Patrick Keenum, Developer in Atlanta, GA, United States
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Patrick Keenum

Verified Expert  in Engineering

Bio

Patrick is a senior full-stack engineer with nearly 20 years of experience developing beautiful, reliable, and scalable products. He is passionate about taking ideas from conception to launch, collaborating with clients of all technical acumen, and developing solutions that drive business growth.

Portfolio

Unstoppable Games
React, JavaScript, Three.js, React Three Fiber (R3F), HTML5 Web Workers...
Colliers International
Heroku, MongoDB, Elasticsearch, JavaScript, React, Material UI, Redis, CSS3...
BCG
JavaScript, Angular, D3.js, Python, CSS3, Front-end Development...

Experience

  • Node.js - 8 years
  • React - 6 years
  • TypeScript - 5 years
  • Angular - 5 years
  • Chrome Extensions - 4 years
  • OpenAI - 3 years
  • Three.js - 3 years
  • Next.js - 2 years

Availability

Part-time

Preferred Environment

Git, Visual Studio Code (VS Code)

The most amazing...

...project I've built was a suite of social games that grew to 6+ million monthly active users, honing my skills in creating scalable, engaging experiences.

Work Experience

Principal Software Engineer

2021 - PRESENT
Unstoppable Games
  • Developed a blockchain-powered MMO space strategy game, building on cutting-edge technology as it evolved, requiring rapid adaptation and problem-solving.
  • Engineered a progressive web app rendering 250,000 rotating asteroids with dynamically generated terrain and real astrophysics.
  • Optimized 3D graphics performance using quadtree-splitting for dynamic LOD, GPU memory management, and WebGPU, ensuring smooth rendering at scale.
  • Implemented high-performance rendering techniques with WebGL, Three.js, WebGPU, and offscreen canvas, leveraging web workers for parallel processing.
  • Integrated heavily with art, UI, and back-end teams, designing seamless interactions between game logic, visual fidelity, and blockchain infrastructure.
Technologies: React, JavaScript, Three.js, React Three Fiber (R3F), HTML5 Web Workers, Shaders, WebGL, MongoDB, Redis, Elasticsearch, WebGPU, WebGPU Shading Language (WGSL), CSS3, Node.js, HTML5 Canvas, Front-end Development, API Integration, Webpack, Docker, Koa, TypeScript, Architecture, APIs, New Products, Strategy, React Query, REST APIs, Unit Testing, Zustand, Axios, AWS SDK, Full-stack, Stripe API, Stripe, Web Development, Large-scale Projects, Web Security, Front-end, Sockets

Principal Software Engineer

2019 - 2021
Colliers International
  • Engineered internal data and mapping applications, integrating real estate intelligence and geospatial analytics to enhance decision-making for brokers and analysts.
  • Developed enterprise-grade Deal Room software that streamlined deal management and was widely adopted across global offices, improving efficiency and data transparency.
  • Optimized system performance and scalability, ensuring internal platforms could support thousands of concurrent users across multiple global locations.
  • Collaborated with stakeholders to digitize and automate workflows, reducing manual processes and increasing operational efficiency in deal tracking and client management.
Technologies: Heroku, MongoDB, Elasticsearch, JavaScript, React, Material UI, Redis, CSS3, Node.js, Front-end Development, API Integration, Webpack, Docker, Website Data Scraping, Web Scraping, Koa, Google Maps API, Architecture, APIs, Software as a Service (SaaS), Strategy, React Query, OAuth, REST APIs, Unit Testing, Axios, AWS SDK, Azure Active Directory, Active Directory (AD), Full-stack, Redux, Web Development, Babel, Web Security, Front-end, Sockets

Front-end Developer

2018 - 2019
BCG
  • Developed a high-performance front-end for a Fortune 100 airline's fleet optimization tool, ensuring a seamless transition for employees by mirroring their existing terminal GUI.
  • Engineered a virtualized UI to handle large datasets efficiently, leveraging D3.js and custom components to maintain usability and performance.
  • Collaborated with airline team leads to streamline UX, deeply understanding their workflows to optimize efficiency and minimize retraining.
  • Integrated closely with BCG's back-end and data teams, ensuring seamless data flow and functionality across the full optimization system.
Technologies: JavaScript, Angular, D3.js, Python, CSS3, Front-end Development, API Integration, Webpack, Bootstrap, APIs, REST APIs, Full-stack, Web Development, Web Security, Front-end

