David Reinert, Developer in Schnecksville, PA, United States
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David Reinert

Verified Expert  in Engineering

Software Developer

Schnecksville, PA, United States
Toptal Member Since
June 30, 2020

Dave is an enthusiastic software developer who excels at creating feature-rich, single-page applications, integrating 3rd-party technologies, refactoring legacy projects, and CI/CD pipelines. He goes above and beyond for clients, striving to deliver top-quality work that updates and optimizes code, ensuring fast and stable output. His expertise with React, C#.NET, and Microsoft SQL Server has significantly improved old code and processes and created exciting new, high-performing functionality.


Tandem Diabetes Care
React, JavaScript, .NET, Material UI, Webpack, Single Sign-on (SSO), OAuth 2...
AWeber Inc.
JavaScript, React, Webpack 5, React Router, PHP, React Redux, Redux, MVC Design...
Silly Moose LLC
PHP, MongoDB, HTML, JavaScript, CSS, HTML5, jQuery, MySQL, Svelte, Tailwind CSS...




Preferred Environment

MongoDB, Azure, Bootstrap, Laravel, TypeScript, React, Node.js, JavaScript, Entity Framework, C#.NET

The most amazing...

...full-stack project I've designed and developed from scratch was a social networking application.

Work Experience

Senior Front-end Engineer

2024 - PRESENT
Tandem Diabetes Care
  • Mentored a junior front-end developer to ensure he can grow into his role and succeed.
  • Implemented major user flows and upgraded existing components.
  • Migrated the single sign-on process away from Okta to IdentityServer.
Technologies: React, JavaScript, .NET, Material UI, Webpack, Single Sign-on (SSO), OAuth 2, Okta, Cypress, Front-end, Web Development, Single-page Applications (SPA), Figma, REST APIs, APIs, TypeScript, Code Review, Technical Leadership, Git

Senior Full-stack Developer

2021 - 2024
AWeber Inc.
  • Promoted into the role of a senior developer in less than six months.
  • Led the effort to move the application architecture away from a single monolithic web application and towards a micro-frontend architecture powered by Webpack 5 Module Federation.
  • Took the initiative on multiple projects to update and improve the architecture and test coverage.
  • Built numerous reusable UX components that are used across teams.
Technologies: JavaScript, React, Webpack 5, React Router, PHP, React Redux, Redux, MVC Design, Scrum, Software Engineering, Cypress, Front-end, Web Development, Architecture, Single-page Applications (SPA), Figma, REST APIs, APIs, TypeScript, Code Review, PHP 7, Technical Leadership, Database Structure, Database Architecture, Git, Tailwind CSS, SCSS

PHP Developer

2020 - 2024
Silly Moose LLC
  • Oversaw upgrade of the application stack from obsolete PHP 5.3 to the latest PHP 8.1. This included updates to the Docker image, application dependencies, and application code to execute this massive undertaking.
  • Designed and implemented Svelte applications as part of a major overhaul to be the most trafficked page in the application. Implemented a modern design system and integrated the Svelte application into the larger legacy JavaScript on the page.
  • Overhauled the front-end build system with Gulp to improve the front-end build and deployment processes vastly. Built a custom pipeline to facilitate features such as automatic cache busting and bundle optimization.
  • Designed and developed full-fledged application features of customers single-handedly. This includes the back-end design of relevant models/schemas and the necessary UI/UX front-end design.
  • Refactored major pieces of existing functionality to facilitate better maintainability and more expedient additions to that existing functionality as requested by customers.
Technologies: PHP, MongoDB, HTML, JavaScript, CSS, HTML5, jQuery, MySQL, Svelte, Tailwind CSS, Docker, Full-stack, Front-end, Web Development, Architecture, REST APIs, PHP 8, APIs, Code Review, PHP 7, Database Architecture, Technical Leadership, Git, Vue, SCSS

React Software Engineer

2022 - 2022
Productboard, Inc
  • Led and mentored an entire team of React developers to navigate a large existing code base and take ownership of existing modules.
  • Reworked existing routing logic and flows, coordinating with back-end engineers to support new functionality and requirements from the product.
  • Developed reusable components and shared them across the team, ensuring my fellow team members could work smarter, not harder, when delivering their features.
Technologies: React, JavaScript, TypeScript, Software Engineering, Node.js, Front-end, Web Development, Single-page Applications (SPA), REST APIs, APIs, Code Review, Database Architecture, Git, SCSS

