Pengfan Chang (John)
Crypto-friendly mobile engineer and outdoor research storyteller
I design privacy-first payment flows, resilient field apps, and Astro-powered publishing systems guided by time outside the lab.
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)
2 Peter 3:10-11
““But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up. Seeing then that all these things shall be dissolved, what manner of persons ought ye to be in all holy conversation and godliness,””
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.
IN 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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Accepts USDC, BTC, ETH, SOL & 150+ cryptocurrencies
Daily Picture
Random artwork sourced from The Metropolitan Museum of Art Collection