Andy Gill, Developer in Palm Beach Gardens, FL, United States
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Andy Gill

Bio

Andy, a full-stack developer with 20 years of software experience, specializes in the .NET stack, covering requirements gathering, SQL database design, and development across web, Windows, and mobile platforms. Skilled in system monitoring, his strengths include .NET MAUI cross-platform apps, conversational bots for Amazon Alexa and Google Home, and full .NET stack for web or Windows. Andy is passionate about improving client experiences through problem-solving.

Portfolio

Freelance
C#.NET, .NET 5, SQL, Telerik Kendo UI, Xamarin.Forms, Amazon Alexa, Google Home...
JBZ Bookkeeping LLC
.NET, SOAP APIs, QuickBooks Online, Amazon Web Services (AWS), C#.NET...
Protos Security
Xamarin, Xamarin Studio, C#.NET, Mobile Development, iOS, Cross-platform...

Experience

  • .NET - 20 years
  • C#.NET - 20 years
  • SQL - 20 years
  • Web Architecture - 10 years
  • Mobile Development - 6 years
  • Cross-platform - 6 years
  • Angular - 5 years
  • .NET MAUI - 4 years

Preferred Environment

.NET, AI Chatbots, DevOps, AI Integration, APIs, Azure, iOS, Android, Angular, Cross-platform

The most amazing...

...product I've built is BackOfficeScheduler, an app suite of two iOS and Android apps, a bot accessible via Alexa and text messaging, and a .NET core website.

Work Experience

Senior Full-stack Developer

2019 - PRESENT
Freelance
  • Designed and researched requirements for the B2B application site to enable businesses to manage their employee and customer schedules and appointments.
  • Integrated a PayPal and Stripe payment API to allow organizations and their customers to make payments.
  • Created a Microsoft Framework bot accessible via Google Home, Alexa, and text messaging to allow customers to manage their appointments.
Technologies: C#.NET, .NET 5, SQL, Telerik Kendo UI, Xamarin.Forms, Amazon Alexa, Google Home, Microsoft Bot Framework, Mobile Development, iOS, Cross-platform, Architecture, Android, .NET MAUI, Full-stack, Graphs, Dashboards, Software Design Patterns, Agile Software Development, Web Architecture, HTML, Web Development, CSS, HTML5, REST, OData, Texting, Blazor, API Integration, ASP.NET Razor, Zapier, APIs, REST APIs, C#, Payment APIs, JavaScript, Payment Processing, jQuery, PayPal, PayPal API, Stripe, Stripe API, Generative Pre-trained Transformers (GPT), Artificial Intelligence (AI), Algorithmic Trading, Facebook API, Google API, Microsoft SQL Server, MongoDB, Technical Architecture, Amazon Web Services (AWS), Project Estimation, Project Management, IT Project Management, User Interface (UI), User Experience (UX), Node.js, React, Automation, Algorithms, Azure, Microservices, .NET Core, DevOps, Cloud Services, CI/CD Pipelines, Integration, XML Web Services, XSD, XML, Windows UI, Back-end, Intuit QuickBooks, QuickBooks API, Data Analysis, Data Engineering, Excel 365, Data Scraping, Facebook Authentication, Facebook, IIS SQL Server, Office 365, Single Sign-on (SSO), ASP.NET Core, SQL Server 2016, Entity Framework, Azure DevOps, IIS, RTMP, Streaming, Broadcasting, Authorization, User Authentication, Authentication, Software Architecture, Mobile App Development, Full-stack Development, Google Maps, Software Documentation, Business Analysis, Python, AI Integration, Development, MVP Design, SaaS, Subscriptions, Agile, Technical Leadership, Database Architecture, Data Structures, TypeScript, Windows, Tailwind CSS, Desktop App Development, Front-end, WebApp, Sass, Git, ETL, Startups, Distributed Systems, Next.js, Mobile, React Native, Instant Messaging, Large Language Models (LLMs), Web Forms, Xamarin, Minimum Viable Product (MVP), Cross-platform App Development, Offline-first Development, Cloud, Inventory Management, Offline Data Synchronization, Point of Sale, Solution Architecture, Cloud Architecture, Databases, Deployment, OpenAI, Gmail API, App Store, Google Play Store, Mobile Apps, WebView, Flutter, HTTPS, JSON, Webhooks, Machine Learning, YouTube API, API Databases, Database Design, Scalable Web Services, Software System Design & Configuration, Testing, Classic ASP, Azure SQL, Android App Development, Leadership, Azure App Service, Bootstrap, Razor Pages, .NET 6, GitHub, FTP, SFTP, VPN, Web Server (IIS), Blazor WebAssembly, Back-end Development, Software as a Service (SaaS), ASP.NET MVC, Telerik, Software Design, Technical Requirements, Healthcare, Bots, ChatGPT, Slack, Payment Gateways, .NET 8, JSON Web Tokens (JWT), Apache Kafka, RabbitMQ, RESTFul APIs, Communication, Critical Thinking, Time Management, WebSockets, NinjaTrader, Angular, Scrum, Razor, Generative Artificial Intelligence (GenAI), Prompt Engineering, eCommerce, Customer Relationship Management (CRM), Intercom, Intercom API, SMS, Kubernetes, OpenAI API, Agentic Frameworks, AI Agents, AI Chatbots, QuickBooks Online, CSV Export, SOAP APIs, Event-driven Programming, Coding, Microsoft Excel, Software Development, Excel VBA, Data Migration, Security, Twilio, Software, Mobile UI, Microsoft Copilot, CSV, Azure Active Directory B2C (ADB2C), Customer Identity and Access Management (CIAM), Microsoft Entra External ID

