Orest Khrapko, Developer in Warrington Township, PA, United States
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Orest Khrapko

Verified Expert  in Engineering

Software Developer

Warrington Township, PA, United States
Toptal Member Since
October 14, 2014

Orest is a highly skilled senior developer/architect with extensive development experience in system design and implementation using .NET stack: C#, .NET Core, MVC, Web API, SQL, and Entity Framework. He is passionate about JavaScript and related technologies, such as Angular, Vue.js, Ionic, jQuery, or Node.js. He has built many complex world-class products from start to finish, making every project he works on a success story.


Microsoft SQL Server, .NET Core, ASP.NET MVC, JavaScript, C#...
Advertising Specialty Institute-ASI
Endeca, Elasticsearch, MongoDB, MySQL, Microsoft SQL Server, RequireJS...
SAML, Log4Net, StructureMap, Ninject, Entity Framework, RequireJS...




Preferred Environment

Azure, .NET Core, Web API, Ionic, SQL, C#, JavaScript, Angular, Amazon Web Services (AWS), React

The most amazing...

...things I've designed and developed are complex SaaS applications.

Work Experience

Senior Enterprise Architect

2014 - PRESENT
  • Analyzed, upgraded, consolidated, and mapped enterprise applications, mobile strategy, and development.
  • Designed and implemented a SaaS to support a new line of business in credit card origination. The main modules included credit bureau integration, identity verification, multiple pricing model support, multiple line assignment model support, and more.
  • Designed and developed a multi-tenant mobile application.
Technologies: Microsoft SQL Server, .NET Core, ASP.NET MVC, JavaScript, C#, Mobile Development, Ionic, Angular, SQL, Bootstrap, Git, Azure, Twilio, Mobile, Mobile Applications, Amazon Web Services (AWS), REST APIs, Jira, TypeScript

Senior Enterprise Architect

2012 - 2014
Advertising Specialty Institute-ASI
  • Redesigned a supplier’s product update flow that reduced product update propagation to all downstream systems from 24-48 hours to near real-time. Flow simplification allowed for retiring around 15 auxiliary applications.
  • Architected a new service-oriented framework built with the latest technologies, including MVC, HTML5, ASP.NET Web API, Entity Framework, Knockout.js, RabbitMQ, and RequireJS. The new framework improved time to market, productivity, and performance.
  • Designed and architected reviews, recommendations, and approval for all changes in the development sprint. Assessed proposed application changes and came up with the most optimized system/change implementation and reusability method.
  • Integrated and designed applications regarding an ASI identity provider using an OAuth2 protocol.
  • Helped set up a continuous integration server using Jenkins.
Technologies: Endeca, Elasticsearch, MongoDB, MySQL, Microsoft SQL Server, RequireJS, Knockout (Knockout.js), AngularJS, jQuery, Ajax, REST, HTML5, Web API, ASP.NET Web Forms, ASP.NET MVC 4, ASP.NET, C#, SQL, JavaScript, Angular, Bootstrap, Git, Azure, REST APIs


2009 - 2012
  • Created a proprietary application framework that addressed the modern UX, security, performance, flexibility, extensibility, scalability, and content management-related issues needed to support users and enable full cross-product integration.
  • Integrated Oracle CRM single sign-on using SAML and Oracle web services for customer information integration.
  • Oversaw the architecture of migration to distributed version control (Git).
  • Acted as technical lead and architect on an ESP websites project. This product allows distributors to have a fully functioning eCommerce site in a few easy steps.
  • Improved time-to-market for new products with the framework by 40% through re-engineering and unifying security, UI rendering mechanisms, and middle-tier object repositories, and utilized a modular approach to development for greater code reusability.
Technologies: SAML, Log4Net, StructureMap, Ninject, Entity Framework, RequireJS, Knockout (Knockout.js), AngularJS, jQuery, Ajax, REST, HTML5, Web API, ASP.NET MVC 4, ASP.NET Web Forms, ASP.NET, C#, SQL, JavaScript, Bootstrap, Git, RabbitMQ, .NET Core, Architecture, Web Architecture, REST APIs, Jira

