Andy is available for hire

Andy Gill

Verified Expert in Engineering

Xamarin.Forms Developer

Palm Beach Gardens, FL, United States

Toptal member since November 9, 2021

Bio

Andy is a full-stack developer with 20 years of experience in software. He is an expert in the .NET stack, from gathering requirements to SQL database design, web, Windows, and mobile back and front end, and deployed system monitoring and maintenance. His top skills include Xamarin Forms, conversational bots accessible via Amazon Alexa, Google Home, text messaging, and the full .NET stack in web or Windows applications. He enjoys solving problems that make the lives of his clients better.

Portfolio

Protos Security

Xamarin, Xamarin Studio, C#.NET, Mobile Development, iOS, Cross-platform...

Freelance

C#.NET, .NET 5, SQL, Telerik Kendo UI, Xamarin.Forms, Amazon Alexa, Google Home...

AMAG Technology

.NET, Angular, Xamarin.Forms, SQL, Windows Forms (WinForms), Mobile Development...

Experience

.NET - 20 years C#.NET - 20 years SQL - 20 years Software Design Patterns - 20 years Agile Software Development - 10 years Web Architecture - 10 years Xamarin - 8 years Xamarin.Forms - 5 years

Availability

Full-time

Preferred Environment

.NET

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

Mobile Developer

2022 - PRESENT

Protos Security

Developed Xamarin app to augment and eventually replace mobile website to manage guard activities.
Researched progress of .NET MAUI replacing Xamarin and updated management to help decide on an appropriate time to switch to MAUI.
Rewrote Xamarin app to .NET MAUI Blazor Hybrid to take advantage of sharing work between 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

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

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

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

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

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, PayPal API, Stripe, Stripe API, QuickBooks API, Google Maps, YouTube API, Node.js, React, Office 365 API

Tools

Microsoft Access, Git, WebView, Azure App Service, Zapier, GitHub, VPN, Azure OpenAI Service

Languages

SQL, C#.NET, JavaScript, HTML, HTML5, CSS, ASP.NET Razor, C#, XSD, XML, Visual Basic, VB.NET, Sass, C, TypeScript, 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, Blazor WebAssembly, ASP.NET MVC, 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, Real-time Messaging Protocol (RTMP), HIPAA Compliance

Platforms

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

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, 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, .NET 6, Back-end Development, Software as a Service (SaaS), Software Design, Technical Requirements, 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), Google Home, Artificial Intelligence (AI), 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)

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