Sergey Kolodiy, .NET Developer in Moscow, Russia
Sergey Kolodiy

.NET Developer in Moscow, Russia

Member since October 27, 2014
Sergey is a software engineer with extensive development experience in the .NET technology stack, with strong architecture and coding skills. He loves to work on complex and business-critical tasks with full involvement, high productivity, and great enjoyment. He is a big fan of clean, testable, and maintainable code and has worked on a number of successful projects ranging from small startups to complex enterprise applications.
Sergey is now available for hire

Portfolio

  • Independent Project
    C#, .NET 6, Telegram Bot API, Trading, Stock Price Analysis, .NET...
  • BoostLingo, LLC
    JavaScript, C#.NET, AngularJS, .NET Core, Entity Framework Core, Web...
  • Shrader Group LLC
    C#, .NET, Visual Studio Team Services (VSTS), Microsoft SQL Server, REST APIs...

Experience

Location

Moscow, Russia

Availability

Part-time

Preferred Environment

Git, VS Code, Visual Studio, Windows, .NET, Microsoft Visual Studio, C#, C#.NET, Visual Studio Code

The most amazing...

...application I've created is a tool that generates an OData REST API and a single-page web UI for any relational SQL database.

Employment

  • Software Engineer | Analyst

    2019 - PRESENT
    Independent Project
    • Designed and developed a successful algorithmic trading solution.
    • Implemented various data analytics algorithms and several trading strategies.
    • Integrated the solution with Telegram bot API for remote management.
    Technologies: C#, .NET 6, Telegram Bot API, Trading, Stock Price Analysis, .NET, Microsoft Visual Studio, ASP.NET Web API, Unit Testing, REST, LINQ, .NET Core, Algorithmic Trading, Object-oriented Programming (OOP), C#.NET, Azure, Microsoft Azure, SQL, APIs, Task Analysis, Visual Studio, Back-end, REST APIs, CI/CD Pipelines, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Markdown, Functional Programming, Object-oriented Design (OOD), SQL Server Management Studio, Microsoft SQL Server, Design Patterns, Visual Studio Code, Fiddler, Debugging, Mathematics, Software Architecture, Web API
  • Senior Software Engineer

    2018 - 2022
    BoostLingo, LLC
    • Worked on new business-critical features in a fast-paced environment, fixed bugs, and refactored legacy code.
    • Worked on all aspects of the system, including business logic workflows implementation, task analysis, third-party systems and services integration, back-end APIs and web client development, and much more.
    • Made a performance audit and improved the performance of critical back-end APIs.
    • Implemented a bunch of useful ASP.NET Core extensions and middleware, such as online user tracking and CSP handling.
    • Achieved such exceptional project results with a Toptal client that I was bought out and started working with the client directly as a remote contractor.
    Technologies: JavaScript, C#.NET, AngularJS, .NET Core, Entity Framework Core, Web, Twilio API, Twilio Programmable Video, Zoom, .NET, Microsoft Visual Studio, C#, ASP.NET Web API, Unit Testing, REST, LINQ, ASP.NET Core, Microsoft SQL Server, Scrum, Git, Object-oriented Programming (OOP), HTML, Azure, Microsoft Azure, SQL, .NET 6, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, REST APIs, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Jira, Markdown, Functional Programming, Object-oriented Design (OOD), SQL Server Management Studio, Refactoring, Design Patterns, Visual Studio Code, Fiddler, Debugging, Mathematics, UI, UX, Front-end, RESTful APIs, Software Architecture, Web API
  • Senior Software Engineer

