Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Time is a Social Construct
Search
Sponsored
·
Your Podcast. Everywhere. Effortlessly.
Share. Educate. Inspire. Entertain. You do you. We'll handle the rest.
→
Daniel Cousineau
August 14, 2019
Programming
690
1
Share
Embed
Copy iframe code
Copy JS code
Copy link
Start on current slide
Time is a Social Construct
Given at BrooklynJS, ManhattanJS, and JSConf 2019
https://www.youtube.com/watch?v=EUzPpXhFmG8
Daniel Cousineau
August 14, 2019
More Decks by Daniel Cousineau
See All by Daniel Cousineau
React @ Scale
dcousineau
0
230
Frontend Performance & You
dcousineau
0
390
Feature Flags & You
dcousineau
2
120
React+Redux @ Scale
dcousineau
1
360
Reframing The Problem - DCJS July 2016
dcousineau
0
150
YAFT
dcousineau
2
160
Queues and the beanstalkd
dcousineau
1
720
How Not Writing PHP Makes You Better At PHP
dcousineau
0
410
JavaScript for PHP Developers
dcousineau
4
730
Other Decks in Programming
See All in Programming
Dataformのリポジトリを立ち上げるときにまずやること / dataform-day0-2026
snhryt
0
210
AIを活用したE2Eテスト実装効率化のあゆみ / ebisu-mobile-14-kotetu
kotetuco
0
160
決定論的オーケストレーションの設計と実装 / Design and Implementation of Deterministic Orchestration
nrslib
4
1.6k
LLM本来の能力を解き放つサンドボックス技術とAI民主化への適用
yukukotani
3
4.8k
「なぜそう決めたのか」を残し続ける仕組み ― Notion AI カスタムエージェント × Slack連携による設計判断の自動記録 - NIKKEI Tech Talk #47
niftycorp
PRO
0
250
Agentic UI
manfredsteyer
PRO
0
220
Language Server 使ってる? 〜VSCode と Zed の場合〜 / Are you using a Language Server? ~For VS Code and Zed~
handlename
0
820
分散システム、なんですぐ死んでしまうん?耐障害性を高めたいあなたのためのレジリエンスパターン入門
mshibuya
3
980
ローカルLLMを使ってB2Bサービスを作っていての学び
yaotti
0
230
なぜ型を書くのか? TSKaigi2026で改めて考える #tskaigi_smarthr
kajitack
0
190
才能?センス?知らん、 続けたもん勝ちだ。-- 結婚・出産・癌を越えてなお、私がプロダクトを創り続ける理由
16bitidol
2
650
Oxcを導入して開発体験が向上した話
yug1224
4
370
Featured
See All Featured
How Fast Is Fast Enough? [PerfNow 2025]
tammyeverts
3
640
Joys of Absence: A Defence of Solitary Play
codingconduct
1
410
What’s in a name? Adding method to the madness
productmarketing
PRO
24
4.1k
Deep Space Network (abreviated)
tonyrice
0
220
The agentic SEO stack - context over prompts
schlessera
0
840
Building a Scalable Design System with Sketch
lauravandoore
463
34k
Build The Right Thing And Hit Your Dates
maggiecrowley
39
3.2k
Building Flexible Design Systems
yeseniaperezcruz
330
40k
Put a Button on it: Removing Barriers to Going Fast.
kastner
60
4.3k
Designing Dashboards & Data Visualisations in Web Apps
destraynor
231
55k
The Pragmatic Product Professional
lauravandoore
37
7.3k
Google's AI Overviews - The New Search
badams
0
1.1k
Transcript
@dcousineau TIME IS A SOCIAL CONSTRUCT
@dcousineau SOCIAL CONSTRUCTS ARE GARBAGE
@dcousineau TIME IS GARBAGE
@dcousineau @dcousineau IS GARBAGE he/him
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau 12pm Aug 15th, 2019
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau 12pm Aug 15th, 2019 UTC-0400
@dcousineau
@dcousineau 2019-08-15T12:00:00-0400
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau 2019-08-15T16:00:00Z
@dcousineau @dcousineau
@dcousineau @dcousineau
@dcousineau Daylight Savings Time @dcousineau
@dcousineau Sun, Mar 10 @ 2am to Sun, Nov 3
@ 2am
@dcousineau 2019-08-15T16:00:00Z 2019-11-04T16:00:00Z 12pm in New York 11am in New
York
@dcousineau
@dcousineau
@dcousineau Arizona is in the Mountain Timezone and does not
observe daylight savings time except in the Navajo Indian Nation.
@dcousineau
@dcousineau Standard DST
@dcousineau 2019-03-10T02:01:00-07:00 “Fun” Fact Quiz
@dcousineau 2019-03-10T02:01:00-07:00 “Fun” Fact Quiz
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau @dcousineau
@dcousineau
@dcousineau
@dcousineau America/New_York EST America/Chicago CST America/Denver MST America/Phoenix MST …
@dcousineau America/Indiana/Indianapolis America/Indiana/Knox America/Indiana/Marengo America/Indiana/Petersburg America/Indiana/Tell_City America/Indiana/Vevay America/Indiana/Vincennes America/Indiana/Winamac
@dcousineau Maybe Wikipedia can help…
@dcousineau
@dcousineau
@dcousineau 1918–1961
@dcousineau 1961–1967
@dcousineau 1967–1977
@dcousineau 1977–1991
@dcousineau 1991–2006
@dcousineau 2006–March 2007
@dcousineau March 2007–November 2007
@dcousineau November 2007–Today
@dcousineau America/New_York: Dearborn & Ohio America/Chicago: Jasper, Lake, LaPorte, Newton,
Porter, Gibson, Posey, Spencer, Vanderburgh, & Warrick America/Kentucky/Louisville: Clark, Floyd, & Harrison Counties in Indiana NOT on America/Indiana/*
@dcousineau 2019-08-15T12:00:00-0400 America/New_York
@dcousineau
@dcousineau So… did we learn anything?
@dcousineau Treat time as if it is irreducibly complex.
@dcousineau Time is a question of where almost as much
as it’s when.
@dcousineau Treat UTC like it’s merely a synchronization and conversion
aid.
@dcousineau Always preserve presented offsets / timezones. Only clone &
convert into UTC if storage requires.
@dcousineau Use ISO-8601 in transit & let the browser handle
the rest. Treat it like a11y, give the browser / user control.
@dcousineau Be explicit about context with your user. If this
is confusing for you, it’s worse for them.
@dcousineau USE A LIBRARY! Especially for simple arithmetic. date-fns, moment.js,
Luxon
@dcousineau When all else fails, just move to Florida. ☀
@dcousineau fin.