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SkillsMP has collected 224 skills from maxrave-dev/kotlin-footguns. Open a skill to review its source and details.
Showing 40 of 224 collected skills.
Audit every native dependency for a slice on a CPU architecture before promising that target in a multiplatform desktop build — one missing native takes the whole target down at first use rather than at build time, so make the audit a repeatable command over…
Derive an automatic crossfade duration and a tempo/key match from how far apart two tracks are, the way a DJ would — halftime normalisation before comparing tempos, beat-quantised durations, a front-loaded ramp and quantised gain/speed steps. Use when an…
Import thousands of rows from a user-supplied file without the UI going dark or the batch dying halfway — chunk the writes and emit progress per chunk, reject a parse that yields nothing before touching the database, and filter incoming rows down to those…
A native library you bundle with a desktop app drags its own copy of a general-purpose base library along, that copy claims the shared-object name for the whole process the moment your native loads, and an unrelated platform API then fails with a…
Lay out a Kotlin Multiplatform app in layers that actually hold — a domain module carrying interfaces and models, repository implementations kept internal to the data module, and one module per external integration so a breaking service cannot spread — plus…
A Devanagari, Gurmukhi, or other diacritic-marked letter that looks like one glyph in the editor fails to compile as a `'x'` character literal with "Too many characters in a character literal," because it is a base letter plus a separate combining mark — two…
Render a composable off-screen into an ImageBitmap so a button can save or share it as a picture — a capture primitive ported into common code rather than pulled in as a platform-only dependency, a max-width ceiling standing in for a fixed output size,…
Rendering video frames from a native media engine in Compose Desktop without embedding a heavyweight AWT panel — publish finished frames as immutable snapshots on a StateFlow and draw them with a plain Image, convert off the UI thread, match the engine's…
Verifying a config-driven feature against the generated artifact instead of against the config, for formats that fail open and ignore unknown keys — the two-build A/B diff, the artifact fingerprint to grep for, and the CI assertion that keeps it from…
Packaging a JVM desktop app with a config-driven packager whose HOCON config silently ignores unknown keys — which keys bind at the app level versus a per-OS section versus a nested group, command-line key overrides, pinning the packaging JDK, and the…
Build a multiplatform preferences manager — the store instance produced per platform from nothing but a file path, one observing flow plus one suspend setter per key, and the interface declared in the domain layer so feature code never imports the storage…
A boolean that is a pure function of state already being collected gets stored as its own `mutableStateOf` anyway, seeded with a guess and corrected a frame later by a `LaunchedEffect` — so the first frame renders the guess, and later changing only the seed…
Embedding a native C media engine in a JVM desktop app — one handle per media item, a dedicated event-pump thread, pinning the output driver and creating the render context in the right order, confining every property write to the thread that also releases…
Suppress the "ended" playback state at a forwarding-player boundary while the underlying player is being replaced, so the media service is not torn down in the gap between one player finishing and the next starting. Use when background playback stops partway…
Swap the underlying player beneath a `ForwardingPlayer` at runtime while the media session and the UI keep one stable reference — re-attaching listeners and the video output, and answering the playlist questions a one-item timeline cannot. Use when…
The composable widget toolkit is not Compose with a different import — it has no aspect ratio, its weight is always 1 so an even split is the entire vocabulary, its corner radius only applies from API 31, and a widget always fills the launcher's cell so the…
A style or effect option is correctly hidden from a settings picker below some OS version or capability floor, yet the effect it names still shows up broken — flat, unblurred, or simply wrong — on a device that should never be able to select it, because the…
Move dependency injection from an annotation-processed compile-time framework (Hilt/Dagger) to the multiplatform runtime container (Koin) — the mechanical mapping for providers, view models and qualifiers, what happens to assisted injection, and the two…
A component that is committed to running but not yet running reports "not running", so anything that means intent must read the intent flag, not the observed one — and at a transition the intent flag must be waited for with a timeout rather than sampled…
Hand-writing a JVM binding for a C library with JNA (Java Native Access) — the open-flags option that means something else on Windows, structs read by raw offset, callbacks the binding holds weakly, search paths registered too late, and proving which file was…
