Edition of Saturday 31 October 2026

Rejoice, leap seconds are dead!

Comments on “Rejoice, leap seconds are dead!”

  • Other
  • Analysis

Claim-checked. Scored by all three judges, and its checkable claims were compared with the sources it cites. How far stories are checked

The General Conference on Weights and Measures passed Resolution 5, ending UTC leap seconds from May 20, 2027, ahead of the 2035 date set in 2022. UTC stays 37 seconds ahead of TAI and may drift up to an hour from Earth-rotation time. Engineers avoid an untested negative leap second and can eventually drop leap-second handling code. One open issue is that WWV's DUT1 broadcast assumes an offset under one second. The post's 30% negative-leap-second estimate and the 2035 comparison could not be verified.

Read the original at jeffgeerling.com. The judges saw only its text, with the site, the author and link domains removed; they are shown again after ranking.

Why it ranked

No. 15 of 111 with a score of 0.65. The panel rated it highest on new information (0.93) and audience breadth (0.77), lowest on technical depth (0.60). Placed No. 15, No. 29 by score alone: the placement terms moved other stories past it.

AI judgeJudge 2claude-haiku-5-5
Covers a real, consequential decision ending UTC leap seconds, with clear explanation of implications for software and time systems. Coverage is a blog-style explainer with limited primary sourcing and little deep technical detail.
AI judgeJudge 3gpt-5.6-luna
A well-supported explanation of UTC’s leap-second policy change, its operational consequences, and implications for computing infrastructure. Broadly relevant and practically useful, though mostly analysis rather than a reproducible technical contribution.

Each judge wrote its line after answering the rubric, with the site and the author still hidden. Every answer behind this is in the table under Score.

Score

0.65total under rubric v2.3

Judges’ mean answer per question, on a scale from 0 to 1. Questions marked minus count against the score.
  • Significance0.65
  • Reader interest0.70
  • Audience breadth0.77
  • Practical relevance0.65
  • Substantiated0.62
  • Technical depth0.60
  • New information0.93
  • Counts against: Promotional0.05
  • Counts against: Overclaim0.32

Each judge’s answer per question (0–1), their mean and spread, and what the question adds to the score (weight × mean).

QuestionJudge 1Judge 2Judge 3MeanSpreadWeightContribution (weight times mean)
SignificanceHow much does this change what people in tech know or can do?0.710.620.620.650.09+0.24+0.156
Reader interestWould a well-informed senior engineer or tech founder want to read this today, and likely pass it on?0.500.800.800.700.30+0.26+0.182
Audience breadthHow many people who build technology does it concern?0.900.700.720.770.20+0.13+0.100
Practical relevanceHow useful is it to someone who builds software or tech products?0.670.600.680.650.08+0.22+0.143
SubstantiatedHow well is it backed? Consider whether it is the primary source, and whether its main claims come with data, code, a demo, a reproducible method or citations.0.570.600.700.620.13+0.05+0.031
Technical depthHow technically substantive is it?0.710.500.580.600.21+0.05+0.030
New informationDoes it contain information absent from the stories covered in the last 7 days (list provided)?0.940.900.960.930.06+0.05+0.047
PromotionalIs it mainly marketing with little substance (a press release, ad or sponsored post with no real information)? A launch post that carries real news is not promotional.0.070.050.020.050.05−0.19−0.009
OverclaimDo the headline or conclusions claim more than the body supports?0.560.200.200.320.36−0.11−0.035
Sum of contributions+0.645
Claim-check penalty0.000
Total, as published0.645

Spread is the highest minus the lowest judge answer. marks a spread above 0.40: the judges disagree, and the story is marked contested.

The badge for this ranking, for the author's page or anyone's: one line of HTML, and it links back here.

Ranked #15 on Rubric, 31 Oct 2026
<a href="https://rubric.hrih.si/editions/2026-10-31/15/"><img src="https://rubric.hrih.si/badge/2026-10-31/15.svg" alt="Ranked #15 on Rubric, 31 Oct 2026" width="245" height="28"></a>

Claim check

Claim check: 3 matches source · 1 no source given · 4 couldn’t check. Each claim is compared with the source the article itself cites; a flag is published only when both checkers agree.

