- Host: Remote
- Dates and times:
- 10:00 to 15:00 PDT (America/Los_Angeles) on 28 July 2025
- 10:00 to 15:00 PDT (America/Los_Angeles) on 29 July 2025
- 10:00 to 15:00 PDT (America/Los_Angeles) on 30 July 2025
- 10:00 to 15:00 PDT (America/Los_Angeles) on 31 July 2025
- Location: Remote
- Attendee information:
- Total duration of scheduled discussions:
gantt
1 month before the meeting: milestone, 2025-06-28 10:00-0700, 1m
Proposal advancement deadline: milestone, 2025-07-18 10:00-0700, 1m
Schedule constraint deadline: milestone, 2025-07-25 10:00-0700, 1m
Day 1 : day1, 2025-07-28 10:00-0700, 7h
Day 2 : day2, 2025-07-29 10:00-0700, 7h
Day 3 : day3, 2025-07-30 10:00-0700, 7h
Day 4 : day4, 2025-07-31 10:00-0700, 7h
todayMarker stroke-width:5px,stroke:#0f0,opacity:0.5
For meeting times in your timezone, visit Temporal docs and run the code below in the devtools console.
Temporal.ZonedDateTime.from('2025-07-28T10:00[America/Los_Angeles]')
.withTimeZone(Temporal.Now.timeZoneId()) // your time zone
.toLocaleString();Background:
- Allen Wirfs-Brock's paper on standards committee participation for new attendees
- TC39's documentation on How to participate in meetings
Deadline for advancement eligibility: July 18th 10:00 PDT
- Note: this time is selected to be precisely 10 days prior to the start of the meeting
- Proposals not looking to advance may be added at any time; if after the deadline, please always use a pull request so that members are notified of changes. Note: an unmerged PR counts as “added” for the purposes of this requirement.
- Proposals seeking feedback at stage 0 must be added (and noted as such) prior to the deadline, or else delegates may object to advancement solely on the basis of missing the deadline.
- Such proposals should include supporting materials when possible.
- Proposals looking to advance to stage 1 must be added (and noted as such) prior to the deadline, or else delegates may object to advancement solely on the basis of missing the deadline.
- Such proposals must link to a proposal repository and they should link to supporting materials when possible.
- Proposals looking to advance to stages 2, 2.7, 3, or 4, as well as other normative changes to the standard or proposals in stage 3 or later looking to achieve consensus, must be added (and noted as such) along with links to the supporting materials prior to the deadline, or else delegates may withhold consensus for advancement solely on the basis of missing the deadline.
- If the supporting materials change substantially after the deadline, delegates may withhold consensus for advancement, based on the committee’s judgment.
- For urgent normative changes, the committee is expected to be more forgiving of a missed deadline, since there is generally less material to review than in a stage advancement.
- Proposals looking to advance to stage 4 must link to a pull request into the spec, since the process requires one.
- Proposal-based agenda items should be sorted primarily by stage (descending), secondarily by timebox (ascending), and finally by insertion date.
Supporting materials includes slides, a link to the proposal repository, a link to spec text, etc.; essentially, anything you are planning to present to the committee, or that would be useful for delegates to review.
When applicable, use these emoji as a prefix to the agenda item topic.
