JetBrains has rolled out version 0.8.0 of its experimental build tool Amper, introducing long-awaited support for Compose Hot Reload, along with a set of new improvements aimed at Kotlin, Java, and multiplatform developers.

Real-Time Interface Updates for Compose Apps

The standout addition in Amper 0.8.0 is Compose Hot Reload, a feature that enables developers working on Compose Multiplatform applications to instantly view UI modifications. Instead of restarting an app each time a change is made, Amper automatically refreshes UI updates during development — drastically speeding up the design and debugging cycle.

Custom Kotlin Compiler Integration

This release also empowers experienced Kotlin users with more flexibility in their workflow. Developers can now manually select and test custom Kotlin compiler versions before future Amper releases. JetBrains notes that only compiler versions starting from 2.0.0 are compatible with this new configuration option, simplifying early testing and adoption of upcoming improvements in Kotlin.

Extended Platform Targets

Amper now includes support for JavaScript (js) and WebAssembly (wasmJs and wasmWasi) targets. Although these targets are still in their early stages, they lay the groundwork for broader multiplatform capabilities. JetBrains also simplified project module handling — the jvm/app and android/app modules now only use the src directory, and the @jvm qualifier is no longer valid in configuration files.

In addition, a new dedicated product type, jvm/lib, has been introduced for JVM-only libraries. This structure enhances clarity by explicitly conveying the intended library scope while maintaining all benefits of previous configurations.

Gradle Plugin Discontinued

JetBrains confirmed that Amper will no longer be distributed as a Gradle plugin. The 0.7.0 release marked the end of Gradle-based Amper versions, with the company now focusing on developing a new migration path for existing Gradle users.

Developer Experience Improvements

Other useful updates in version 0.8.0 include:

• Amper can now recognize the local Maven repository as a valid dependency source, allowing easier integration with locally built artifacts.
• When adding new folders in a module, developers can choose from several predefined directory templates depending on platform needs.
• A new CLI command, ./amper show dependencies, provides a full visualization of a module’s dependency graph.

Availability

Released on October 3, Amper 0.8.0 is available through JetBrains’ GitHub repository. Existing setups can be updated via the terminal using ./amper update. For the best experience with the tool’s latest features, developers are encouraged to use IntelliJ IDEA 2025.3 EAP or newer versions.

Amper remains in active development, aiming to simplify cross-platform building while giving developers greater control and responsiveness throughout the coding process.