.NET Developer

2025 - 2025
JBZ Bookkeeping LLC
  • Integrated Praxedo CRM work orders with QuickBooks API to create invoices.
  • Helped develop business requirements with users and management.
  • Provided logging and deployment support to help non-technical users manage the application.
Technologies: .NET, SOAP APIs, QuickBooks Online, Amazon Web Services (AWS), C#.NET, CSV Export, REST APIs, Software, Mobile UI, Microsoft Copilot, CSV, Artificial Intelligence (AI), Azure Active Directory B2C (ADB2C), Customer Identity and Access Management (CIAM)

Mobile Developer

2022 - 2024
Protos Security
  • Developed a Xamarin app to augment and eventually replace the mobile website to manage guard activities.
  • Researched the progress of .NET MAUI replacing Xamarin, and updated management to help decide on an appropriate time to switch to MAUI.
  • Rewrote the Xamarin app to .NET MAUI Blazor Hybrid to take advantage of sharing work between the website and native apps using a junior developer to reduce costs and speed up timelines.
Technologies: Xamarin, Xamarin Studio, C#.NET, Mobile Development, iOS, Cross-platform, Architecture, Android, Full-stack, Charts, Software Design Patterns, Agile Software Development, Web Architecture, HTML, Web Development, CSS, HTML5, REST, OData, Blazor, API Integration, ASP.NET Razor, APIs, REST APIs, C#, JavaScript, jQuery, Facebook API, Google API, Microsoft SQL Server, Technical Architecture, Amazon Web Services (AWS), Project Estimation, Project Management, IT Project Management, User Interface (UI), User Experience (UX), Algorithms, Azure, Microservices, .NET Core, DevOps, Cloud Services, CI/CD Pipelines, Kanban, Integration, XML Web Services, XSD, XML, Back-end, Data Analysis, Data Engineering, Facebook Authentication, Facebook, IIS SQL Server, ASP.NET Core, SQL Server 2016, Entity Framework, Azure DevOps, IIS, Real-time Messaging Protocol (RTMP), Authorization, User Authentication, Authentication, Software Architecture, Mobile App Development, Full-stack Development, Google Maps, Software Documentation, Business Analysis, AI Integration, Development, MVP Design, SaaS, Agile, Technical Leadership, Database Architecture, Data Structures, TypeScript, Windows, Discord, Front-end, WebApp, Sass, Git, ETL, Startups, Distributed Systems, Mobile, MySQL, Web Forms, Minimum Viable Product (MVP), Cross-platform App Development, Offline-first Development, Cloud, Offline Data Synchronization, Point of Sale, Solution Architecture, Cloud Architecture, Databases, Deployment, Gmail API, App Store, Google Play Store, Mobile Apps, WebView, HTTPS, JSON, Webhooks, API Databases, Database Design, Scalable Web Services, Software System Design & Configuration, Testing, Azure SQL, Android App Development, Leadership, Azure App Service, Bootstrap, Razor Pages, .NET 6, GitHub, FTP, SFTP, VPN, Web Server (IIS), Blazor WebAssembly, Back-end Development, Software as a Service (SaaS), ASP.NET MVC, Telerik, Software Design, Technical Requirements, Bots, Slack, Discord Bots, Payment Gateways, .NET 8, JSON Web Tokens (JWT), OAuth, RabbitMQ, RESTFul APIs, Communication, Critical Thinking, Time Management, WebSockets, Angular, Scrum, Test-driven Development (TDD), Razor, Prompt Engineering, Customer Relationship Management (CRM), Intercom, Intercom API, SMS, Kubernetes, OpenAI API, Agentic Frameworks, AI Agents, AI Chatbots, CSV Export, SOAP APIs, OpenAI GPT-4 API, Event-driven Programming, Coding, Software Development, Data Migration, QuickBooks Desktop, Security, Twilio, Software, Mobile UI, CSV, Auth0, Customer Identity and Access Management (CIAM)

