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SkillsMP has collected 224 skills from maxrave-dev/kotlin-footguns. Open a skill to review its source and details.
maxrave-dev/kotlin-footgunsShowing 40 of 224 collected skills.
Give items with no artwork a cover of their own by hashing the title into a stable gradient and packaging it, plus measured text and a badge, as a custom Painter you can hand straight to an image loader's placeholder, error and fallback slots — covering what…
Per-item pipelines that key on the item id with distinctUntilChangedBy, cancel the previous item's in-flight work before starting the next, and reset the visible state before filling it — so nothing from the previous item can appear under the new one. Use…
One suspend persistence body driven two ways — blocking on the shutdown path, where the write must complete before the scope dies, and fire-and-forget on periodic ticks — instead of two copies that drift apart. Use when saved state is correct while the app…
A UI-facing track list and the playback engine's timeline both hold the queue, so the UI list is re-derived from the engine timeline by media id after every engine-side change, refused when the sizes disagree, and mutated on both sides for user reorders. Use…
Give a model a canonical empty instance on its companion object so its holders can declare the field non-null, instead of threading a nullable through every layer. Covers when this genuinely removes a whole family of null checks and when it only adds a second…
Carry locally sorted and shuffled paging through the same token slot a remote API uses, by prefixing the token with a mode tag and encoding a cursor after it — and reject an unrecognised prefix loudly, because a silently ignored token leaves the pager stuck…
One StateFlow holds a growing playback queue but has two write paths on purpose — a full setter that resets derived snapshots, and continuation appends that write the backing field directly so those snapshots survive. Use when a feature keyed on "where the…
Reading a type marker the remote source declares for itself — normalizing before every comparison because locally stored rows from older app versions hold labels the app invented, treating null as "the source did not say" rather than as a default, exposing an…
Clamp long text to a few lines with a more/less affordance driven by measured overflow instead of a character count, and make timestamps or URLs inside the same text tappable. Use when "more" shows on text that already fits, never shows on text that does not,…
Ship one codebase in two forms — a full build carrying a proprietary or credentialed integration and an open build carrying a no-op stub — using twin modules with an identical public API selected by a Gradle property rather than product flavors, which do not…
The gesture and chrome layers of a fullscreen video screen — tap anywhere to toggle the controls, double-tap either half to seek, an auto-hide timer that every interaction postpones, and a picture-in-picture (PiP) guard that removes both layers. Use when…
One reusable helper that reads an entire table through a (limit, offset) data-access function in a bounded loop, stopping on the first short page — plus when reading everything is legitimate (export, backup, bulk mapping) and the smell that means you needed a…
Structure a GitHub Actions release pipeline for a multiplatform desktop app so one Linux runner cross-builds every platform's artifacts and a second, tiny macOS job does only the one step that genuinely requires macOS — with artifact handoff between them and…
Diagnosing Gradle failures of the form "cannot mutate a configuration after its child configuration was resolved" — why the message names the configuration you touched rather than the plugin that resolved it, how to bisect plugins against a minimal working…
Keep the start conditions of a feature that fires from two entry points — typically a polling loop and an end-of-item callback — identical on both paths, because a condition added to only one of them is dead code that produces no error, no log and no crash.…
Judge and reduce a desktop JVM application's memory honestly — read the heap-to-footprint ratio rather than the resident figure, run the one experiment that separates a leak from an allocator holding idle pages, and understand why per-thread allocator arenas…
Resolve two extension functions that differ only in their generic receiver's type argument and so compile to a single JVM method, using @JvmName on one of them. Covers what the annotation changes, why it beats renaming the Kotlin function, and what non-Kotlin…
Consume a git submodule as a set of Gradle modules in a multiplatform repo — mapping its nested directories onto flat project paths, making the recursive clone a hard prerequisite instead of tribal knowledge, and enabling submodules in every…
Settings-file patterns for a many-module Kotlin Multiplatform repo — mapping deeply nested in-repo directories onto flat Gradle project paths, turning on typesafe project accessors and knowing how they mangle names, declaring repositories in the two places…
Decode named, hexadecimal and decimal character entities in shared multiplatform code, where the platform's own markup helpers are unavailable. Covers the named table, the two numeric passes, the range check that keeps an out-of-range code point from ending…
