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499 exclusive articlesThe same wallpaper appeared twice in my catalog — measuring perceptual hash thresholds across 324 images
Four approaches to image catalog deduplication measured end to end: SHA-256, dHash, a hue signature, and a block signature. dHash alone scored 0.9% precision. Here is why perceptual hashes collapse on smooth images, and how the ground truth turned out to be the thing that was wrong.
Counting what prebuild --clean will erase before you upgrade to Expo SDK 57
A raw diff between two generated ios/ trees showed 649 changed lines; only 3 were real edits. How to count what prebuild --clean erases, and move it into a config plugin.
When to Raise Your Minimum iOS Version — Count Leftover Branches, Not User Percentages
Judging a minimum OS bump by usage share produces the same answer every year, so the decision never happens. Here is the annotation convention, the sweep script that counts how many iOS and Android branches each candidate floor would retire, and what to watch for 30 days after.
What Filtering Out Prerelease OS Devices Cost Me — Separating Telemetry Tracks Instead of Dropping Them
Filtering prerelease OS devices out of telemetry left me with no warning signs on GA day. Here is the rebuild: an os_track dimension, a remote GA baseline, split alert thresholds, and a release gate that separates blockers from fixes.
Collapsing Duplicate Requests Into One: A Reference-Counted Single-Flight Layer
When several components fire the same API call at launch, you get a burst of identical requests. Here is a single-flight layer that shares one in-flight promise instead: how to build the key that decides the folding, the trap of handing out a failed promise forever, the trap of one caller's abort cancelling everyone, and the test that keeps it all from regressing, with the real network numbers alongside.
Resolving App Config in Three Layers: Merging Defaults, User, and Remote With Bounded Overrides
A single type-safe layer that merges compiled defaults, user preferences, and remote config. So a broken remote value never takes your app down, each key gets its own override strength, plus schema validation and range clamping, built from a real production incident.
When Bumping Push to Three a Day Cut Next-Week Returns — Field Notes on Measuring Notification Frequency by D7 Retention and Opt-Out Rate
The assumption that heavier push means more returns was quietly eroding my D7 retention. These are field notes on re-measuring notification frequency by install-cohort D7 and opt-out rate, and walking from three a day back to one.
Sunsetting an App Well — Designing the Path from Update Freeze to Full Shutdown
What to do with an app whose revenue no longer covers its server bill. A three-stage decision table, a CDN-based sunset flag with TypeScript implementation, a data export path, and the practical order for winding down auto-renewable subscriptions.
When Rork Max's Two-Click Submit Stalls, Tell Which Layer Broke
Rork Max's one-click install and two-click submit fold the complexity of iOS shipping into four hidden layers. When the abstraction leaks and your submission stalls, this map helps you tell which layer failed and fix it yourself.
Stop Spinning Up a Separate Server: Colocate Your Backend With Expo Router API Routes
Standing up yet another Worker just to receive a RevenueCat webhook gets old fast. Expo Router API Routes let you put the backend inside the same repo as your app. Here is the implementation, from signature verification to picking a deployment target.
The Generated Screen That Quietly Jams at AX5 and in German — Putting Layout Resilience Checks on Rork Max SwiftUI
A record of running every Rork Max generated SwiftUI screen through pseudolocalization and the largest text size to find exactly where it jams. Covers when to reach for ViewThatFits, ScaledMetric and layoutPriority, plus the snapshot checks that catch regressions every time you regenerate.
Your AR Furniture Is Gone by Morning — Persisting Placements with ARWorldMap
AR apps generated by Rork Max lose every placed object on relaunch. Here is the design that fixes it: when to save an ARWorldMap, how to encode custom anchors, how to handle the relocalization wait, and what to do when relocalization simply never lands.
Shipping Notifications Without Asking First — Provisional Authorization in Rork Apps, and the Expo Snippet That Quietly Undoes It
iOS lets you start delivering notifications with no permission dialog at all, via provisional authorization. The catch: expo-notifications reports granted as false for provisional devices, so the registration snippet in Expo's own docs re-requests permission and fires the very dialog you were avoiding. Here's why granted lies, a hook that models authorization as five states, how to write notifications for quiet delivery, when to ask for the upgrade, and how to keep provisional out of your CTR.
The Three-Minute Video That Kept Failing — Moving Rork's Gemini Uploads Off the Worker
How I rerouted video uploads to the Gemini Files API from a Cloudflare Workers relay to a direct device-to-Google path — why the 128MB isolate limit breaks the relay, how to hand out a resumable upload URL without leaking your API key, what Expo SDK 54 broke on the device side, and how the 20GB project ceiling and media resolution decide the bill.
The Update That Failed Because a Profile Expired Three Months Ago
Apple signing assets expire quietly and nothing tells you. Here is how to count the days left with the App Store Connect API and put the audit on a weekly Cloudflare Workers cron.
