How granular is configuration cache? If I build

:foo:assemble

and save CC, then build

:bar:assemble

and those two projects share numerous dependencies on other projects in the build, will there be any reuse of serialized configuration from the first command when running the second?

Not yet. Currently a CC entry is bound to the exact set of tasks you request to run. So even if you would execute

:foo:assemble :bar:assemble

and after that

:foo:assemble

nothing would be reused from CC.

The isolated projects feature builds on the CC and will add the fine-grained caching.

Parallel configuration and fine-grained caching are not applied to task execution. They are only applied to IDE sync.

https://docs.gradle.org/nightly/userguide/isolated_projects.html are those docs incorrect?

The docs are correct but that first sentence is missing a "yet". There's still some work to do to make those things work for task execution, but it will happen. The focus so far has been on making sync faster.

👍 is there an issue or roadmap item for isolated projects specific to task execution? These two existing items are pretty general, and the "Stable Isolated Projects" goal only mentions android studio sync https://github.com/gradle/build-tool-roadmap/issues/43 https://github.com/gradle/build-tool-roadmap/issues/76