Ken is available for hire

Ken Hoffman

Verified Expert in Engineering

Full-stack Developer

Chandler, AZ, United States

Toptal member since August 27, 2018

Expertise

Software Development Full-stack Visual Studio Development VB.NET .NET REST API API Web Development C#LLM OpenAI SQL Bootstrap IIS

Bio

Ken has 20+ years of experience as an independent contractor, providing application development services to his customers. Recently, he's honed his skills in building applications that utilize AI on the back end, as well as utilizing AI developers (auto-devs), resulting in rapid and high-quality application development. Ken's motivation to deliver value-added solutions and bring projects to a successful completion has earned him the respect of his clients, resulting in long-term relationships.

Portfolio

Northrop Grumman Innovation Systems (Contractor)

Bootstrap, Microsoft SQL Server, ASP.NET, .NET, .NET 4

Trelleborg Corporation (Contractor)

Microsoft SQL Server, ASP.NET, .NET, .NET 4, eCommerce

Dataforth Corporation (Contractor)

Bootstrap, Python, Microsoft SQL Server, ASP.NET, .NET 4...

Experience

Full-stack Development - 20 years
Microsoft SQL Server - 20 years
Code Architecture - 20 years
Software Development - 20 years
C#.NET - 10 years
ASP.NET Core - 6 years
Minimum Viable Product (MVP) - 5 years
OpenAI - 2 years

Preferred Environment

Git, Visual Studio, Claude, Claude API, Azure

The most amazing...

...project I've worked on was developing a property-tech company using a team of AI developer agents (auto-devs).

Work Experience

Full-stack Web Developer

2016 - PRESENT

Northrop Grumman Innovation Systems (Contractor)

Cooperated with a team on creating an initial concept to obtain project approval and funding.
Developed a full-stack solution for an application and its supporting processes.
Implemented robust security measures to meet the Department of Defense's standards and requirements.
Created an administrative module with complex user roles.

Technologies: Bootstrap, Microsoft SQL Server, ASP.NET, .NET, .NET 4

Full-stack Web Developer

2006 - PRESENT

Trelleborg Corporation (Contractor)

Created an eCommerce portal to automate and track online requests for quotes and purchase orders from high-value customers.
Constructed a product database application that enables the full management and multi-tiered pricing of multiple product catalogs.
Implemented a reporting system to generate various accounting and sales reports based on the activity on the site.
Provided full-stack development for the creation and maintenance of an eCommerce portal and its supporting applications.
Collaborated with the management on identifying value-added improvement opportunities.

Technologies: Microsoft SQL Server, ASP.NET, .NET, .NET 4, eCommerce

Full-stack Web Developer

2000 - PRESENT

Dataforth Corporation (Contractor)

Provided full-stack development of an enterprise website.
Managed several migrations to new generations of site features and capabilities.
Created a system configuration tool that enables customers to build, configure, and price data acquisition systems.
Implemented the use of Bootstrap in a website to facilitate a responsive UI.
Constructed sync processes that allow the site to perform real-time sync with an email marketing database, using REST API.

Technologies: Bootstrap, Python, Microsoft SQL Server, ASP.NET, .NET 4, Active Server Pages (ASP), User Interface (UI), REST APIs

Solution Architect and Developer

2019 - 2021

Freelance Application Developer

Constructed an app that allows superintendents to manage the team's assignments, allowing team members to track progress as well as track and submit timecards.
Built a back end to integrate multiple third-party services with an ERP system via API integration.
Created an API to expose the features of the application.
Developed ASP.NET MVC front end utilizing the Bootstrap theme.
Cooperated with the client's team from inception to production to capture business needs, evaluate feedback, and optimize overall utilization and acceptance.

Technologies: .NET Core, JavaScript, SQL Server 2016, ASP.NET MVC, C#

ASP.NET Developer for Website Revamp

2018 - 2019

Air-Tite Products (via Toptal)

Created a custom search tool that integrated with the existing AspDotNetStorefront platform.
Facilitated the reskin of an existing AspDotNetStorefront site.
Participated in the lightning start process to create the initial proposal and scope of work.
Managed, as a lead developer, the development team, using an agile environment during the 10-week project.
Interacted and communicated with the client to understand the project goals and requirements fully.

Technologies: AspDotNetStorefront, C#.NET, ASP.NET MVC, .NET, .NET 4

Software Developer

2002 - 2018

Leading Semiconductor Manufacturer (Contractor)

Developed a Windows desktop application to provide the worldwide sales force with a product data repository, search, and presentation capabilities.
Improved an application and enabled it to function without an internet connection, with a sync utility that updates all data and content when the network connection was available.
Integrated several product search tools for a wide variety of semiconductor product offerings.
Created a presentation system to autogenerate sales presentations from structured data and account for a wide variety of screen and projector sizes.
Built several back-end batch processes to automate data transformation from a range of sources to a common snapshot for client-sync availability.

