According to the TC39 process document, to advance from Stage 2 to Stage 3, reviewers and the editor group must sign off on the spec text. This document describes the Stage 3 review process.
Reviewers for Stage 3 volunteer as such in TC39 meetings when discussing a proposal. If the proposal is ready, the champion can ask the committee for reviewers at the same meeting as it advances to Stage 2. Sizable proposals are encouraged to have multiple reviewers. Different reviewers can provide different perspectives.
Reviewer feedback is tracked in a GitHub issue in the proposal repository (example). It may also be useful to send out a reminder email ahead of the meeting to the reviewers.
When reviewing a TC39 proposal, read the specification text, README and other documentation carefully. Some questions which may be useful to consider in a review:
- Does the proposal address its stated motivation?
- Is this language feature intuitive and learnable?
- Does the proposal fit in well when combined with other JavaScript language features (both current and proposed, a.k.a. "cross-cutting concerns")? Will the interactions between features be surprising or strange?
- Does the proposal scope make sense, or would this make more sense as a larger or smaller proposal?
- Does the specification text completely cover every aspect of the proposal, or are some things unstated?
- Is the specification text logical and consistent, matching the rest of the JavaScript specification?
- Do all of the details and edge cases seem reasonably motivated?
To give your feedback to the champion group, file issues in GitHub, or make pull requests with proposed changes.
Reviews are expected to be performed at least two weeks in advance of the TC39 meeting.