Publishing a KMP library commits you to every target you listed
Dropping a target in a minor release breaks consumers at resolution time.
kmp
41 posts
Adding a parameter with a default broke the ABI
Source compatibility and binary compatibility are different guarantees, and a default argument preserves only the first.
Seven modules, seven copies of the same Gradle block
Copy-pasted build config drifts silently per module. A convention plugin makes the shared part shared.
iosTest needs a booted simulator, and CI does not have one by default
The native test binary runs on a device, so a missing simulator reads like a toolchain problem.
Image loading is the least portable thing in your shared UI
Decode, cache and memory pressure are platform concerns, and the composable that hides them decides your scroll performance.
A feature flag read on four platforms needs one source of truth and four caches
Flags that differ per platform at the same moment produce bug reports nobody can reproduce.
A dependency that resolves in commonMain and only exists on Android
Gradle metadata decides which variant each target gets. A library with no native artifact fails at link, not at resolution.
Shared navigation has no back stack owner, and that is the hard part
Android has a system back gesture with an owner. iOS has a navigation controller. A shared back stack answers to both.
KSP runs once per target, and your generated code can disagree with itself
A processor sees one compilation at a time. Generating into commonMain is a race you win by accident.
There is no File in commonMain, and that is a feature
wasm has no filesystem and iOS has a sandbox with policy. An interface forces you to name what you need.
Hashing a password in shared code is the one thing you should not share
Each platform has a vetted crypto provider. A pure-Kotlin implementation has none of their review.
Throwing across the bridge loses your exception type
Swift sees NSError with a wrapped message, so a typed catch becomes a string match.