Kotlin libraries

The coroutine runtime for Kotlin, providing structured concurrency, dispatchers, channels and Flow for asynchronous and reactive programming.

Ktor is JetBrains' asynchronous framework for HTTP servers and clients in Kotlin, built on coroutines with a plugin-based architecture.

Kotlin's official serialisation library, generating encoders at compile time with a compiler plugin — no reflection, and Multiplatform-compatible.

Exposed is JetBrains' SQL library for Kotlin, offering both a typed DSL that mirrors SQL and a lightweight DAO layer.

Koin is a pragmatic dependency injection framework for Kotlin using a DSL, with no code generation, no reflection and no annotation processing.

MockK is a mocking library built for Kotlin, supporting coroutines, final classes, objects, extension functions and constructor mocking.

Kotest is a Kotlin testing framework with multiple spec styles, a large assertion library, property-based testing and data-driven test support.

Arrow brings typed functional programming to Kotlin: Either and Option for errors, typed error DSLs, optics, and resource-safe operations.

detekt is a static analysis tool for Kotlin, detecting code smells, complexity problems, potential bugs and style violations, with baseline support for existing codebases.

The official Kotlin Multiplatform date and time library, providing Instant, LocalDate, LocalDateTime and time zone handling across JVM, Android, iOS and JS.

Jetpack Compose is Android's declarative UI toolkit, describing interfaces as composable functions of state rather than as mutable view hierarchies.

Room is Android's persistence library, providing a typed abstraction over SQLite with compile-time query verification and Flow observation.

Hilt is Android's recommended dependency injection framework, built on Dagger with a simplified API and Android lifecycle-aware components.

SQLDelight generates typesafe Kotlin APIs from .sq files containing plain SQL, working across Android, JVM, iOS and JS.

Coil is an image loading library for Android and Compose Multiplatform, built on coroutines with automatic memory and disk caching.

Okio is a library for I/O in Kotlin and Java, offering buffered sources and sinks, a multiplatform filesystem abstraction and efficient byte handling.

Moshi is a JSON library for Kotlin and Java from Square, with a code-generating adapter option that respects Kotlin's null safety and default values.

Turbine is a small testing library for Kotlin Flows, providing a clear API for asserting on emissions, completion and errors.

ktlint is an anti-bikeshedding linter and formatter for Kotlin that enforces the official style guide with essentially no configuration.

JetBrains' extension of Jetpack Compose to desktop, iOS and web, letting one declarative UI codebase target several platforms.

Voyager is a navigation library for Compose Multiplatform with type-safe screens, nested navigators, tabs and integrated screen-scoped models.

A Kotlin Multiplatform key-value storage library wrapping SharedPreferences on Android, NSUserDefaults on Apple platforms and equivalents elsewhere.

Kermit is a Kotlin Multiplatform logging library from Touchlab that routes to Logcat on Android, os_log on Apple platforms and stdout elsewhere.

Ktorm is a lightweight Kotlin ORM with a strongly-typed DSL whose operators mirror SQL closely, plus an optional entity-object layer.

Store from Dropbox coordinates network fetching and local caching behind one API, providing single-source-of-truth data loading for Kotlin applications.

Paging 3 loads large datasets incrementally on Android, handling page requests, retries, placeholders and Compose integration.

WorkManager schedules deferrable, guaranteed background work on Android, surviving process death and reboots while respecting battery restrictions.

kotlinx-cli is JetBrains' Multiplatform command-line argument parser, with typed options, subcommands and generated help.