JetBrains Retires Amper, Folds It Into Kotlin Toolchain as the New Unified Build Entry Point
Kotlin's build tooling has been a drag on adoption outside Android, with Gradle's complexity and IDE/CLI inconsistencies burning engineering time. A single, declarative toolchain that works identically everywhere lowers the barrier for multiplatform projects and makes Kotlin viable for backend and native work without Gradle expertise.
Kotlin Toolchain 0.11 marks the end of Amper as a separate tool and its rebirth as the official unified entry point for the Kotlin ecosystem. The `amper` command is gone, replaced entirely by `kotlin`, which now handles project creation, building, running, testing, and publishing through a single interface. This release adds Maven Central publishing for JVM libraries, handling sources jars, PGP signing, and POM metadata automatically from a declarative `module.yaml` file. Cinterop support is also improved, with the toolchain generating C library bindings from `.def` files during IDE sync.
The shift addresses a long-standing fragmentation problem: Kotlin projects currently require juggling the compiler, Gradle, multiple plugins, and platform-specific configurations. By converging these into one tool, JetBrains aims to make the engineering experience match the language's modernity. IDE and CLI behavior are now aligned at the module level, eliminating the classic 'works in terminal, red in IDE' failures that plague Gradle-based projects. Plugin development also gets new capabilities, including quality checks, custom commands, and unified declarations for generated sources.
Underneath the feature list is a strategic pivot. JetBrains is no longer trying to improve the Gradle experience; it is building a complete toolchain that can be statically analyzed by IDEs, CI systems, and AI agents. YAML configuration replaces executable Gradle scripts, making project structure machine-readable. While Gradle will persist in existing projects, its visibility in new Kotlin-first and KMP-first work will steadily shrink.
JetBrains is no longer content to be a language vendor dependent on Gradle; it is building a full platform toolchain that controls the entire developer workflow from creation to publication.
The move from 'improving Gradle' to 'replacing the Gradle entry point' signals that JetBrains sees Gradle's executable-script model as fundamentally incompatible with reliable IDE support and AI tooling.
Declarative YAML configuration is easier for machines to parse than Turing-complete build scripts, which positions Kotlin Toolchain as an AI-friendly build system before most ecosystems have one.
Aligning IDE and CLI behavior at the module level attacks one of the most persistent and costly pain points in JVM development: the divergence between what the editor shows and what actually builds.
KMP library publishing being absent from this release is a significant gap; until it ships, the toolchain cannot serve the multiplatform use case that Kotlin is most aggressively pushing.
The plugin extension points for checks, commands, and generated outputs suggest JetBrains intends the toolchain to be extensible enough to absorb tasks currently handled by Gradle plugins.