I'm a principal software engineer, and I've been writing performance‑sensitive software for more than 20 years: Roku video players, C++ game engines, and a tolling system that handles millions of transactions a day. I like problems where a user can tell whether the engineering was any good. A video that stutters is one of those.
Most recently I worked on the Peacock video player on Roku at NBCUniversal. Before that I led the team that owned the Roku Video Player in Comcast's Xfinity Stream channel, which millions of subscribers use. I've also shipped Halo Infinite gameplay at 343 Industries, built the Roku channel for The Church of Jesus Christ of Latter‑day Saints end to end (it's live as Gospel Stream), worked on discovery+ at Warner Bros. Discovery, and led an augmented reality project for NIST that put HoloLens 2 tools in the hands of first responders.
I've run NJLIGames since 2010. It became NJLIGames Ltd in 2015, and my own cross‑platform C++ engine runs more than ten of its games and VR experiences. Earlier I shipped seven Nintendo DS, DSi, and Game Boy Advance titles, including MLB 2K10 and Glow Artisan, which won Best Mobile Game Design at the 2010 Independent Games Festival Mobile awards. The full credit list is in my game development portfolio, and two of the games there are playable right now. I've written Lua for 15 years, and I mentor developers on Codementor, where my rating is 5.0.
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2026
Senior Roku Developer · NBCUniversal
Worked remotely on the Peacock video player for Roku. Stabilized a unit‑test suite that kept crashing (it's built on Rooibos, the open‑source BrightScript test framework), added Adobe Edge analytics events for product and marketing, and removed a legacy Promise dependency.
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2024 - 2026
Senior Software Engineer · Neology
Designed multithreaded real‑time software for roadside tolling. The system processes millions of micro‑transactions a day, and each one has to be fast and correct. I worked on both the roadside and the back‑office subsystems.
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2023 - 2025
Principal Roku Developer · Comcast
Led the team that owned the Roku Video Player, used by millions of Comcast subscribers. Integrated the Roku Ad Framework into VOD, with SCTE‑35 signal parsing and a FreeWheel ad‑URL system. Was technical lead on the Roku Interstitial Library integration, which grew linear ad revenue 300%. Wrote the RFC 6570 URITemplate library the HLS to DASH migration was built on.
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2021 - 2023
Principal Roku Developer · The Church of Jesus Christ of Latter‑day Saints
Led development of the Church's Roku channel, now live as Gospel Stream. It carries general conference, which the Church says reaches millions of people in more than 70 languages. Added resume playback using the Roku registry and integrated the Youbora SDK for analytics and ads.
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2020 - 2022
Senior Software Engineer · Warner Bros. Discovery
Built screens and extended the event system in the discovery+ Roku app. Added VoiceOver support to the discovery+ iOS and tvOS apps in Swift. Integrated the Kochava SDK, and wrote a Python and Doxygen pipeline that generates API docs from inline BrightScript comments.
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2021
Halo Gameplay Engineer · 343 Industries
Worked on Halo Infinite gameplay in C++ and Lua. Added and improved gameplay features and fixed gameplay bugs.
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2010 - Present
Founder & Principal Software Engineer · NJLIGames Ltd
Designed and maintain a proprietary C++ game engine that runs on Windows, Linux, macOS, iOS, and Android. More than ten original games and VR experiences run on it, played by thousands of people. The studio also shipped the Gospel Stream channel to the Roku channel store, and it builds apps and SaaS products.
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One Group Central
A private member portal for organizations such as unions and HOAs. It has documents, announcements, chat, events, polls, and cryptographically anonymous voting recorded on an append‑only hash chain. I built all of it: the C++ (Crow) backend, Flutter clients for six platforms, Stripe billing, and the admin console.
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PostBaton
A social media scheduler that publishes to eleven platforms. The engine is built around idempotency, so each post goes out exactly once and on time, and a failure gets reported instead of swallowed.
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Musicianle
A daily music guessing game. You see a musician's discography with the names masked and get eight guesses to name them. The backend is C++20, the client is Flutter, and it's free.
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East the Beasts
An independent press. It publishes structured journals like The 90 Day Field Manual, sudoku and activity books, and illustrated children's books, and sells them direct.
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Reword Me
An iMessage extension that rewrites a message in clear, simple language without leaving the conversation. It supports Dark Mode, Dynamic Type, and VoiceOver, and it's on the App Store.
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NJLIGames
My studio since 2010, and where everything above lives: the C++ engine, the console and mobile games, and the apps and SaaS products.
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jamesfolk.me
This site. Hand‑written HTML and CSS with a little vanilla JavaScript, no framework and no build step, plus structured data so search engines know who it's about.
I consult on Roku and connected‑TV projects through my studio (see Roku channel development). If you're doing senior or principal engineering in streaming, games, or systems, I'm happy to compare notes. Email is the fastest way to reach me.