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
Daniel Cousineau
August 14, 2019
Programming
680
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
380
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
720
Other Decks in Programming
See All in Programming
軽量Java基盤の設計 DIコンテナに頼らない、長期保守と1秒起動の実現 JJUG CCC 2026 Spring
macha64
0
600
ADKを使って簡単にAIエージェントを作ってみよう
k1mu21
0
280
技術的負債解消で開発者の未来を開く- AIの力でコード刷新
kmd2kmd
0
120
Vite+ Unified Toolchain for the Web
naokihaba
0
360
Mujeres en SEO Summit 2026 - Greatest Disaster Hits en Web Performance
guaca
0
210
TypeScript+Orvalで実現する型安全かつ堅牢でスケーラブルなマルチチャネル通知基盤 / TSKaigi Night talks ~after conference~
d0riven
0
360
鹿野さんに聞く!『TypeScriptコードレシピ集』で磨く実践力
tonkotsuboy_com
4
860
AI駆動開発を妨げる技術的負債の解消アプローチ / ai-refactoring-approach
minodriven
15
7.3k
SREは、MCPとSRE Agentをこう使え!
kazumax55
0
120
Spring Security 実践 ─ GraphQL APIで実務に役立つ 認証・認可 を学ぶ
wagyu
0
260
「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
230
なぜ型を書くのか? TSKaigi2026で改めて考える #tskaigi_smarthr
kajitack
0
170
Featured
See All Featured
AI: The stuff that nobody shows you
jnunemaker
PRO
8
740
Rebuilding a faster, lazier Slack
samanthasiow
85
9.5k
The Power of CSS Pseudo Elements
geoffreycrofte
82
6.3k
The Invisible Side of Design
smashingmag
301
52k
Why Our Code Smells
bkeepers
PRO
340
58k
Easily Structure & Communicate Ideas using Wireframe
afnizarnur
194
17k
Joys of Absence: A Defence of Solitary Play
codingconduct
1
400
Conquering PDFs: document understanding beyond plain text
inesmontani
PRO
4
2.8k
The browser strikes back
jonoalderson
0
1.3k
How To Stay Up To Date on Web Technology
chriscoyier
790
250k
Heart Work Chapter 1 - Part 1
lfama
PRO
8
36k
How to Align SEO within the Product Triangle To Get Buy-In & Support - #RIMC
aleyda
2
1.6k
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.