Justin Garcia
iOS and speech AI
Email | GitHub | LinkedIn
I have over 16 years of software engineering experience, including 9 years at Apple on iOS text input and WebKit's editing engine. I now ship speech AI products and internal tools for Kotoba: Japanese on-device text-to-speech for mobile, eval infrastructure, and a meeting bot. I still specialize in iOS.
Experience:
Kotoba (August 2025 - Present)Tokyo
Senior Software Engineer
I work at Kotoba, a frontier speech AI company in Tokyo.
  • Helped build subscriptions into Kotoba’s low-latency speech translation app, which reached $400k USD ARR in 5 months
  • Helped ship Kotoba’s on-device Japanese text-to-speech for mobile. Improved inference performance and memory footprint
  • Built release automation for iOS, Android, and OTA updates, and automated benchmark runs for new speech-to-speech translation models
Independent (April 2024 - August 2025)Tokyo
Took a Rails class in Tokyo, built most of the backend for a YouTube summarizer, and other personal projects.
Procore (July 2018 - March 2024)California
Senior iOS Software Engineer
I worked on Procore for iOS, a project management app for the construction industry.
  • Built the iOS subsystem that lets enterprise clients like Amazon customize the app
  • Fixed 50+ high-volume crashes impacting customers
  • Cut iOS build time by ~20% (30s) by extracting stable code into a prebuilt binary
iHeartMedia (December 2016 - October 2017)New York
iOS Software Engineer
I worked on iHeartRadio for iOS, a music streaming app.
  • Shipped redesigned podcast browsing and playback
Musey (July 2015 - October 2015)San Francisco
iOS Developer
Musey was a short-lived startup in San Francisco. We created an iOS app for photo sharing.
Apple (June 2005 - April 2014)Cupertino
Software Engineer
  • Led development on keyboard dictation for Siri’s initial release
  • Made Cut / Copy / Paste fast enough for the first iPhone (performance tuning)
  • Maintained WebKit’s WYSIWYG editing engine (which powers Mail) for 3 years
  • Presented at WWDC in 2011 and 2012 on the iOS text input system
  • Built most of the Siri streaming animation that was new in iOS 8
  • Implemented part of Safari’s Safe Browsing feature, which protects users from malicious content
My Apps:
Ume: autofill everything, privately
Kehai: tame your windows and switch apps faster
Sasu: on-screen guidance for foreigners living abroad
Yubi (coming soon): translate what’s on screen and what you type
Education:
Rice University (September 2001 - May 2005), B.A. in Computer Science
Patents:
Mapping application search function (Apple)