Senior Full-stack Developer

2012 - 2021
AMAG Technology
  • Maintained and upgraded a web app from Windows Forms through .NET MVC and eventually .NET Core with an Angular front end.
  • Created, published, and maintained iOS and Android apps via Xamarin Forms to monitor the positions and activities of guards and deploy them as needed.
  • Mentored junior developers and the offshore team to increase productivity.
Technologies: .NET, Angular, Xamarin.Forms, SQL, Windows Forms (WinForms), Mobile Development, iOS, Cross-platform, Architecture, Android, Full-stack, Graphs, Charts, Dashboards, Software Design Patterns, Agile Software Development, Web Architecture, HTML, Web Development, CSS, HTML5, REST, OData, API Integration, ASP.NET Web Forms, APIs, .NET 4, REST APIs, C#, JavaScript, PCI, jQuery, Facebook API, Google API, Microsoft SQL Server, Technical Architecture, Project Estimation, Project Management, User Interface (UI), User Experience (UX), Automation, Algorithms, Azure, Microservices, .NET Core, DevOps, Cloud Services, CI/CD Pipelines, Kanban, Integration, XML Web Services, XSD, XML, Back-end, Data Analysis, Data Engineering, Facebook Authentication, Facebook, Office 365 API, IIS SQL Server, Office 365, Single Sign-on (SSO), ASP.NET Core, SQL Server 2016, Entity Framework, Azure DevOps, IIS, Kotlin, User Authentication, Authentication, Visual Basic, VB.NET, Software Architecture, Mobile App Development, Full-stack Development, Google Maps, Networking, Software Documentation, Business Analysis, Content Management Systems (CMS), Development, IT Management, SaaS, Agile, Technical Leadership, Database Architecture, Data Structures, Windows, Tailwind CSS, Desktop App Development, Front-end, WebApp, Sass, Git, ETL, Startups, Distributed Systems, Next.js, PostgreSQL, Mobile, MySQL, Web Forms, Xamarin, Minimum Viable Product (MVP), Cross-platform App Development, Cloud, Offline Data Synchronization, Solution Architecture, Cloud Architecture, Databases, Deployment, Gmail API, App Store, Google Play Store, Mobile Apps, WebView, HTTPS, JSON, Webhooks, API Databases, Database Design, Scalable Web Services, Software System Design & Configuration, Testing, Azure SQL, Android App Development, Leadership, Azure App Service, Bootstrap, Razor Pages, .NET 6, GitHub, SFTP, VPN, Web Server (IIS), Blazor WebAssembly, Back-end Development, Software as a Service (SaaS), ASP.NET MVC, Telerik, Universal Windows Platform (UWP), Software Design, Technical Requirements, HIPAA Compliance, Payment Gateways, .NET 8, JSON Web Tokens (JWT), OAuth, RESTFul APIs, Communication, Critical Thinking, Time Management, WebSockets, Scrum, CSV Export, SOAP APIs, Event-driven Programming, Coding, Microsoft Excel, Software Development, Workbooks API, Spreadsheet Automation, Excel VBA, Data Migration, Security, Twilio, Software, Mobile UI, CSV, Auth0, Okta

