
Patrick Keenum
Verified Expert in Engineering
Chrome Extensions Developer
Atlanta, GA, United States
Toptal member since July 6, 2018
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
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
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
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.
Principal Software Engineer
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.
Front-end Developer
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.
Full-stack Developer and Founder
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.
Full-stack Developer and Founder
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.
Full-stack Developer
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.
Full-stack Developer
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.
Full-stack Developer
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.
Full-stack Developer
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.
Full-stack Developer and Founder
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.
Full-stack Developer and Founder
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.
Full-stack Developer and Founder
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.
Full-stack Developer and Founder
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.
Experience
Influence (Unstoppable Games)
https://influenceth.ioI 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
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
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
LeadUp
Despicablimp
"Win It for Mom" Sweepstakes
ReactSnake
https://prof197.github.io/ReactSnake/Education
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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