Kotlin Tooling Immutable Collections 0 5 X Migration

This handles the mechanical rename churn when you upgrade kotlinx.collections.immutable from 0.3.x or 0.4.x to 0.5.x, where every copy-returning method on PersistentList, PersistentMap, and friends got participial names per KEEP-0459 (add becomes adding, removeAt becomes removingAt, put becomes putting). It's compiler-driven: bump the version, recompile, and apply the rename each deprecation warning names. The guide is careful about what not to touch,mutable collections and builder types keep the old names, so you trust the compiler warnings instead of find-replacing blindly. It also covers custom implementers that need to move their overrides to the new names. Narrow but thorough if you're stuck with a few hundred call sites to fix.

skills.sh installs: 1.2K
GitHub stars: 1.1K
last updated: Jun 8, 2026

View on GitHub

Install

$ npx -y skills add kotlin/kotlin-agent-skills --skill kotlin-tooling-immutable-collections-0-5-x-migration --agent claude-code

Installs into .claude/skills of the current project.

Files

kotlinx.collections.immutable 0.5.x Migration

The 0.5.x line renames every copy-returning method on the persistent collections to a participial form (per KEEP-0459) and deprecates the old names at WARNING level with a ReplaceWith hint. Migrating is a mechanical, binary-compatible, semantics-preserving call-site rename — same parameters, order, and return type; only the name changes.

Drive it from the compiler: bump the version, recompile, and fix each deprecation warning — the warning names the replacement. Source of truth: 0.5.0-MIGRATION.md.

When it applies

Check the version the project currently uses:

0.3.x or 0.4.x (any pre-0.5.0) → run the migration below.
On 0.5.x but not the latest → set the version to the latest 0.5.x and stop. All 0.5.x releases share the same renames, so a within-line bump adds no new deprecations and needs no recompile.
On the latest 0.5.x, or on 0.6.x and later → nothing to do.