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 React core team.
The "RFC" (request for comments) process is intended to provide a consistent and controlled path for new features to enter the project.
Contributor License Agreement (CLA)
In order to accept your pull request, we need you to submit a CLA. You only need to do this once, so if you've done this for another Facebook open source project, you're good to go. If you are submitting a pull request for the first time, just let us know that you have completed the CLA and we can cross-check with your GitHub username.
When to follow this process
You should consider using this process if you intend to make "substantial" changes to React or its documentation. Some examples that would benefit from an RFC are:
- A new feature that creates new API surface area, and would require a feature flag if introduced.
- The removal of features that already shipped as part of the release channel.
- The introduction of new idiomatic usage or conventions, even if they do not include code changes to React itself.
Some changes do not require an RFC:
- Rephrasing, reorganizing or refactoring
- Addition or removal of warnings
- Additions that strictly improve objective, numerical quality criteria (speedup, better browser support)
- Additions only likely to be noticed by other implementors-of-React, invisible to users-of-React.
What to expect
It is hard to write an RFC that would get accepted. Nevertheless, this shouldn't discourage you from writing one.
React has a very limited API surface area, and each feature needs to work seamlessly with all other features. Even among the team members who work on React full time every day, ramping up and gaining enough context to write a good RFC takes more than a year.
In practice, React RFCs serve two purposes:
React Team RFCs are submitted by React Team members after extensive (sometimes, multi-month or multi-year) design, discussion, and experimentation. In practice, they comprise the majority of the RFCs that got merged so far. The purpose of these RFCs is to preview the design for the community and to provide an opportunity for feedback. We read every comment on the RFCs we publish, respond to questions, and sometimes incorporate the feedback into the proposal. Since our time is limited, we don't tend to write an RFC for a React feature unless we're very confident that it fits the design. Although it might look like most React Team RFCs easily get accepted, in practice it's because 98% of ideas were left on the cutting room floor. The remaining 2% that we feel very confident and have team consensus on about are the ones that we announce as RFCs for community feedback.
Community RFCs can be submitted by anyone. In practice, most community RFCs do not get merged. The most common reasons we reject an RFC is that it has significant design gaps or flaws, does not work cohesively with all the other features, or does not fall into our view of the scope of React. However, getting merged is not the only success criteria for an RFC. Even when the API design does not match the direction we'd like to take, we find RFC discussions very valuable for research and inspiration. We don't always review community RFCs in a timely manner, but whenever we start work on a related area, we check the RFCs in that area, and review the use cases and concerns that the community members have posted. When you send an RFC, your primary goal should not be necessarily to get it merged into React as is, but to generate a rich discussion with the community members. If your proposal later becomes accepted, that's great. But even if it doesn't, it won't be in vain. The resulting discussion often informs the next proposal in the same problem space, whether it comes from the community or from the React Team. Many library authors are reading the discussions, so RFCs often lead to community experimentation and userland solutions.
We apply the same level of rigour both to React Team RFCs and Community RFCs. The primary difference between them is in the design phase: React Team RFCs tend to be submitted at the end of the design process whereas the Community RFCs tend to be submitted at the beginning as a way to kickstart it.
What the process is
In short, to get a major feature added to React, one usually first gets 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 into React.
- Fork the RFC repo http://github.com/reactjs/rfcs
text/0000-my-feature.md(where 'my-feature' is descriptive. Don't assign an RFC number yet).
- Fill in the RFC. Put care into the details: RFCs that do not present convincing motivation, demonstrate understanding of the impact of the design, or are disingenuous about the drawbacks or alternatives tend to be poorly-received.
- Submit a pull request. As a pull request the RFC will receive design feedback from the larger community, and the author should be prepared to revise it in response.
- Build consensus and integrate feedback. RFCs that have broad support are much more likely to make progress than those that don't receive any comments.
- Eventually, the team will decide whether the RFC is a candidate for inclusion in React. Note that a team review may take a long time, and we suggest that you ask members of the community to review it first.
- RFCs that are candidates for inclusion in React will enter a "final comment period" lasting 3 calendar days. The beginning of this period will be signaled with a comment and tag on the RFCs pull request.
- An RFC can be modified based upon feedback from the team and community. Significant modifications may trigger a new final comment period.
- An RFC may be rejected by the team after public discussion has settled and comments have been made summarizing the rationale for rejection. A member of the team should then close the RFCs associated pull request.
- An RFC may be accepted at the close of its final comment period. A team member will merge the RFCs associated pull request, at which point the RFC will become 'active'.
The RFC lifecycle
Once an RFC becomes active, then authors may implement it and submit the feature as a pull request to the React repo. Becoming 'active' is not a rubber stamp, and in particular still does not mean the feature will ultimately be merged; it does mean that the core team has agreed to it in principle and are amenable to merging it.
Furthermore, the fact that a given RFC has been accepted and is 'active' implies nothing about what priority is assigned to its implementation, nor whether anybody is currently working on it.
Modifications to active RFCs can be done in followup PRs. We strive to write each RFC in a manner that it will reflect the final design of the feature; but the nature of the process means that we cannot expect every merged RFC to actually reflect what the end result will be at the time of the next major release; therefore we try to keep each RFC document somewhat in sync with the language feature as planned, tracking such changes via followup pull requests to the document.
Implementing an RFC
The author of an RFC is not obligated to implement it. Of course, the RFC author (like any other developer) is welcome to post an implementation for review after the RFC has been accepted.
If you are interested in working on the implementation for an 'active' RFC, but cannot determine if someone else is already working on it, feel free to ask (e.g. by leaving a comment on the associated issue).
Currently, the React Team cannot commit to reviewing RFCs in a timely manner. When you submit an RFC, your primary goal should be to solicit community feedback and generate a rich discussion. The React Team re-evaluates the current list of projects and priorities every several months. Even if an RFC is well-designed, we often can't commit to integrating it right away. However, we find it very valuable to revisit the open RFCs every few months, and see if anything catches our eye. Whenever we start working on a new problem space, we also make sure to check for prior work and discussion in any related RFCs, and engage with them.
We read all RFCs within a few weeks of submission. If we think the design fits React well, and if we're ready to evaluate it, we will try to review it sooner. If we're hesitant about the design or if we don't have enough information to evaluate it, we will leave it open until it receives enough community feedback. We recognize it is frustrating to not receive a timely review, but you can be sure that none of the work you put into an RFC is in vain.
React's RFC process owes its inspiration to the Yarn RFC process, Rust RFC process, and Ember RFC process.
We've changed it in the past in response to feedback, and we're open to changing it again if needed.