1
I accidentally became PureGym’s unofficial Apple Wallet developer
How I reverse-engineered PureGym's API to build a working Apple Wallet pass with PassKit, Vapor, and mitmproxy - end-to-end iOS reverse engineering walkthrough.
Vadim Drobinin
Senior iOS engineer & consultant. 15+ years shipping apps for medical, fintech, and consumer. SwiftUI, TCA, on-device ML, HIPAA. Apps acquired by Twitter, featured by Apple, CES & Webby honours.
- Popular posts
- 8
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- 2,273
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- 912
- Rank
- #703 personal
Visit drobinin.com → RSS feedOn Hacker News Dec 2019 – May 2026
Life, Learning & Writing 5Software Engineering 3Web & Frontend 1Society, Policy & Culture 1Networking & Internet 1Hardware & Electronics 1
2
You can't cURL a Border
Building a state machine for travel - tracking Schengen days, the 183-day rule for tax residency across countries, and visa thresholds when governments won't expose state.
3
I analysed 20 years of my chats
Importing 1.2 million messages from Telegram, VK, Instagram, Facebook, and Twitter into a structured Obsidian vault with local LLM inference - to measure how my friendships work with decay curves, vocabulary shifts, directional sentiment, and conflict rates.
4
Things I Learnt in 2020
For the past six months I have been sending out a weekly newsletter with things I learnt and read during the week. Some of those trivia are not trivial at all, so I decided to share the condensed crème de la crème of the Internet in this New Year special edition.
5
My phone replaced a brass plug
Porting a 2012 OpenCV paper to YOLOv8 and CoreML on iOS to score rifle shooting targets from a photo - replacing the brass-plug scoring gauge with on-device computer vision.
6
Designing software for things that rot
Building an iOS fermentation tracker with HACCP-style decision trees for home charcuterie, salami curing, and fermented foods - food safety without internet strangers.
7
The Whole App is a Blob
Building a Tamagotchi-style language learning iOS app with SwiftUI character animation - on drill design, motivation loops, and where Duolingo gets it wrong.
8
What I've learned sending proposals to conferences
This year I sent out quite a few proposals to the majority of mobile conferences in Europe. Some ignored me, the others replied with automated rejections. However, some accepted and it was fun. Here is what I've learned on the way.