Casey McQuillan, Developer in Ventura, CA, United States
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Casey McQuillan

Verified Expert  in Engineering

Software Developer

Ventura, CA, United States
Toptal Member Since
April 25, 2019

Casey has over six years of full-stack web development experience with .NET technologies. He's developed large-scale food-safety certification systems for ServSafe which serves millions of users annually. Casey also has experience in all aspects of creating SaaS applications and would love to work with you on your next product.


Quill Technologies, LLC
Amazon Web Services (AWS), MySQL, PHP, Microsoft Azure, .NET Core, ASP.NET...
National Restaurant Association
Visual Basic for Applications (VBA), Oracle Service Bus (OSB), Apache Storm...




Preferred Environment

Docker, Visual Studio, Windows

The most amazing...

...feeling was when I completed a digital transformation project for a training company and saw that they literally saved US $1 million per year in paper costs.

Work Experience

Principal Software Engineer | CEO

2016 - PRESENT
Quill Technologies, LLC
  • Designed and developed Vendorsync SaaS accounting productivity app with Quickbooks Desktop integration. Reduced customer data entry burden by over 50%.
  • Refactored GCODE rendering engine for a 3D printer to extract logic from base application. This allowed the client to establish additional product lines.
  • Designed and developed Public API for healthcare company enabling partner integrations to meet state government contract requirements.
  • Was a sole principal of a software development firm servicing clients in accounting, eCommerce, and online learning verticals. I worked on consultation, development, and implementation deliverables for the entire Software Development Life Cycle.
  • Conducted source code and project audits to guide technology strategy. Deliverables resulted in immediate cost savings and measurable technology improvements for clients.
  • Delivered features in the online orders portal for robotic handwriting startup. Enhanced letter design, templating, font ligatures, new handwriting style implementations, and customer onboarding.
  • Created a data integration system for managing over 50 distinct membership data imports. Involved multiple CRM integrations including YourMembership, iMIS, and WebLinks.
  • Delivered prototype Xamarin mobile gift card wallet application for Android and iOS.
  • Consulted on and implemented eCommerce analytics and SEO best practices for multiple clients.
  • Delivered LMS implementation using WordPress, WooCommerce, and LearnDash.
Technologies: Amazon Web Services (AWS), MySQL, PHP, Microsoft Azure, .NET Core, ASP.NET, WordPress, Security, Azure Service Bus, Continuous Integration (CI), Docker, IdentityServer 4, OpenID Connect (OIDC), ASP.NET Core, Blazor, JavaScript, T-SQL (Transact-SQL), C#, Azure DevOps, Azure App Service, OAuth 2, Angular CLI, Visual Studio 2019, Continuous Delivery (CD), Identity Server, Azure SQL, SQL Server 2016, Azure

Developer Analyst II

2010 - 2016
National Restaurant Association
  • Designed, developed, and maintained the document generation system for the ServSafe e-Certs module. The project reduced printing and shipping costs by over US $1,000,000 per year.
  • Delivered Continuous Delivery/Continuous Integration pipelines using Powershell and Microsoft Release Management. Reduced deployment time for applications from hours to minutes.
  • Created application for streamlining NRA committee selections using Visual Basic and MS Access which reduced process flow from multiple weeks to six hours.
  • Managed external vendor relationships to migrate the proxy voting process from paper to online platform, saving paper mailing costs, and reducing legal exposure.
  • Designed and implemented back-end WCF services to drive online learning, eCommerce, assessment, and food safety certification applications (
  • Created a proprietary library for running C# code on Apache Storm. This library pre-dated publicly available SDKs by approximately six months (StormSharp).
  • Wrote independently Python module to scrape undocumented legacy ColdFusion and generate documentation from file metadata.
Technologies: Visual Basic for Applications (VBA), Oracle Service Bus (OSB), Apache Storm, Microsoft SQL Server, Windows Presentation Foundation (WPF), ASP.NET, SQL, iMIS, Security, Continuous Integration (CI), OpenID Connect (OIDC), JavaScript, T-SQL (Transact-SQL), C#, OAuth 2, Visual Studio 2019, Continuous Delivery (CD), Kentico, Identity Server, SQL Server 2016, Azure


I Implemented a proprietary C# library to interface .NET
technologies with the Apache Storm stream-processing tool.

The company I was working with was exclusively a .NET shop and had decided to migrate a substantial piece of infrastructure to Apache Storm.

Storm was a tool that performed best when the code is in its native Java, but it had a multilanguage interface capable of executing code in any language which could provide an adapter library. At the time, HD Insight was still six months away from announcing their library providing .NET support for Storm.

Using the documentation on Storm's multilanguage specification and a couple of weeks, I was able to create a feature-complete library which could act as a C# interface for running Storm bolts/spouts and managing Storm topology definitions.

I implemented a simple SMTP server in C# to aid in the development and testing of applications which send emails. This project's eventual goal is to implement RFC 5321 and RFC 5322 and become a fully standards-compliant SMTP server and relay. is an open tool for web developers doing local development against OAuth services with strict redirect rules. For security purposes, these OAuth services require developers to specify a redirect where they will send users after a successful OAuth handshake. Frequently there are arbitrary rules imposed on these URIs that make it challenging to develop your integration locally (such as being only HTTP/HTTPS, not allowing any localhosts, and so on).

This tool will accept any URL after "" and will forward all path, query, and hash URL parameters to the developer's localhost.

I built the tool using TypeScript, HTML, CSS, and hosted it on my personal Kubernetes cluster. I made it to solve a problem with an OAuth provider I was building against and decided to release it openly for anyone who needs it.
2004 - 2008

Bachelor's Degree in Political Science

University of California, Davis - Davis, CA, USA


MCSA: Web Applications — Certified 2019



Cybersecurity Specialization

University of Maryland, College Park via Coursera


MediatR, AutoMapper, jQuery, Node.js


Azure App Service, Angular CLI, Visual Studio 2019, Kentico, Visual Studio, Apache Storm, Azure Key Vault


ASP.NET Core, ASP.NET, .NET Core, .NET, Blazor, IdentityServer 4, ASP.NET Core 2, Angular, Angular Material, ASP.NET Web Forms, OAuth 2, Windows PowerShell, Bootstrap, Windows Presentation Foundation (WPF)


iMIS, Docker, Kubernetes, Xamarin, Windows, Azure, Visual Studio Code (VS Code), Amazon Web Services (AWS), Linux, WordPress, Umbraco


HTML, Java, C#, T-SQL (Transact-SQL), JavaScript, TypeScript, HTML5, CSS, XAML, SQL, Visual Basic for Applications (VBA), PHP


SQL Server 2016, Azure SQL, Azure Blobs, Microsoft SQL Server, MySQL


Azure DevOps, Object-oriented Programming (OOP), Test-driven Development (TDD), Continuous Integration (CI), Continuous Delivery (CD)


OpenID Connect (OIDC), Windows Communication Foundation (WCF), Azure Service Bus, Security, Identity Server, Xamarin.Forms, Oracle Service Bus (OSB), Microsoft Azure

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