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
710
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
490
Vite+ Unified Toolchain for the Web
naokihaba
0
250
Swiftのレキシカルスコープ管理
kntkymt
0
220
net-httpのHTTP/2対応について
naruse
0
470
コンテキストの使い捨てをやめる — ビジネスルール駆動開発と miko —
ioki
0
190
過去最大のMCPアップデート! 2026-07-28 RC版の謎に迫る
licux
6
240
TAKTでAI駆動開発の品質を設計する
j5ik2o
6
1.2k
New "Type" system on PicoRuby
pocke
1
820
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
3.6k
TSKaigi Night Talks 2026_TypeScriptでサプライチェーンの整合性を型に閉じ込める
geekplus_tech
0
330
A2UI という光を覗いてみる
satohjohn
1
130
Claspは野良GASの夢をみるか
takter00
0
180
Featured
See All Featured
Navigating the moral maze — ethical principles for Al-driven product design
skipperchong
2
390
How to build a perfect <img>
jonoalderson
1
5.6k
AI Search: Where Are We & What Can We Do About It?
aleyda
0
7.6k
Getting science done with accelerated Python computing platforms
jacobtomlinson
2
220
New Earth Scene 8
popppiees
3
2.3k
The Cost Of JavaScript in 2023
addyosmani
55
10k
Design in an AI World
tapps
1
240
Test your architecture with Archunit
thirion
1
2.3k
Building AI with AI
inesmontani
PRO
1
1.1k
JavaScript: Past, Present, and Future - NDC Porto 2020
reverentgeek
52
6k
Rails Girls Zürich Keynote
gr2m
96
14k
GraphQLとの向き合い方2022年版
quramy
50
15k
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.