# Pre-RFC: Testing a dependency features

**URL:** <https://internals.rust-lang.org/t/pre-rfc-testing-a-dependency-features/23545>\
**Category:** language design\
**Created:** [September 18, 2025, 4:52pm UTC](https://internals.rust-lang.org/t/pre-rfc-testing-a-dependency-features/23545 "2025-09-18T16:52:10Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![epage](https://sea2.discourse-cdn.com/flex002/user_avatar/internals.rust-lang.org/epage/32/3171_2.png) [@epage](https://internals.rust-lang.org/u/epage)\
**Post date:** [September 18, 2025, 5:03pm UTC](https://internals.rust-lang.org/t/pre-rfc-testing-a-dependency-features/23545/2 "2025-09-18T17:03:49Z")

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Related cargo issues:

- [Automatically activate a dependency if its used elsewhere in dependency graph · Issue #1555 · rust-lang/cargo · GitHub](https://github.com/rust-lang/cargo/issues/1555)
- [Managing the propagation of features across a large workspace is infeasible without tooling support · Issue #9094 · rust-lang/cargo · GitHub](https://github.com/rust-lang/cargo/issues/9094)

In particular, we should keep in mind [Managing the propagation of features across a large workspace is infeasible without tooling support · Issue #9094 · rust-lang/cargo · GitHub](https://github.com/rust-lang/cargo/issues/9094#issuecomment-1315121350)

I think more is needed to understanding the motivating use cases. In some situations, this is about cross-cutting functionality which might be better served by [Pre-RFC: Mutually-excusive, global features](https://internals.rust-lang.org/t/pre-rfc-mutually-excusive-global-features/19618).

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_[View the full topic](https://internals.rust-lang.org/t/pre-rfc-testing-a-dependency-features/23545)._