    2017 - 2018
    Shrader Group LLC
    • Designed and implemented an ETL pipeline to migrate a large amount of data from a legacy Drupal-based system to the new SQL Azure database.
    • Performed a codebase audit and fixed some serious issues related to security, database versioning, testability, and overall code quality.
    • Made a performance audit and improved the performance of critical APIs up to ten times.
    • Implemented continuous integration pipelines in VSTS.
    Technologies: C#, .NET, Visual Studio Team Services (VSTS), Microsoft SQL Server, REST APIs, Entity Framework Core, ASP.NET Core, .NET Core, Data Integration, ETL, SQL Server Integration Services (SSIS), Microsoft Visual Studio, Unit Testing, REST, LINQ, Git, Object-oriented Programming (OOP), C#.NET, Azure, Microsoft Azure, SQL, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, CI/CD Pipelines, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Microsoft Data Transformation Services (now SSIS), Object-oriented Design (OOD), SQL Server Management Studio, Refactoring, Design Patterns, Visual Studio Code, Fiddler, Debugging, RESTful APIs, Software Architecture, Web API
  • Senior Software Engineer

    2016 - 2017
    FRONTSTEPS
    • Implemented a centralized security token service and a granular permission-based authorization system for ASP.NET Core instead of coarse-grained role-based authorization.
    • Implemented an automated voicemail system with voice recognition so homeowners can register their visitors by phone, and community guards will be immediately notified about new guest invitations.
    • Built a notification API to deliver various notifications to the platform users.
    • Implemented a bunch of useful ASP.NET Core extensions and middleware, such as a distributed cache with fallback logic.
    • Worked on CI-related stuff, including continuous delivery pipelines and package management.
    • Worked on payment systems integration, back-end APIs, web and desktop clients, and more.
    Technologies: C#, .NET, Visual Studio Team Services (VSTS), Microsoft SQL Server, SendGrid, PubNub, Twilio, Identity Server, OAuth, Microservices, REST APIs, Entity Framework Core, ASP.NET Core, .NET Core, Microsoft Visual Studio, ASP.NET Web API, Unit Testing, REST, LINQ, Scrum, JavaScript, Git, Twilio API, Object-oriented Programming (OOP), HTML, C#.NET, Azure, Microsoft Azure, SQL, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, CI/CD Pipelines, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Jira, Functional Programming, Object-oriented Design (OOD), SQL Server Management Studio, Refactoring, Design Patterns, Visual Studio Code, Fiddler, Debugging, Redis, RESTful APIs, Software Architecture, Web API
  • Senior Software Engineer

    2014 - 2016
    Infor
    • Implemented an administration API with AWS integration for automatic code deployment.
    • Created an administration REST service and AngularJS-powered single-page web application on top of it.
    • Worked on new features, fixed bugs, and refactored legacy code.
    Technologies: .NET, Moq, MSTest, Bootstrap, AngularJS, Windows Communication Framework (WCF), OWIN, ASP.NET Identity, ASP.NET Web API, C#, Microsoft Visual Studio, Unit Testing, REST, LINQ, Microsoft SQL Server, Scrum, JavaScript, Object-oriented Programming (OOP), HTML, C#.NET, SQL, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, REST APIs, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Jira, Functional Programming, Object-oriented Design (OOD), SQL Server Management Studio, Refactoring, Design Patterns, Fiddler, Debugging, Front-end, RESTful APIs, Software Architecture, Web API
  • Software Engineer

    2014 - 2014
    Freelance
    • Implemented a web application for real-time server performance monitoring.
    • Created a chart control with the D3.js library and helped the client avoid using commercial charting libraries.
    • Implemented a REST API for one of the projects from scratch.
    • Implemented an efficient parallel data parser for MediaWiki API.
    Technologies: C#, .NET, Moq, MSTest, Bootstrap, D3.js, jQuery, AngularJS, ASP.NET Web API, SignalR, ASP.NET, ASP.NET MVC, Microsoft Visual Studio, Unit Testing, REST, LINQ, JavaScript, Object-oriented Programming (OOP), HTML, C#.NET, SQL, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, REST APIs, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Object-oriented Design (OOD), SQL Server Management Studio, Microsoft SQL Server, Refactoring, Design Patterns, Fiddler, Debugging, RESTful APIs, Software Architecture, Web API
  • Senior Software Engineer