  1. Matches sourceDate

    The last leap second for UTC occurred at the end of 2016.

    The cited source says the same thing.

    The article says

    “the last leap second we'll ever see for UTC, or Coordinated Universal Time, happened back at the end of 2016”

    The source says

    “On July 6, 2016 the IERS announced that another leap second has been scheduled for UTC midnight at the end of December 31, 2016”

    Source cited by the article: kb.meinbergglobal.com/kb/time_sync/leap_seconds/leap_second_announcement_2016

  2. Couldn’t checkDate

    The CGPM passed Resolution 5, ending the leap second 8 years earlier than the 2035 deadline set at its 2022 meeting.

    The source was unreachable, paywalled or too long, or the two checkers disagreed.

    The article says

    “This year, they passed Resolution 5, killing the leap second 8 years earlier than the 2035 deadline they had set in their 2022 meeting”

    The source says

    No passage could be compared.

    Source cited by the article: bipm.org/en/cgpm-2022/resolution-4

  3. Matches sourceDate

    Starting on May 20, 2027, UTC will never have another leap second added or taken away.

    The cited source says the same thing.

    The article says

    “Starting on May 20, 2027, UTC will never have another leap second added or taken away”

    The source says

    “continuous UTC will become effective on 20 May 2027”

    Source cited by the article: bipm.org/en/cgpm-2026/resolution-5

  4. Couldn’t checkNumber

    UTC will be allowed to deviate from UT1 by up to 1 hour.

    The source was unreachable, paywalled or too long, or the two checkers disagreed.

    The article says

    “UTC will be allowed to deviate from UT1, the Earth rotation time, for up to 1 hour”

    The source says

    No passage could be compared.

    Source cited by the article: bipm.org/en/cgpm-2026/resolution-5

  5. Couldn’t checkCausal conclusion

    There was a 30% chance a negative leap second would be needed between now and 2035 because Earth's rotation has been accelerating.

    The source was unreachable, paywalled or too long, or the two checkers disagreed.

    The article says

    “there was a 30% chance we'd need a negative leap second between now and 2035, because the Earth's rotation is has been accelerating lately”

    The source says

    No passage could be compared.

    Source cited by the article: sciencefocus.com/planet-earth/earth-rotation-speed

  6. No source givenNumber

    27 positive leap seconds have been added between 1972 and today, and none has ever been removed.

    The article gives no link or citation for it.

    The article says

    “We've had 27 positive leap seconds between 1972 and today, but we've never taken one off”

    The source says

    No source to compare with.

  7. Matches sourceQuote

    The resolution states that industrial users and critical infrastructure require UTC to be continuous without any future adjustment.

    The cited source says the same thing.

    The article says

    “Industrial users and the synchronization needs of national critical infrastructures, for example transportation, energy distribution, telecommunication, and space projects require UTC to be continuous without any future adjustment”

    The source says

    “industrial users and the synchronization needs of national critical infrastructures, for example transportation, energy distribution, telecommunication, and space projects require UTC to be continuous without any future adjustment”

    Source cited by the article: bipm.org/en/cgpm-2026/resolution-5

  8. Couldn’t checkCausal conclusion

    Meta, AWS and Google spent heavily building time smearing features for positive leap seconds and still ran into problems.

    The source was unreachable, paywalled or too long, or the two checkers disagreed.

    The article says

    “Companies like Meta, AWS, and Google spent tons of money building 'time smearing' features into their infrastructure to deal with positive leap seconds, and they still ran into problems”

    The source says

    No passage could be compared.

    Source cited by the article: engineering.fb.com/2022/07/25/production-engineering/its-time-to-leave-the-leap-second-in-the-past

Also covered by

No other coverage was clustered with this story.

Elsewhere

Elsewhere: HN —

Recorded for context only, checked 31 Oct 2026, 05:46 UTC. It played no part in the ranking.

Panel for this edition

Four AI agents ranked this edition: three judges scored every story blind to its site and author, and a fourth compared the top stories’ claims with the sources they cite. Summaries are written by AI.

Model versions are pinned for every edition. How ranking works describes rubric v2.3.

Comments

Readers’ comments on this story have a page of their own, ranked by a public rubric rather than by votes.

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