Senior Full-stack Engineer

2009 - 2012
Reverse Mortgage Solutions
  • Oversaw a Windows Forms application to help property managers maintain properties obtained via foreclosure.
  • Developed a Windows Workflow Foundation system to generate reports that were previously created manually.
  • Mentored new developers to speed up the development of the internal company website to track use and progress of the Windows Forms app.
Technologies: Windows Forms (WinForms), SQL, ASP.NET, Windows Workflow Foundation, Architecture, Full-stack, Graphs, Charts, Dashboards, Software Design Patterns, Agile Software Development, Web Architecture, HTML, Web Development, CSS, HTML5, REST, OData, API Integration, ASP.NET Web Forms, APIs, .NET 4, REST APIs, C#, WCF Web Services, JavaScript, PCI, C++, Facebook API, Google API, Microsoft SQL Server, Technical Architecture, Project Estimation, Project Management, User Interface (UI), User Experience (UX), Fintech, Automation, Algorithms, DevOps, CI/CD Pipelines, XML Web Services, XSD, XML, Windows UI, Back-end, Data Analysis, Data Engineering, Facebook Authentication, Facebook, IIS SQL Server, ASP.NET Core, SQL Server 2016, Entity Framework, IIS, User Authentication, Authentication, Software Architecture, Full-stack Development, Networking, C, Software Documentation, Content Management Systems (CMS), Development, IT Management, Agile, Database Architecture, Data Structures, Microsoft Access, Windows, Desktop App Development, Front-end, WebApp, Sass, Git, ETL, PostgreSQL, MySQL, React Native, Web Forms, Offline Data Synchronization, Solution Architecture, Databases, Deployment, API Databases, Database Design, Scalable Web Services, Software System Design & Configuration, Testing, Leadership, Bootstrap, GitHub, Web Server (IIS), Back-end Development, Software as a Service (SaaS), ASP.NET MVC, Telerik, Universal Windows Platform (UWP), Software Design, Technical Requirements, Communication, Critical Thinking, Time Management, SOAP APIs, Event-driven Programming, Coding, Software Development, Security, CSV, Okta

Senior Full-stack Developer

2004 - 2009
Bankrate.com
  • Managed the offshore development team to accomplish project goals.
  • Redesigned the website from classic ASP to the new .NET Web Forms project.
  • Initiated the addition of external-facing API to allow customers to offload some of the work that Bankrate was doing.
Technologies: ASP.NET, SQL, JavaScript, Agile Software Development, Architecture, Full-stack, Graphs, Charts, Software Design Patterns, Web Architecture, HTML, Web Development, CSS, REST, API Integration, ASP.NET Web Forms, APIs, .NET 4, REST APIs, C#, WCF Web Services, C++, Facebook API, Google API, Microsoft SQL Server, Project Estimation, User Interface (UI), User Experience (UX), Fintech, Algorithms, DevOps, XML Web Services, XSD, XML, Windows UI, Back-end, Facebook Authentication, Facebook, Office 365 API, IIS SQL Server, ASP.NET Core, SQL Server 2016, Entity Framework, IIS, User Authentication, Authentication, Full-stack Development, Networking, Software Documentation, Development, Microsoft Access, Windows, Desktop App Development, Front-end, ETL, MySQL, Web Forms, Databases, Deployment, API Databases, Database Design, Scalable Web Services, Software System Design & Configuration, Testing, Web Server (IIS), Software Design, Communication, Critical Thinking, Time Management, Coding, Software Development, Security

Experience

BackOfficeScheduler

http://backofficescheduler.com
I built this app suite featuring a pair of iOS and Android apps, a bot accessible via Alexa and text messaging, and a .NET core website. I've upgraded it from .NET MVC to .NET Core 2 and 3 and finally to .NET 5, and successfully published the apps and the Alexa bot. I'm rewriting the web and apps to use Blazor (hosted by MAUI Blazor Hybrid) to increase code sharing and speed up development time for a hard launch after beta testing with a few key users.

MAUI Blazor Hybrid Website and App to Manage Guard Services

https://apps.apple.com/us/app/protos-mobile/id1610768348
A Blazor website hosted natively on iOS and Android via MAUI Blazor Hybrid to let guards log in and out of shifts, report incidents, receive pertinent alerts, and conduct building tours by scanning NFC tags, barcodes, or QR codes. It is based on an existing responsive web app but explicitly designed for mobile and equally capable on a web browser or mobile phone except for platform-specific functions like NFC tag scanning.

Video Streaming App and Website

A .NET-based website and accompanying ASP.NET Core app to allow users to stream live video for sports events, including labeling participants, keeping score, and allowing users to tag clips as highlights with the tag type and the player. Other users following that player can watch the games live or reply and view the accumulated highlights for that player or game on the website or app.