    2013 - 2014
    T-Systems International
    • Implemented new functionalities and business logic for desktop and web applications.
    • Helped integrate the software system with external services like SAP and others.
    • Provided on-site application support and helped resolve issues on the customer's site.
    • Helped to meet a bunch of important deadlines during the project's lifetime.
    • Made a presentation on code review and best practices applicable to it.
    Technologies: .NET, jQuery, ASP.NET MVC, Entity Framework, Windows Communication Framework (WCF), Windows Presentation Foundation (WPF), C#, Microsoft Visual Studio, Unit Testing, REST, LINQ, ASP.NET Web API, Microsoft SQL Server, Scrum, JavaScript, Object-oriented Programming (OOP), HTML, C#.NET, SQL, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, REST APIs, Architecture, SOLID Principles, Dependency Injection, Inversion of Control, Jira, Functional Programming, Object-oriented Design (OOD), SQL Server Management Studio, Refactoring, Design Patterns, Fiddler, Debugging, Front-end, RESTful APIs, Software Architecture, Web API
  • Software Engineer

    2010 - 2013
    ETNA Software
    • Designed and developed a bunch of core system components: back-end APIs, services, and libraries for the sogotrade.com trading platform.
    • Implemented and supported streaming and load balancing solutions for real-time market data delivery.
    • Integrated back-end components with the customer's service monitoring system.
    • Developed a market data provider with a web-based admin panel and AmiBroker integration.
    • Introduced unit testing practices and testable code concepts to the project.
    Technologies: .NET, Moq, MSTest, NUnit, ASP.NET MVC, Microsoft SQL Server, Entity Framework, Windows Communication Framework (WCF), C#, Microsoft Visual Studio, Unit Testing, REST, LINQ, Scrum, JavaScript, Object-oriented Programming (OOP), HTML, C#.NET, Java, SQL, APIs, Source Code Review, Code Review, Task Analysis, Visual Studio, Back-end, SOLID Principles, Dependency Injection, Inversion of Control, Functional Programming, Object-oriented Design (OOD), SQL Server Management Studio, Refactoring, Design Patterns, Debugging, Mathematics, UI, UX, Front-end, MySQL, RESTful APIs, Web API

Experience

  • Boostlingo Platform
    https://boostlingo.com

    The Boostlingo platform unifies all the technology and workflow components necessary to support the management and coordination of customers interpretation related tasks, including on-site interpreter appointment scheduling, the management of on-demand and scheduled over-the-phone and video remote interpreting sessions, complete with all the ancillary business analytics and business administrative tools that customers need to get the job done.

  • Sogotrade.com Trading Platform
    http://sogotrade.com/

    Sogotrade is a large-scale distributed platform for stock and options trading. It includes web and desktop client terminals and a set of powerful market research tools to help customers achieve their investing and trading goals.

  • ETNA Trader
    https://www.etnasoft.com/etna-trader/

    ETNA Trader is a flagship all-in-one white label trading platform for online broker-dealers. It features a front office and back office and integrates with a variety of third-party services and exchanges.

  • ASPro
    https://www.tuvsud.com/en

    An enterprise software system for TÜV SÜD, a service corporation focusing on testing and certification in the industrial sector.

    The system consists of two major parts: a desktop workstation for the technical inspection of cars and other vehicles and a web application for organizing drivers' license exams, surrounded by a set of back-end services and external systems.

  • Infor Learning Management System

    Infor Learning Management System is an enterprise SaaS solution for creating, delivering, and reporting on learning throughout customers' internal and extended organization. The goal of this solution is to replace complex processes, workflows, and systems with sophisticated yet intuitive technology.

  • PolyGen
    https://github.com/sergey-kolodiy/PolyGen

    PolyGen is an open-source Roslyn-based code generator that produces an object-relational mapping layer using Entity Framework, REST API using ASP.NET Core Web API, and a user interface for a user-defined domain model.

  • Microsoft Certified Professional
    https://mcp.microsoft.com/Anonymous/Transcript/Validate

    Microsoft Certified Professional (MCP) certification validates IT professional and developer technical expertise through rigorous, industry-proven, and industry-recognized exams. MCP exams cover a wide range of Microsoft products, technologies, and solutions.