Full-stack Developer

2020 - 2021
Cox Automotive, Inc.
  • Developed and maintained shared modules to facilitate shared state between Micro Frontend apps, including designing and implementing a shared authentication solution that could be exported to and consumed by the Micro Frontend apps.
  • Introduce TypeScript to existing React applications.
  • Mentored other team members on React best practices and the newer React features.
Technologies: C#.NET, React, React Redux, AWS Lambda, Amazon DynamoDB, Amazon Web Services (AWS), React Router, .NET Core, MVC Design, REST, Scrum, NoSQL, Software Engineering, Full-stack, ASP.NET, Front-end, Web Development, Architecture, Single-page Applications (SPA), REST APIs, Microsoft Azure, APIs, TypeScript, Code Review, Git, SCSS

Full-stack Software Developer

2020 - 2020
Law School Admission Council
  • Developed a feature-rich application with a mature React front end and .NET Service Fabric back end. Worked across the entire tech stack to deliver new features.
  • Served as the primary technical resource for React best practices and design and implementation questions and concerns.
  • Coordinated with other teams to accomplish larger feature goals that spread across the application.
Technologies: Microsoft SQL Server, Entity Framework, Azure, Azure Service Fabric, Redux, React, C#.NET, .NET Core, MVC Design, REST, Scrum, Software Engineering, Full-stack, ASP.NET, Front-end, Web Development, Architecture, Single-page Applications (SPA), REST APIs, Microsoft Azure, APIs, TypeScript, Code Review, Database Architecture, Git, SCSS


2019 - 2020
Trifecta Technologies
  • Assisted as the primary architect on a social networking application for the Juvenile Diabetes Research Foundation. Designed the entire application stack as well as the supporting cloud infrastructure.
  • Mentored other developers on the team on the technology stack as they were not as familiar with it as I was, often working extra hours and weekends to help get work items to the finish line in any given sprint.
  • Worked to incorporate multiple third-party dependencies into the application as required by the client.
  • Contributed heavily across the stack, from back-end work on the API and database layers to front-end work on the React app covering both functionality and design work.
  • Trusted with all technical decisions as client requirements evolved and guided the development team as those decisions were made.
Technologies: Entity Framework, Node.js, Docker, SignalR, MongoDB, SQL, Azure, Redux, React, C#.NET, .NET Core, REST, React Native, Scrum, Software Engineering, ASP.NET, SQL Server 2014, Front-end, Web Development, Architecture, Single-page Applications (SPA), REST APIs, Microsoft Azure, APIs, TypeScript, PHP 7, Database Architecture, Git

Software Developer

2018 - 2019
Seed Development
  • Developed comprehensive application tests to allow for independent verification of back-end functionality by anyone on the team.
  • Built features that integrated with a variety of third-party APIs and technologies via exposed REST endpoints.
  • Overhauled a legacy PHP web application back-end to function strictly as a back-end service for a single page application powered by Laravel.
  • Refactored a legacy web application to utilize a single-page application paradigm leveraging Angular 6 over the existing multi-page JavaScript/jQuery architecture, improving maintainability and scalability across the entire development team.
Technologies: Language Understanding Intelligent Service (LUIS), Microsoft Bot Framework, C#.NET, SQL, Azure, Angular, Laravel, PHP, .NET Core, MVC Design, REST, Software Engineering, ASP.NET, SQL Server 2014, Front-end, Web Development, Single-page Applications (SPA), REST APIs, Microsoft Azure, APIs, PHP 7, Database Architecture, Git

Junior Full-stack Developer

2016 - 2018
Ideal Concepts
  • Developed, maintained, and wrote functionality for web applications critical to everyday business operations.
  • Integrated SQL Server databases via a managed data access layer that I overhauled and upgraded.
  • Updated existing web applications on a cross-functional and multi-office team using JavaScript.
Technologies: Microsoft SQL Server, Entity Framework, C#.NET, JavaScript, ASP.NET, SQL Server 2014, APIs, Database Architecture, Git

Knowledge Owl

A knowledge base platform that enables the development of feature-rich knowledge bases with completely custom themes, user experiences, and content. Countless tools and features give users full control over their content as well as the consumers of the content. Numerous metrics and reports are also made available and the account settings and customizations are endless.

JDRF Connect

This is a social networking application for the Juvenile Diabetes Research Foundation (JDRF), which exists under the current branding. It was built from scratch.

