual Basic .NET (VB.NET), Excel VBA, Python, ActionScript 3, XAML


Visual Studio 2017, Amazon EC2, Visual Studio Code (VS Code), Windows, Oracle, ComponentPro, Amazon Web Services (AWS), Azure


SQL Server 2012, SQL Server 2014, SQL Server 2010, SQL Server 2008 R2, SQL Server 2016, SQL Server 2017, SQL Server 2005, Databases, Microsoft SQL Server, PostgreSQL, JSON, SQLite, MySQL, Web Forms


Dependency Injection, REST, RESTful Development, Code First, Database First, Waterfall Development, Azure DevOps, Back-end Architecture, Test-driven Development (TDD), Unit Testing, Model View ViewModel (MVVM)


GitFlow, Xamarin.Forms, DevExpress, Windows Communication Foundation (WCF), Intel RealSense, DevExpress Controls, Ajax, APIs, Back-end, Back-end Development, Web Development, Full-stack, EF6 Code First, DI

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