Full-stack Developer and Founder

2017 - 2019
Catalyst
  • Architected a matchmaking marketplace for HR service vendors and corporate buyers to connect and engage more effectively.
  • Created a chatbot that drove the generation of project briefs by corporate buyers for consumption by our vendor network.
  • Built a web crawler to seed our vendor database from publicly available vendor information.
  • Developed a Quora-like Q&A forum with threaded comments and a voting system.
  • Introduced a process-based dashboard for our sales team dashboard that integrated with HubSpot and Slack APIs to grow sales by $200,000 ARR in the first six months of launch.
  • Supported multiple subscription types and terms through Stripe API.
Technologies: Stripe API, HubSpot, Slack API, Sass, JavaScript, PHP, CSS3, Node.js, Angular, Chrome Extensions, Web Scraping, Chatbots, Front-end Development, API Integration, Website Data Scraping, Bootstrap, Google Maps API, Architecture, APIs, New Products, Software as a Service (SaaS), Strategy, Leadership, OAuth, REST APIs, Axios, AWS SDK, Full-stack, WordPress, WordPress API, Stripe, Web Development, Front-end

Full-stack Developer and Founder

2015 - 2017
LeadUp
  • Constructed a multitenant sales automation platform for managing outbound lead generation for SMB clients.
  • Implemented a design for multi-step, tokenized HTML email campaigns.
  • Leveraged automated email parsing and machine learning to maximize deliverability and semi-automated inbox management.
  • Built an API for clients to implement dynamic landing pages that would be personalized to the email recipient clicking through.
  • Designed a multivariate stat package to help clients benchmark and optimize their campaigns.
  • Integrated with Salesforce via API for clients to maintain data consistency with their internal teams.
  • Introduced role-specific Chrome extensions to improve each internal team’s throughput.
Technologies: Stripe API, Salesforce API, Slack API, Sass, JavaScript, PHP, CSS3, Node.js, Angular, Chrome Extensions, Web Scraping, Front-end Development, API Integration, Website Data Scraping, Bootstrap, Architecture, APIs, New Products, Software as a Service (SaaS), Strategy, Leadership, OAuth, REST APIs, Axios, Full-stack, Stripe, Web Development, Front-end

Full-stack Developer

2015 - 2015
NDA
  • Developed core technology for a commodities logistics company to provide a marketplace-style trading platform to its clients.
  • Automated discovery and cost calculation of the optimum real-time logistics path between any two client locations globally.
  • Implemented a bid/counter trading system that automatically adjusted the price spread based on logistics costs and desired profit margin per deal.
  • Integrated with Microsoft Dynamics NAV so completed trades could be initiated with the logistics team immediately.
Technologies: JavaScript, MongoDB, C#, Angular, Front-end Development, API Integration, Bootstrap, Google Maps API, APIs, New Products, REST APIs, Full-stack, Web Development, Web Security, Front-end

Full-stack Developer

2014 - 2015
Healthcare Bluebook
  • Worked with the client’s team to spec, design, and develop a new portal for their customers.
  • Aggregated several years’ worth of individual data points into useable structures for analysis.
  • Developed an interactive insights dashboard with d3.js that could be exported from the browser to PDF.
  • Designed a WYSIWYG editor that could generate HTML and PDF versions of marketing content.
Technologies: D3.js, jQuery, JavaScript, SQL, C#, CSS3, AngularJS, Front-end Development, API Integration, Bootstrap, APIs, Software as a Service (SaaS), REST APIs, Full-stack, Web Development, Web Security, Front-end

Full-stack Developer

2014 - 2014
Uniquely Virtual
  • Collaborated with the founder to design and deliver an MVP of her startup's core product.
  • Developed task management software designed specifically for interfacing clients with a team of virtualized executive assistants.
  • Enabled secure file-sharing, client-billing, time-tracking, and task workflows.
  • Implemented granular permission settings based on client ownership and admin level.
  • Integrated with Stripe API for one-billing and subscriptions.
Technologies: AngularJS, JavaScript, MongoDB, C#, Front-end Development, API Integration, Bootstrap, Architecture, APIs, New Products, Software as a Service (SaaS), REST APIs, Full-stack, Web Development, Web Security, Front-end