I was the primary architect, integrating with their existing authentication systems. The application was entirely hosted in the cloud via the Azure cloud platform. It utilized SQL and NoSQL data stores, which were exposed via a .NET Core REST API hosted out of Azure App Service. It also leveraged Entity Framework Core to facilitate data access and drive database design. It also used SignalR to allow for real-time messaging and notification features.

The application UI/UX was delivered via a React-Redux SPA, built, and served as a static resource from Azure CDN. Docker was used during local development to ensure consistency and expediency for easy and fluid development environments that replicated this cloud infrastructure.

I was solely responsible for these architectural decisions, driving both front- and back-end development and implementing and maintaining the CI/CD pipeline in Azure DevOps. I served as the resident expert across the application stack, leading the team from sprint to sprint as the client's requirements grew and changed.

LiveWell at Citi

An employee fitness application for Citibank that came with an existing PHP web application was dated and not well-maintained.

Without senior guidance or direction, I undertook the task of bringing the existing application codebase into the 21st century. This required pulling apart the existing codebase to separate concerns. The front end was overhauled from a complicated mess of JavaScript and jQuery into a modern Angular SPA. The PHP was refactored to function as a back-end REST API for the web and companion mobile applications.

This ensured we could deliver the kind of full-featured enterprise web application our client demanded. It also reduced the development pain points for my fellow team members, ensuring there were fewer obstacles for them to overcome in delivering features. This required a deep dive into uncharted territory, rapidly developing my understanding of entirely new technology stacks and frameworks while regularly communicating changes throughout the rest of the team.

TD Ameritrade Chatbot

A chatbot platform built using the Microsoft Bot Framework and LUIS for natural language processing, integrating with numerous platforms, both text (Twitter, Facebook, Apple Business Chat, and WeChat) and voice (Alexa and Google). All of these integrations were supported by two .NET Core APIs.

The first was the connector layer, which would serve as the REST entry point for the various platforms to relay messages to. When the message came in on a given channel, the connector layer would take that JSON payload and translate it into a single data structure that the Microsoft Bot Framework could understand. It would then transmit this payload to a second API, which contained all the business logic, TD Ameritrade API integrations, and NLU processing. That API would generate a response that was sent back through the connector layer, where it would be translated again into the payload the channel could then understand and render to the end-user.

I was actively involved in development across all aspects of this system, which required thorough understanding, not only of the business rules but also the array of platforms we supported and the difference between them to ensure consistency across platforms.

AWeber App Shell

AWeber provides businesses with an email marketing platform. Historically, that platform has been powered by a monolithic, legacy PHP application. AWeber started to move these legacy PHP pages to single-page applications powered by React, but this still resulted in a disjointed set of pages being served by the PHP monolith instead of a seamless user experience.

I identified this issue early in my tenure at AWeber, along with a solution—the app shell. Using module federation to load applications dynamically at run time, the app shell would be served across a range of URLs on the initial page load. From there, it would take over routing users between the various applications using client-side routing, providing a seamless web application experience. This required tackling a range of issues, from data management to styling. It was a months-long effort that required dedication and determination. It is now being served to all of AWeber's customers, and the feedback has been overwhelmingly positive.
2012 - 2016

Bachelor of Science Degree in Computer Science and Physics

Muhlenberg College - Allentown, Pennsylvania, USA


React, Entity Framework, React Redux, REST APIs, Node.js, React Router, Vue, SignalR, jQuery, jQuery UI


Git, Webpack 5, Figma, Language Understanding Intelligent Service (LUIS), Gulp, Webpack


Redux, .NET, .NET Core, Tailwind CSS, Angular, Express.js, ASP.NET, Laravel, React Native, Bootstrap, Svelte, Material UI, OAuth 2, Cypress


C#.NET, JavaScript, TypeScript, C#, PHP, HTML, PHP 5, SQL, PHP 7, CSS, PHP 8, SCSS, HTML5


REST, MVC Design, Scrum


NoSQL, Database Architecture, MongoDB, MySQL, Microsoft SQL Server, Amazon DynamoDB, SQL Server 2014, Database Structure


Azure, Docker, Azure Service Fabric, Microsoft Bot Framework, AWS Lambda, Amazon Web Services (AWS), Amazon Alexa


Software Engineering, Front-end, Web Development, Architecture, Single-page Applications (SPA), APIs, Technical Leadership, Computer Science, Full-stack, Microsoft Azure, Code Review, Single Sign-on (SSO), Okta

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