Killing the Export Compliance Prompt in Rork Builds for Good
Every Rork and Rork Max build lands in App Store Connect with a Missing Compliance warning. Here is how to decide whether you qualify for the exemption, and how to set it once in app.json or Info.plist so the question never returns.
Placing Native Ads in a Masonry Wallpaper Grid: Designing the Lifetime of an Ad Cell
One native ad in a masonry gallery pushed memory from 180 MB to 420 MB over twenty minutes of scrolling. Here is why cell recycling and ad object lifetime never line up, the pool-based implementation that fixed it, and how I picked the insertion interval from measured numbers.
Regenerable Zones in Rork Max Code: Keeping the Freedom to Rebuild
Generated code carries an invisible asset: the option to throw it away and rebuild it. Every hand edit quietly expires that option. Here is how I track it with a ledger and CI checks across six live apps.
Test Generated Purchase Code Before You Touch Sandbox — Automating Refunds, Expiration, and Failures with SKTestSession
Rork Max generates StoreKit 2 code that proves people can buy. It does not prove refunds, expiration, or failed purchases are handled. Here is how to cover those paths with SKTestSession before you ever open Sandbox.
The Comma That Fell to the Start of a Line: Rork, Quote Cards, and Japanese Line Breaking
React Native's Text component does not guarantee Japanese line-breaking rules. Here are the violation rates I measured, a WORD JOINER implementation that survives copy and VoiceOver, an onTextLayout audit harness, and how Rork Max (SwiftUI) differs.
On-Device Image Classification: TFLite on React Native or Core ML on Rork Max — How I Chose After Building Both
Adding on-device image classification means choosing between TFLite on React Native and Core ML on Rork Max. I built the same feature both ways, measured the end-to-end breakdown, and worked out what the decision actually hinges on.
Half the Bytes, the Same Wait: What AVIF Actually Cost My Wallpaper Apps
Switching to AVIF cut my transfer bill in half and did nothing for perceived speed. Here is the transfer-versus-decode breakdown, the Accept-negotiation trade-off, per-device fallback tiers, and the staged migration order that finally worked across six apps.
My Rork sleep timer faded out on time — but the sound didn't
Rork writes sleep-timer fades against the wall clock with setInterval. The numbers say 30 minutes, but the real audio fades early or cuts out abruptly. Here is how to drive the fade from the actual playback position, why a logarithmic curve sounds natural, and the honest limit of JS fades when the screen is locked.
Long-Press Context Menus for a Gallery Item in a Rork Expo App
Long-pressing a wallpaper card does nothing, yet iOS users expect a preview and a menu. From why Pressable alone falls short, to a native context menu with zeego, resolving the scroll-vs-long-press conflict, wiring up save and share, and a custom overlay fallback for Android — all with working code.
Designing Seams That Survive AI Regeneration in Rork
Every follow-up prompt to Rork can quietly wipe out logic you wrote by hand. Protecting it with prompts is a patch, not a fix. Here is how to separate generated code from code you own, and draw a boundary that regeneration cannot reach, with working Zustand and service-layer examples.
Adding a Single Zod Validation Boundary to Rork's Generated Fetch Code
The network code Rork generates implicitly trusts the shape of the response. When the API shifts, the screen quietly goes blank. Here is how to slip a single Zod parse layer between the generated UI and the network to make failures predictable, with numbers from real operation.
postMessage Is Fire-and-Forget — Designing a Correlated Request/Response Bridge Between a WebView and React Native
postMessage between a WebView and React Native is one-way, so you never learn whether the work you asked for actually succeeded. Here is a typed request/response bridge, with correlation IDs and timeouts, built in working TypeScript.
When "{n} items" Breaks Across Languages — Designing Quantity Strings with CLDR Plural Categories and Intl.PluralRules
The assumption that one is singular and everything else is plural falls apart in Russian and Arabic. Here is how to hold the CLDR plural categories as a map and render quantities correctly with Intl.PluralRules and i18next, drawn from localizing an indie wallpaper app into sixteen languages.
Your Detox and Maestro E2E Suite Was All Green — but the Retries Were Hiding a Flaky Test That Crashed in Production
Your E2E suite is green, yet production still crashes. The culprit: auto-retries quietly swallowing flaky failures. Field notes on measuring per-test flake rate, quarantining, and keeping only real failures as release gates.
Losing HealthKit Data on Incremental Sync — Designing HKQueryAnchor Persistence
When step or sleep data double-counts or goes missing on incremental HealthKit sync, the root cause is usually HKQueryAnchor persistence. Here is a working Swift design that handles newAnchor and deletedObjects correctly and stays consistent across reinstalls and background updates.