Technologies: Microsoft Access, ASP.NET, VB.NET, .NET, .NET 2, Xamarin, C#

Experience

Property-tech Solution

A property-tech solution for a startup. I was the solution architect and full-stack developer responsible for creating the MVP for this product. This solution consisted of a React front end and a .NET back end, both hosted on Azure. The project also involved ingesting MLS data and utilizing Azure Data Factory for data synchronization. I utilized AI developers (auto-devs) as my development team for both the front end and back end to deliver high-quality and high-speed application development.

AI-driven Document Recognition and Extraction

I worked with a startup to create the MVP product, an AI-driven solution that facilitates mortgage loan applications by auto-identification and data extraction of consumer loan documentation to auto-fill mortgage applications. I was a solution architect and back-end developer who worked on integration and prompt engineering with the OpenAI API.

SaaS Cloud Solution for Property Tax Consultants

I developed the next-generation solution for a SaaS solution that provides services to property tax consultants. I designed the architecture and led a team of developers to build back-end, front-end, and API components for the next-generation solution.

ASP.NET Core - Workflow Automation Application

Developed an ASP.NET Core 2.2 application that manages and automates the workflow processes of a language translation company. This application integrates with multiple external APIs and automates workflow assignments and messaging.

ASP.NET MVC - Corporate Training Application

Developed a training application for a large corporation using ASP.NET MVC, SQL Server, and SCORM Cloud API. The application is equipped with both administration and learner interfaces that constitute a complete online training platform.

Data Acquisition System Builder

https://www.dataforth.com/data-acquisition-system-builder.aspx

Created a data acquisition system builder application that guides users through the creation of a viable data acquisition system.

Air-Tite Website Redesign and Search Tool

As the lead developer for a Toptal project for Air-Tite, I redesigned the company's website. This project included direct communication with the client to fully understand the project goals and requirements. As part of this project, I developed a custom search tool that integrated with the existing eCommerce platform, using AspDotNetStorefront.

Real-time Interactive Demo

I created a demonstration page on an ASP.NET website that enabled users to experience real-time feedback of a data acquisition system. This system included a live, low-latency video stream, and HTML5 interactive controls. I created a Python server component to interface with the hardware system API.

RMA Module

I developed an online return merchandise authorization (RMA) feature on an existing website and integrated it with the existing user and admin roles database. The feature tracks RMAs through the entire process and makes status updates available at all times in both the customer and admin views.

Sync Feature

I developed a synchronization feature for a desktop application. The network-aware sync feature managed data, collateral incremental updates, and feedback data to the server.

Healthcare Coaching App MVP

I architected and developed a coaching platform for a healthcare and longevity company. This HIPAA-compliant platform facilitates communication between providers, coaches, and patients, integrates with EMRs, and includes both patient-facing and coach-facing apps.

Education

1988 - 1989

Bachelor of Science Degree in Mechanical Engineering

University of Arizona - Tucson, AZ

Skills

Libraries/APIs

REST APIs, React, OpenAI API, Entity Framework, Claude API

Tools

Visual Studio, AspDotNetStorefront, AI Prompts, Git, Microsoft Access, Claude, ChatGPT

Languages

Python, C#.NET, Visual Basic .NET (VB.NET), C#, Active Server Pages (ASP), SQL, HTML5, JavaScript, VB.NET, Java, Python 3, Transact-SQL (T-SQL), HTML, CSS

Frameworks

ASP.NET Web API, ASP.NET, ASP.NET MVC, .NET 4, ASP.NET Web Forms, ASP.NET Core, .NET, Bootstrap, AngularJS, .NET 2, .NET Core, ASP.NET Core 2, .NET 8

Paradigms

API Architecture, SCORM, Azure DevOps, Automation, HIPAA Compliance

Platforms

Android, Windows, Azure, Xamarin

Storage

SQL Server 2016, Microsoft SQL Server, Jet SQL

Industry Expertise

Healthcare

Other

IIS, Software Development, Full-stack, APIs, Code Architecture, Full-stack Development, Minimum Viable Product (MVP), Software Architecture, Software Design, OpenAI, OpenAI SDK, AI Agents, Optical Character Recognition (OCR), Large Language Models (LLMs), Lovable, eCommerce, User Interface (UI), Data, Applications, Web Development, API Integration, Supabase, Enterprise Resource Planning (ERP)

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