[rust-dev] RFC: Updated RFC process
banderson at mozilla.com
Tue Mar 11 18:11:48 PDT 2014
The freewheeling way that we add new features to Rust has been good for
early development, but for Rust to become a mature platform we need to
develop some more self-discipline when it comes to changing the system.
So this is a proposed modification to our current RFC process to make it
a more integral part of the overall development process, and one that is
followed consistently to introduce features to Rust.
Some improvements I would like this to bring over the current process
* Discourage unactionable or vague RFCs
* Ensure that all serious RFCs are considered equally
* Those with a stake in Rust's development should feel confident they
understand why new features are being merged
Below is the proposed change to the RFC process. Please read and
comment. Assuming the feedback is positive I'll update the wiki with
Many changes, including bug fixes and documentation improvements can be
implemented and reviewed via the normal GitHub pull request workflow.
Some changes though are "substantial", and we ask that these be put
through a bit of a design process and produce a consensus among the Rust
community and the [core team].
The "RFC" (request for comments process) is intended to provide a
consistent and controlled path for new features to enter the language
and standard libraries, so that all stakeholders can be confident about
the direction the language is evolving in.
## When you need to follow this process
You need to follow this process if you intend to make "substantial"
changes to the Rust distribution. What constitutes a "substantial"
change is evolving based on community norms, but may include the following.
- Any semantic or syntactic change to the language that is not a bugfix.
- Changes to the interface between the compiler and libraries,
including lang items and intrinsics.
- Additions to `std`
Some changes do not require an RFC:
- Rephrasing, reorganizing, refactoring, or otherwise "changing shape
does not change meaning".
- Additions that strictly improve objective, numerical quality
criteria (warning removal, speedup, better platform coverage, more
parallelism, trap more errors, etc.)
- Additions only likely to be _noticed by_ other developers-of-rust,
invisible to users-of-rust.
If you submit a pull request to implement a new feature without going
through the RFC process, it may be closed with a polite request to
submit an RFC first.
## What the process is
In short, to get a major feature added to Rust, one must first get the
RFC merged into the RFC repo as a markdown file. At that point the RFC
is 'active' and may be implemented with the goal of eventual inclusion
* Fork the RFC repo http://github.com/rust-lang/rfcs
* Copy `0000-template.md` to `active/0000-my-feature.md` (where
'my-feature' is descriptive. don't assign an RFC number yet).
* Fill in the RFC
* Submit a pull request. The pull request is the time to get review of
the design from the larger community.
* Build consensus and integrate feedback. RFCs that have broad support
are much more likely to make progress than those that don't receive any
* Eventually, somebody on the [core team] will either accept the RFC by
merging the pull request and assigning the RFC a number, at which point
the RFC is 'active', or reject it by closing the pull request.
Once an RFC becomes active then authors may implement it and submit the
feature as a pull request to the Rust repo. An 'active' is not a rubber
stamp, and in particular still does not mean the feature will ultimately
be merged; it does mean that in principle all the major stakeholders
have agreed to the feature and are amenable to merging it.
Modifications to active RFC's can be done in followup PR's. An RFC that
makes it through the entire process to implementation is considered
'complete' and is moved to the 'complete' folder; an RFC that fails
after becoming active is 'inactive' and moves to the 'inactive' folder.
### Help this is all too informal!
The process is intended to be as lightweight as reasonable for the
present circumstances. As usual, we are trying to let the process be
driven by consensus and community norms, not impose more structure than
[core team]: https://github.com/mozilla/rust/wiki/Note-core-team
More information about the Rust-dev