Education

2000 - 2004

Bachelor's Degree in Computer Information Systems

Palm Beach Atlantic University - West Palm Beach, Florida, USA

Skills

Libraries/APIs

Windows Forms (WinForms), REST APIs, jQuery, Facebook API, Google API, Facebook Authentication, Entity Framework, Gmail API, OpenAI API, SOAP APIs, PayPal API, Stripe, Stripe API, QuickBooks API, Google Maps, YouTube API, Intercom API, Workbooks API, Node.js, React, Office 365 API

Tools

Microsoft Access, Git, WebView, Azure App Service, Microsoft Excel, Microsoft Copilot, Zapier, GitHub, VPN, ChatGPT, Slack, RabbitMQ, Auth0, Azure Active Directory B2C (ADB2C), Azure OpenAI Service, NinjaTrader

Languages

SQL, C#.NET, JavaScript, HTML, HTML5, CSS, ASP.NET Razor, C#, XSD, XML, Visual Basic, VB.NET, Sass, C, TypeScript, Excel VBA, C++, Kotlin, Active Server Pages (ASP), Python

Frameworks

.NET, .NET 5, Telerik Kendo UI, ASP.NET, .NET MAUI, Blazor, ASP.NET Web Forms, .NET 4, .NET Core, ASP.NET Core, WebApp, Bootstrap, Razor Pages, .NET 6, Blazor WebAssembly, ASP.NET MVC, .NET 8, JSON Web Tokens (JWT), Razor, Agentic Frameworks, Angular, Classic ASP, Flutter, Windows Workflow Foundation, Tailwind CSS, Next.js, React Native

Paradigms

Agile Software Development, Web Architecture, REST, Cross-platform, Mobile Development, Automation, Microservices, DevOps, Kanban, Azure DevOps, Agile, Desktop App Development, ETL, Offline-first Development, Database Design, Testing, Scrum, Test-driven Development (TDD), Event-driven Programming, Real-time Messaging Protocol (RTMP), HIPAA Compliance

Platforms

Software Design Patterns, Xamarin, Android, iOS, Azure, Windows UI, Windows, Mobile, Telerik, Twilio, Amazon Alexa, Amazon Web Services (AWS), Universal Windows Platform (UWP), Microsoft Bot Framework, Apache Kafka, Kubernetes

Storage

Microsoft SQL Server, IIS SQL Server, SQL Server 2016, Database Architecture, MySQL, Web Forms, Databases, JSON, API Databases, Azure SQL, MongoDB, PostgreSQL

Industry Expertise

Project Management, Healthcare

Other

Xamarin.Forms, Xamarin Studio, OData, Artificial Intelligence (AI), Web Development, Architecture, Full-stack, API Integration, APIs, WCF Web Services, PCI, Technical Architecture, Project Estimation, User Interface (UI), User Experience (UX), Fintech, Algorithms, Cloud Services, CI/CD Pipelines, Integration, Back-end, Data Analysis, Data Engineering, Data Scraping, Facebook, Single Sign-on (SSO), Authorization, User Authentication, Authentication, Software Architecture, Mobile App Development, Full-stack Development, Software Documentation, Development, MVP Design, SaaS, Subscriptions, Technical Leadership, Data Structures, Front-end, Startups, Distributed Systems, Instant Messaging, Minimum Viable Product (MVP), Cross-platform App Development, Cloud, Inventory Management, Offline Data Synchronization, Solution Architecture, Cloud Architecture, Deployment, App Store, Google Play Store, Mobile Apps, HTTPS, Webhooks, Scalable Web Services, Software System Design & Configuration, Android App Development, Leadership, Back-end Development, Software as a Service (SaaS), Software Design, Technical Requirements, Bots, Payment Gateways, OAuth, RESTFul APIs, Communication, Critical Thinking, Time Management, WebSockets, Intercom, SMS, AI Agents, AI Chatbots, CSV Export, Coding, Software Development, Data Migration, Security, Software, Mobile UI, CSV, Texting, Chatbots, Graphs, Charts, Dashboards, Payment APIs, Payment Processing, PayPal, IT Project Management, Intuit QuickBooks, Excel 365, IIS, Streaming, Broadcasting, Networking, Business Analysis, AI Integration, Budgeting, IT Management, Point of Sale, OpenAI, Machine Learning, FTP, SFTP, Web Server (IIS), Generative Artificial Intelligence (GenAI), Prompt Engineering, QuickBooks Online, eCommerce, Customer Relationship Management (CRM), OpenAI GPT-4 API, Spreadsheet Automation, QuickBooks Desktop, Customer Identity and Access Management (CIAM), Microsoft Entra External ID, Google Home, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), Algorithmic Trading, XML Web Services, Office 365, RTMP, Content Management Systems (CMS), Discord, Large Language Models (LLMs), Discord Bots, Futures, Okta

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