| Emoji | Meaning |
|---|---|
| ❄️ | hard schedule constraints apply to this agenda item (e.g. presenter) |
| 🔒 | schedule constraints apply to this agenda item |
| ⌛️ | late addition for stage advancement and/or schedule prioritization |
| 🔁 | continuation of a previous agenda item |
-
Opening, welcome and roll call (Chair)
- Opening of the meeting
- TC39 follows its Code of Conduct
- Introduction of attendees
- Host facilities, local logistics
- Quick recap of meeting IPR policy
- Overview of communication tools
- Reminder to review Github Delegate teams (Jordan Harband)
- TC39 stenography support and legal disclaimer
-
Find volunteers for note taking
-
Adoption of the agenda
-
Approval of the minutes from last meeting
-
Next meeting host and logistics
-
Secretary's Report (15m, Samina Husain) (slides)
-
Project Editors’ Reports
-
Task Group Reports
- TG3: Security (5m)
- TG4: Source Maps (5m)
- TG5: Experiments in Programming Language Standardization (5m)
-
Updates from the CoC Committee (5m)
-
Web compatibility issues / Needs Consensus PRs
timebox topic presenter 10m Missing name property for %IntlSegmentsPrototype%[%Symbol.iterator%](tc39/ecma402#1015, slides)Ujjwal Sharma 20m Spec/implementations divergence on module evaluation promises settlement order (tc39/ecma262/#3589, slides) Nicolò Ribaudo 20m F.p.toString incompat for builtin accessors (tc39/ecma262#3652) Keith Miller 20m TypedArray copyWithininconsistently responds to midstream shrinking (tc39/ecma262#3619)Richard Gibson -
Overflow from previous meeting
timebox topic presenter -
Short (≤30m) Timeboxed Discussions
timebox topic presenter 30m How to make thenables safer? (in-progress-slides) Matthew Gaudet (Mozilla) 30m Freezing the Array Iterator (slides) Kevin Gibbons 30m Proposed code of conduct addition: "write your own comments" (issue / slides) Kevin Gibbons 30m Preparing Summary and Conclusions (slides) Samina Husain & Aki Rose Braun -
Proposals
stage timebox topic presenter 3 5m Math.sumPrecise for Stage 4 (spec PR) Kevin Gibbons 3 5m Uint8Array base64+hex for Stage 4 (spec PR) Kevin Gibbons 3 20m Temporal normative PR (slides) Nicolò Ribaudo 2.7 15m Iterator Sequencing for Stage 3 (slides) Michael Ficarra 2.7 15m Upsert for Stage 3 (slides) Daniel Minor 2.7 30m Immutable ArrayBuffer for stage 3 (slides) Richard Gibson, Peter Hoddie 2.7 30m Non-extensible Applies to Private status update (slides.key, slides.pdf) Mark Miller 2 5m AsyncContext web integration update (slides) Andreu Botella 2 30m Iterator Chunking for Stage 2.7 (slides) Michael Ficarra 2 45m Intl Era and Month Code for Stage 2.7 (slides) Ujjwal Sharma 1 30m Error.captureStackTrace for Stage 2 (slides) Daniel Minor 1 30m Keep trailing zeros in Intl.NumberFormat and Intl.PluralRules for Stage 2 or 2.7 (slides) Eemeli Aro 1 30m Object.propertyCount for Stage 2 (slides TBD) Ruben Bridgewater 1 60m MeasureAmount for Stage 2 (slides)Eemeli Aro/Jesse Alama 0 30m Import Buffer for Stage 1, or ⌛ 2 (slides) Steven Salat 0 30m Array.isSparse for Stage 1 (slides TBD) Ruben Bridgewater 0 30m Array.getNonIndexStringProperties for Stage 1 (slides TBD) Ruben Bridgewater 0 30m Object.getOwnPropertySymbols options for Stage 1 (slides TBD) Ruben Bridgewater 0 60m Module Import Hook and new Global for Stage 1 (slides) Zbyszek Tenerowicz, Kris Kowal -
Longer or open-ended discussions
timebox topic presenter -
Overflow from timeboxed agenda items (in insertion order)
topic presenter Measure/Amount continuation Jesse Alama -
Incubation call chartering (15m on the last day)
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Other business
- Thank host
-
Adjournment
Schedule constraints should be supplied here as soon as possible, and at least three days before the meeting begins so that the Chairs can take them into account when preparing the schedule.
- Eemeli will be available on Day 1 from 11:30 onwards, and will not be available on Day 4. He would prefer to present on keep-trailing-zeros before the Measure/Amount presentation.
- Ruben will be able to attend one day only. It is not important which one. He would prefer to present all four proposals in one go, especially, since they are all somewhat related to each other.
- KG would like the base64 item scheduled after the Temporal normative PR item (not necessarily immediately after).
- The presentations for New Global and Import Hooks are in fact one presentation and should be scheduled together.
- Matthew Gaudet will have intermittent availability Monday due to life things, and so can't present 'How to make thenables safer?' that day.
- Mark Miller will not be ready to present Non-extensible Applies to Private on Monday. Any other day is fine.