    To validate the certification, use the following information:
    Transcript ID: 1166968
    Access Code: F4163941

  • Functional Programming Principles in Scala
    https://www.coursera.org/verify/TN47UQ4G6A

    The Functional Programming Principles in Scala course introduces the cornerstones of functional programming using the Scala programming language. In this course, students discover the elements of the functional programming style and learn how to apply them usefully in their daily programming tasks, such as modeling business domains or implementing business logic.

  • Stack Overflow — Top 7% Overall
    http://stackoverflow.com/users/3478087

    Stack Overflow is a place where developers and technologists go to gain and share knowledge.
    Seventy-seven answers were given.
    Active in C#, .NET, ASP.NET, ASP.NET Web API, Unit testing, and Entity­ Framework. Top 7% overall.

  • Unit Tests, How to Write Testable Code, and Why It Matters (Publication)
    In this article, I will show that unit testing itself is quite easy; the real problems that complicate unit testing, and introduce expensive complexity, are a result of poorly-designed, untestable code. We will discuss what makes code hard to test, which anti-patterns and bad practices we should avoid to improve testability, and what other benefits we can achieve by writing testable code. We will see that writing testable code is not just about making testing less troublesome, but about making the code itself more robust, and easier to maintain.
  • Toptal Mentor
    Sergey is a mentor in the Toptal Global Mentor’s Program. This program is a partnership between Toptal and General Assembly to provide high quality mentorship for students from minority and low income backgrounds who are looking to begin their careers as professional software engineers. Sergey shows commitment to diversity in tech by mentoring a General Assembly student every week for a year, covering everything from coding tips and tricks to advice on making it in the industry.

Skills

  • Languages

    Markdown, C#, C#.NET, T-SQL, HTML, JavaScript, SQL, Java, Scala
  • Frameworks

    .NET Core, ASP.NET Core, .NET, ASP.NET Web API, ASP.NET MVC, Entity Framework Core, Entity, NUnit, AngularJS, ASP.NET, ASP.NET Identity, Windows Communication Framework (WCF), OAuth 2
  • Libraries/APIs

    LINQ, Web API, REST APIs, Moq, Entity Framework, SignalR, PubNub, SendGrid API, Twilio API, D3.js, Telegram Bot API
  • Tools

    Visual Studio, Microsoft Visual Studio, Azure DevOps Services, Git, Fiddler, Roslyn, Chrome Developer Tools, MSTest, SendGrid, Postman, Trello, Jira, Twilio Programmable Video, Zoom
  • Paradigms

    REST, Unit Testing, Object-oriented Programming (OOP), Dependency Injection, Object-oriented Design (OOD), Inversion of Control, Refactoring, Scrum, Microservices Architecture, Microservices, Functional Programming, Metaprogramming, Design Patterns, Azure DevOps, ETL, Test-driven Development (TDD), Agile Software Development
  • Other

    SOLID Principles, .NET 6, APIs, Task Analysis, Back-end, Debugging, RESTful APIs, Code Auditing, Single-page Applications (SPA), Identity Server, Algorithmic Trading, Microsoft Azure, Source Code Review, Code Review, CI/CD Pipelines, Architecture, Mathematics, Software Architecture, OAuth, Performance Analysis, Microsoft Data Transformation Services (now SSIS), Domain-driven Design (DDD), Trading, Stock Price Analysis, UI, UX, Front-end
  • Platforms

    Azure, Twilio, Windows, Visual Studio Code, Arduino, Web
  • Storage

    SQL Server Management Studio, Microsoft SQL Server, Redis, Data Integration, SQL Server Integration Services (SSIS), MySQL

Education

  • Bachelor's Degree in Information Systems and Technologies
    2005 - 2010
    Voronezh Institute of High Technologies - Voronezh, Russia

Certifications

  • Microsoft Certified Professional
    SEPTEMBER 2015 - PRESENT
    Microsoft
  • Microsoft Specialist: Programming in C#
    SEPTEMBER 2015 - PRESENT
    Microsoft
  • Functional Programming Principles in Scala
    JULY 2014 - PRESENT
    Coursera

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