Wiring view models through a runtime dependency-injection container without losing track of their lifetime — the service-locator base class and what it costs, annotation-based definitions that compile but register nothing, which store owner each accessor…
Wrap the multiplatform date-time library's instant-to-local-date-time conversions in a few named helpers — now, epoch converters, comparisons, a shifted-window helper and a relative "time ago" formatter — so call sites read as intent instead of ceremony.…
Build per-user listening or usage analytics entirely on-device — an append-only event table plus a denormalized per-contributor table that carries a copy of the timestamp, two completion thresholds instead of one, bare ids in events enriched to titles and…
Write a custom audio processor for a Media3/ExoPlayer audio pipeline — a filter, a fade, a gain stage — that is toggled at runtime and shared across several concurrent players. Use when a processor you added does nothing until the next track, when playback…
Playing a separate audio-only stream and video-only stream as ONE source on JVM desktop through the media engine's edit-list URL form — the desktop counterpart of a merging media source — including length-prefixed quoting of stream URLs and why a merged…
One `var xJob: Job?` field per concern, cancel-before-relaunch as an invariant at every launch site, and teardown writes wrapped so a cancellation cannot stop them halfway. Use when periodic updates arrive several times per tick, when stale results from a…
Producing a native shared library a JVM app can actually load and ship — why a prebuilt portable bundle usually is not a loadable library at all, building on the oldest base system you support, run-path choice, which libraries to deliberately leave out of the…
Decide whether a mid-size app needs an interactor or use-case tier at all, how a clean boundary survives without one (repository interfaces plus pure mapping functions), how to prove an absence rather than assume it, and the specific signal that says it is…
A now-playing artwork pager that both follows the player and drives it, without the two writing to each other in a loop — the in-progress-scroll flag covers programmatic animation as well as drags, the seek is dispatched from the settled page only, and the…
A tokenizer, spellchecker or analyzer needs a multi-megabyte dictionary that would bloat every install for a feature most users leave off — fetch it once, on opt-in, into a plain directory, and make every consumer ask the filesystem "am I ready" rather than…
Apply per-track loudness normalisation with the platform's loudness enhancer when each track gets its own player — re-creating the effect per track because it stays attached to one audio session, skipping it while a remote-playback session is active, and…
Persisting and restoring the playback position cheaply — a full queue save on lifecycle edges versus a light five-second position tick that rides an existing loop, skipping the save while the queue is being rebuilt, and snapshotting values before issuing…
A player's "current index" is exposed to the UI but freezes on track change or highlights the wrong row once shuffle is on, because the engine's timeline order and the shuffled play order are two different index spaces. Use when the now-playing marker in a…
Build a small real-time IIR filter in pure Kotlin from the audio-EQ-cookbook formulas — low-pass, high-pass, or a bank of peaking sections — with cascaded stages for a steeper slope, independent state per channel, neutral stages that keep the state size…
An envelope family for repository results — a remote wrapper, a local wrapper with a loading state, and a payload-free variant — plus the wrap-side and collect-side helpers that stop every view model from hand-writing the same branch, where the mapping from…
Set up one Room database shared across Android, JVM/desktop and iOS with an expect/actual builder per platform, a bundled SQLite driver chosen once at the injection site, and a per-architecture audit of the driver artifact. Use when adding Room to a Kotlin…
Keep a Room database upgradable after twenty-plus schema versions — declaring the whole graph of (from,to) edges instead of assuming users only ever hop one version, filling the gaps a generated migration cannot express, and recreating triggers idempotently…
Adding a "show pronunciation" or transliteration feature across many non-Latin scripts in a Kotlin Multiplatform module — without pulling in ICU — needs a per-script dispatch built on Unicode block ranges rather than a locale, one line at a time rather than…
Four small helpers worth carrying in a shared module, each with the one way it misleads — a symmetric set difference for diffing two id sets, a position index for constant-time lookups, a tolerant parse/serialize pair for timestamped tokens that returns null…
A story-style reel — a pager that advances itself on a per-card timer, with a segmented progress bar, tap zones to skip forward or back, and a press-and-hold that pauses it — where every card's data is computed once before the first frame instead of card by…