Put one small logging object in the shared module between every call site and the logging library, so a chatty subsystem can be silenced in one line and the library can be replaced without touching call sites. Covers the muted-tag set, a level-as-a-value enum…
Split one Kotlin Multiplatform UI module into a shared app LIBRARY plus thin per-platform launcher modules — an Android application module that only packages, and a JVM/desktop module that owns main() and hands off to a public function in the library. Reach…
A multiplatform HTTP stack where one expect/actual hands back the engine and each integration builds its own client from it — an instrumented client for API calls next to a deliberately bare one for bulk downloads, content negotiation registered per format,…
Building a swipeable now-playing page whose layers — a colour backdrop, a full-bleed looping video or image, and a centred square cover — all belong to one pager, with per-page colours taken from the bitmap that page actually painted and a scrim spanning the…
A complete drag-to-reorder state holder for a lazily composed Compose list — pointer offset accumulation, target-index math over the visible window, how the lift animation and the built-in item placement animation must not overlap, edge auto-scroll as a delta…
Four small lazy-list utilities worth carrying between apps — scroll-direction as derived state, centre-an-item scrolling that waits a frame before measuring, an item's visible percentage, and a lookup into the visible window — with the trap each one hides.…
Match a string against a candidate list with a two-row edit-distance loop and no dependency, so the matcher lives in shared multiplatform code. Covers the two-row memory shape, normalizing before comparing, a similarity threshold that refuses rather than…
Matching a machine-generated id inside a text or JSON column with LIKE — why `_` and `%` in the id silently widen the match, how to escape them with nested replace() plus an explicit ESCAPE character, and why the id must be matched as a quoted token rather…
Logging out must reset every setting that depended on being logged in, at the logout choke point itself — otherwise a gated switch stays on for a service you are no longer authenticated to and silently no-ops forever, or errors on every tick. Use when a…
Strip the `._*` companion files that macOS archiving writes beside files carrying extended attributes, after unpacking anything into a macOS app bundle and before the bundle is signed, because the signer seals those companions as ordinary bundle members and…
Declaring a Launch Services environment dictionary (`LSEnvironment`) in a packaged macOS app's property list pins the process `PATH` to the four bare system directories, so every external process the app spawns loses everything installed elsewhere. Use before…
Render one heterogeneous list with one composable by tagging unrelated classes with an empty interface, plus a nested enum each implementor answers where the renderer has to branch. Covers when a tag beats a sealed hierarchy, the exhaustiveness you give up in…
Put every conversion between transport payloads, domain models and persistence rows in dedicated files of pure extension functions — one direction per function, no suspending work, no logging, nothing else in the file — and keep the layer honest with a grep.…
An empty or pass-through platform implementation in a multiplatform project means nobody wrote it, not that the platform cannot do it — check the dependency's resolved variants and the source set that declares it before telling anyone a feature is impossible…
Deliver a returning auth callback's token straight to session state and let the login screen close itself by observing the stored session — routing the token through navigation pushes a second login screen and the post-login close peels the wrong one. Use…
Map a sectioned API response as a list of (title, items) in the order it arrived, never by reading result[0] and result[1] into named fields — a signed-in account is recorded here as getting an extra section pushed in front, and any such shift mislabels every…
Build a browse tile whose cover art is tilted and runs off the clipped corner — the modifier order that makes the diagonal a cut rather than a pasted square, the rotated bounding-box growth that decides how much room siblings must leave, and why a non-square…
Splitting one file into N byte-range requests issued in parallel over a bare HTTP client, each chunk to its own temp file, merged in order, with progress reported through a channel-backed flow — plus when ranges are actually safe, how big a chunk should be,…
Build a periodic notifier that never misses an item when a run is delayed, and whose only way to repeat one is a kill inside a single narrow window. Covers keeping the "already handled" record in the database rather than in the worker, scanning a time window…
One generic "load this item and start playing" function normalizes several item types into a single internal shape, routes the queue-seeding strategy off a discriminator, and gates every pre-enqueue policy at that one place. Use when playback can start from…