Hierarchy¶

The plugin replaces KGP's default hierarchy template with a minimal one: only the intermediate source sets the registered targets need. Why: Design.

Minimal template¶

Active targets	Intermediate source sets
one iOS leaf	none (target attaches to `commonMain`)
iOS (≥2 leaves)	`iosMain` only — no `appleMain`, no `nativeMain`
iOS + macOS	`appleMain` over `iosMain` + `macosMain` — no `nativeMain`
iOS + Linux	`nativeMain` over `iosMain` + `linuxMain` — no `appleMain`

The collapse rule: a group materializes a source set only when it merges ≥2 present children; a single-child group collapses away. If that drops a source dir your code needs, see Keeping intermediates.

On by default, applied automatically.

Opting out¶

Opt out when a module supplies its own applyHierarchyTemplate { … } — KGP's default applies again:

# kmp-targets.properties — global default (also accepted via -P, env, gradle.properties,
# local.properties — same precedence chain as kmptargets.targets)
kmptargets.hierarchyTemplate=false

// any module's build.gradle.kts — per-project override
kmpTargets { hierarchyTemplate.set(false) }

Precedence: project DSL > global key > built-in default (true).

Keeping intermediates¶

Codebases with actual implementations in intermediate source dirs (src/iosMain) break under the collapse: narrowing to a single iOS leaf (-Pkmptargets.targets=iosArm64) drops iosMain from the model and expect declarations stop resolving. No-collapse mode materializes a group whenever it has ≥1 present child, so iosMain survives:

# kmp-targets.properties — global default (same precedence chain as the other keys)
kmptargets.hierarchyCollapse=false

// any module's build.gradle.kts — per-project override; set BEFORE supports { }
kmpTargets {
    collapseHierarchy.set(false)
    supports { appleMobile }
}

Precedence mirrors hierarchyTemplate: project DSL > global key > built-in default (true, collapse).

Semantics:

Single-child chains materialize fully (nativeMain → appleMain → iosMain for one iOS leaf). The empty intermediates are harmless — no code, nothing to resolve.
Empty groups are still dropped; ungrouped leaves (jvm/android/web) still never form groups.
The knob never changes what registers — only which intermediate source sets materialize. It is a no-op when hierarchyTemplate resolves to false.

The pinned-intermediates sample is an appleMobile module with collapse off.

Renamed targets¶

KGP's hierarchy matchers (withJvm()) key off the platform type, not the target name — a renamed jvm target attaches to the minimal template exactly as a plain jvm would.