Technical Lead

2007 - 2009
Advanta Business Services
  • Worked on infrastructure design and implementation of Advanta’s online originations and underwriting systems using Provenir, web services, Interwoven, and ASP.NET.
  • Designed and did end-to-end setup and implementation of Advanta’s underwriting flow using Provenir. This includes: infrastructure setup with MQSeries, Tomcat, LDAP, JRE, and more; Provenir software configuration with different adapters and third party hooks like credit bureau integration, address validation services, identity verification services; and integration with other systems in the Enterprise-like web, back office, and servicing platforms.
  • Coded underwriting workflows, scripts, and adapters for Provenir.
  • Designed and developed various web services (SOAP) and websites using ASP.NET, ASP, ColdFusion and Interwoven (Java, XSLT, XSL).
  • Maintained the Interwoven controller layer using Java and web services.
Technologies: XSL, XSLT, Apache Tomcat, Java, IBM MQ, MSMQ, Web Services, ASP.NET, VB.NET, C#, SQL, JavaScript, Bootstrap, Git

Senior Developer

2001 - 2007
Advanta Business Services
  • Maintained and developed a web-based customer service interface for a credit decision application.
  • Developed various web services and websites.
  • Worked with a team to convert advanta.com to use the Interwoven CMS system.
  • Developed various applications and support utilities using VB.NET 2.0, 1.1, and VB6.
  • Modified, maintained, and upgraded proprietary credit decision systems from Provenir. Created workflows, scripts, and adapters using JavaScript and VBScript.
  • Upgraded applications and systems from Sybase to Oracle.
Technologies: Content Management Systems (CMS), WebSphere MQ, MSMQ, Ajax, JavaScript, XML, HTML, Adobe ColdFusion, Active Server Pages (ASP), ASP.NET, SQL, Git

Software Developer

1998 - 2001
Advanta National Bank
  • Developed web applications using Oracle web agent packages.
  • Created an online banking site for Advanta Bank Corp. using ASP.
  • Developed multiple reports using an SQR reporting tool.
  • Performed Oracle DBA tasks such as backups and software upgrades.
  • Implemented Y2K modifications on existing financial software.
Technologies: Visual Basic 6 (VB6), SQR, Active Server Pages (ASP), Oracle DBA, SQL, JavaScript
1998 - 2006

Bachelor of Science Degree in Computer Science

Drexel University - Philadelphia

1991 - 1993

Associate of Engineering Degree in Mechanical Engineering

Lutsk State Tech University - Lutsk, Ukraine


AWS Certified Developer Associate

Amazon Web Services


AWS Certified Cloud Practitioner

Amazon Web Services


Stripe, RequireJS, Underscore.js, Vue, Entity Framework, REST APIs, AMQP, Sammy.js, React, Web API, jQuery, Log4Net


TFS, Git, StructureMap, Jira, Jenkins, Navicat, Bower, Webpack, Ninject, IBM MQ, Apache Tomcat, Adobe ColdFusion, Eclipse IDE, Babel, RabbitMQ, Amazon Simple Queue Service (SQS)


Angular, ASP.NET MVC, Ionic, Bootstrap, .NET Core, Kendo UI, Knockout (Knockout.js), JavaScript MVC, ASP.NET, ASP.NET MVC 4, ASP.NET Web Forms, AngularJS, .NET


SQL, HTML5, C#, JavaScript, CSS, HTML, TypeScript, PHP, SAML, VB.NET, XSLT, XSL, Active Server Pages (ASP), XML, SQR, Visual Basic 6 (VB6), Java


Twilio, Azure, Mobile, Oracle, Amazon Web Services (AWS), Endeca, WebSphere MQ, LAMP, Linux, Amazon EC2, AWS Elastic Beanstalk


HTML5 Web Storage, JSON, Elasticsearch, Memcached, Membase, Redis, MySQL, Microsoft SQL Server, Oracle DBA, MongoDB, Amazon S3 (AWS S3)


REST, Mobile Development, Web Architecture


Software Development, Front-end, Mobile Applications, Ajax, Web Services, MSMQ, Content Management Systems (CMS), Computer Science, Mechanical Engineering, Architecture, Amazon RDS

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