Full-stack Developer

2013 - 2014
Brandmovers
  • Worked with marketing team to implement social media marketing promotions, and web apps for their clients.
  • Contributed to projects for several major brands—Walmart, Best Buy, Dreamworks, Vizio, and Gate 1 Travel.
Technologies: jQuery, JavaScript, MySQL, PHP, Front-end Development, API Integration, APIs, OAuth, REST APIs, Full-stack, Web Development, Large-scale Projects, Front-end

Full-stack Developer and Founder

2012 - 2013
Pindex.jp
  • Designed and developed a mobile-optimized social curation app (like Pinterest) intended for the Japanese market.
  • Implemented multibyte character support for site language, user-generated content, and content search (via Sphinx).
  • Enabled streamlined image upload and processing for all curated content.
  • Leveraged Redis to create customized newsfeeds per user by managing individual subscriptions to multiple collection types.
Technologies: Amazon Web Services (AWS), jQuery, JavaScript, Redis, MySQL, PHP, Front-end Development, API Integration, Architecture, APIs, New Products, Strategy, REST APIs, AWS SDK, Full-stack, Web Development, Front-end

Full-stack Developer and Founder

2012 - 2012
MovieMix
  • Designed and developed a movie trivia game from scratch, including heavy animations and passive turn-based social gameplay.
  • Created a highly-interactive browser experience through the use of sound effects, animations, YouTube integration, and unlockable content and achievements.
  • Managed a team of three developers.
Technologies: Ember.js, JavaScript, MySQL, PHP, Front-end Development, API Integration, Architecture, APIs, New Products, Strategy, Leadership, OAuth, REST APIs, Full-stack, Web Development, Front-end

Full-stack Developer and Founder

2009 - 2011
GetYa Deals
  • Built a social media marketing platform designed for small businesses to incentivize customers to participate in social media marketing on their behalf via shares and reviews.
  • Developed a campaign designer tool for clients to quickly create and launch promotions, including automatic generation of campaign marketing materials (e.g., PDFs and QR codes).
  • Implemented a coupon management system, including managing generation and redemption via QR codes.
  • Utilized jqPlot to generate interactive campaign performance charting for clients.
  • Integrated subscription billing via ACH and CC using Authorize.net API.
  • Managed a team of two developers.
Technologies: jQuery, JavaScript, MySQL, PHP, Front-end Development, API Integration, Architecture, APIs, New Products, Software as a Service (SaaS), Strategy, Leadership, REST APIs, Full-stack, Web Development, Front-end

Full-stack Developer and Founder

2007 - 2010
Gangster Games
  • Designed and developed a suite of social gaming apps from scratch that grew to an active user base of over 6 million users.
  • Adapted the game suite to work with any major contemporary social network API: Facebook, MySpace, Bebo, and Orkut.
  • Optimized the virtual economy of each game to enable freeplay but encourage in-app purchases, premium subscriptions, and recruitment of other players.
  • Managed a team of six developers, split between onshore and offshore.
Technologies: jQuery, JavaScript, MySQL, PHP, Front-end Development, API Integration, Architecture, APIs, New Products, Strategy, Leadership, OAuth, REST APIs, AWS SDK, Full-stack, Web Development, Large-scale Projects, Front-end

Experience

Influence (Unstoppable Games)

https://influenceth.io
Served as a principal software engineer with a front-end focus on developing a blockchain-powered MMO space strategy game, requiring deep technical problem-solving in 3D graphics, WebGPU, and high-performance computing. The game featured 250,000 dynamically rendered asteroids with procedurally generated terrain, each with up to 1.7 million selectable plots, real astrophysics, and true-to-life time scales, necessitating chunk-splitting, dynamic level-of-detail (LOD), and heavy memory management to ensure smooth performance.

I developed the progressive web app (PWA) architecture, utilizing WebGPU, Three.js, and custom shaders to deliver a high-fidelity experience directly in the browser. This involved leveraging web workers, offscreen canvas rendering, and parallelized computations to optimize performance.

I collaborated closely with the art, UI, and back-end teams, integrating design assets, refining UX, and ensuring seamless synchronization with blockchain-based game logic. I also played a key role in debugging, profiling, and optimizing device performance, ensuring a smooth and engaging player experience.

VaccineList

Developed a real-time matching system to salvage otherwise discarded vaccine doses in the initial COVID-19 vaccine rollout by connecting providers with eligible recipients.

