All Articles
Every Experiment Kept Landing on the Same Devices: Hash Choice and Salt Position, Measured Across a Million IDs
On-device experiment assignment looked fine in isolation, then collapsed the moment two experiments ran side by side. Here is what one million IDs revealed about four hash functions, why the culprit was the concatenation order rather than hash quality, and the implementation I settled on, with the measured numbers.
What Renovate may bump in an Expo app, and what it must never touch
Turning on automated dependency updates in a Rork-generated app also hands Renovate the 123 packages Expo SDK 57 pins. Measured on 2026-07-30, six of them sit a full major version behind npm latest. Here is how to generate the ignore list from the SDK instead of maintaining it by hand.
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 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.