Pengfan Chang (John)
Multi-platform developer & researcher
Building native experiences across GNU/Linux, macOS, iOS, iPadOS, watchOS, visionOS, and Android with Swift, Java, and Kotlin.
Specializing in Data Analysis, privacy-first payment flows, and computational communication research.
GO Shipping Kotlin + Swift features, NOWPayments subscriptions, and data automations for indie media teams.
Android Lab
Jetpack Compose + Kotlin craftsmanship
Apple R&D
SwiftUI explorations on macOS & iOS
Data Ops
Excel · SQL · Python automation loops
Field Notes
Outdoor research fueling product ideas
Daily Verse · Holy Bible (KJV)
Isaiah 7:14
““Therefore the Lord himself shall give you a sign; Behold, a virgin shall conceive, and bear a son, and shall call his name Immanuel.””
Verse supplied by BibleGateway.com (KJV) with offline fallbacks for reliability.
ST Skills & Technologies
CF Current Focus
Android & Kotlin
Compose-first product experiments with secure deliveries.
Swift & SwiftUI
Native experiences tuned for macOS, iOS, and watchOS.
Data Pipelines
Excel models, SQL warehousing, and resilient ingestion scripts.
Decision Dashboards
Polished visual stories that elevate analytics.
RI Research Interests
CS Computer Science Interests
FP Featured Projects
View All →Google Chrome Extension for enhanced browsing with journal ranking and AI-powered summaries
Adobe After Effects tutorial for creating stunning 3D traditional Chinese ink-style text effects
One Tool, Multiple Solutions - Replace dozens of separate utilities with a single, powerful CLI.
OS Organizations I Support
Supporting the fight for digital freedom, privacy, and free software
Free Software Foundation
Fighting for user freedom in the age of computing
Electronic Frontier Foundation
Defending civil liberties in the digital world
Trisquel OS
Fully free GNU/Linux distribution
Purism
Privacy-respecting laptops & phones
Libreboot
Free and open source BIOS/UEFI firmware
NOWPayments
Accept crypto payments easily
Connect
Support My Work
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Daily Picture
Random artwork sourced from The Metropolitan Museum of Art Collection