The system allowed pharmacies and vaccine providers to list extra doses that would need to be used before expiration due to the short shelf-life of open vials. It then used geolocation-based matching to identify the closest eligible recipients, prioritizing those in the highest-risk groups based on their eligibility phase. It factored in current driving conditions and estimated arrival times to ensure recipients could reach the vaccination site in time.

ElectionLab

Developed a data-driven election simulation platform that modeled voting trends using census data, historical precinct-level voting records, and geospatial data. The system analyzed demographic shifts, historical turnout, poll wait times, current COVID-19 data, and early/main-in voting patterns to simulate potential US election outcomes at a granular level.

The project required large-scale data processing. To handle the massive dataset efficiently, the system utilized distributed computing techniques, optimized queries, and in-memory data processing. The front-end visualized results interactively, allowing users to explore different simulation parameters and see their impact on projected outcomes.

Catalyst

Created a marketplace for HR service providers to interact more productively with corporate buyers. Features included a Quora-like Q&A board, comprehensive vendor directory, media dashboard, integrated sales tools for our outbound team, chatbot search tool for corporate buyers, and more. Grew the business to $200,000 ARR within six months of launch.

LeadUp

Constructed a multitenant sales automation platform to manage outbound lead generation for SMB clients. Built tools for prospecting, running multivariate data reports, designing tokenized HTML email campaigns, and managing campaign responses. Utilized machine learning to increase email deliverability and semi-automate prospecting and inbox management over time. The business grew to $1 million ARR.

Despicablimp

Helped redesign a fun single-page application used to track and sharing photos of the Despicablimp: a cartoon-shaped blimp that traveled the country to promote the opening of Despicable Me 2.

"Win It for Mom" Sweepstakes

Developed a video submission contest for Mother's Day 2013, then reskinned it and repeated for Father's Day. Partners sponsoring the projects included Vizio, BestBuy, DreamWorks, and Walmart.

ReactSnake

https://prof197.github.io/ReactSnake/
Created an homage to the old-school "Snake" game that came built-in on pre-smart cellphones. This was an afternoon project to my first app with React.

Education

2003 - 2007

Bachelor of Engineering Degree in Computer Engineering & Mechanical Engineering

Duke University - Durham, North Carolina

Skills

Libraries/APIs

jQuery, Node.js, Stripe API, React, Three.js, HTML5 Canvas, React Query, REST APIs, Stripe, Sockets, D3.js, Google Maps API, SendGrid API, Slack API, HTML5 Web Workers, WebGL, WebGPU, WebGPU Shading Language (WGSL), OpenAI API, WordPress API, Salesforce API, Authorize.net, Twilio API

Tools

Git, NPM, Webpack, AWS SDK, Subversion (SVN), MATLAB, Babel

Languages

JavaScript, CSS3, HTML5, PHP, TypeScript, SCSS, C#, Sass, SQL, Java, C++, Assembly, Python, GraphQL

Frameworks

Express.js, AngularJS, Bootstrap, Angular, Koa, Redux, Material UI, Next.js, Ember.js, LibGDX, Android SDK, React Native, Tailwind CSS

Paradigms

Unit Testing, Object-oriented Programming (OOP), Design Patterns

Storage

MongoDB, MySQL, Memcached, Redis, Elasticsearch, PostgreSQL, Amazon S3 (AWS S3), Sphinx Search Engine, Azure Active Directory

Platforms

Linux, Heroku, Starknet, WordPress, HubSpot, Amazon Web Services (AWS), Azure, Amazon EC2, Android, Visual Studio Code (VS Code), Docker, Blockchain

Other

Front-end Development, React Three Fiber (R3F), API Integration, Chrome Extensions, Chatbots, AI Chatbots, Architecture, APIs, New Products, Software as a Service (SaaS), Strategy, Leadership, OAuth, Zustand, Axios, Full-stack, ChatGPT API, Web Development, Large-scale Projects, Front-end, Shaders, OpenAI, AI Integration, AI Agents, Agentic AI, 3D Graphics Engines, Web Scraping, Website Data Scraping, Generative Pre-trained Transformers (GPT), Web Security, Data Structures, Computer Architecture, Operating Systems, Signal Processing, Computer Networking, Fault Tolerance, Performance Optimization, Distributed Systems, LangChain, SVG Animation, Cairo, Big Data, Active Directory (AD)

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