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
Failure Teaches Success
Search
Sponsored
·
SiteGround - Reliable hosting with speed, security, and support you can count on.
→
Hiromu Shioya
July 17, 2014
Technology
0
4.4k
Failure Teaches Success
2014-07-17 System Lightning Talks Bar Vol.2
"Failure Teaches Success" by kwappa
Hiromu Shioya
July 17, 2014
Tweet
Share
More Decks by Hiromu Shioya
See All by Hiromu Shioya
成長自己責任時代のあるきかた/How to navigate the era of personal responsibility for growth
kwappa
4
870
礼節とHRTと心理的安全性(2025年9月版)/Civility, HRT and Psychological Safety(Sep. 2025 edition)
kwappa
0
200
はじめての転職講座/The Guide of First Career Change
kwappa
6
5.5k
My Generation 年配者がこの先生きのこるには (Developers CAREER Boost 2024 Edition)/My Generation How elder engineers can survive
kwappa
5
2k
三大あいまい能力/Three ambiguous abilities
kwappa
1
370
My Generation 年配者がこの先生きのこるには/My Generation How elder engineers can survive
kwappa
3
6.6k
勝ちに不思議の勝ちあり、負けに不思議の負けあり/There is a mystery to win, but there is no mystery to lose
kwappa
0
380
伸び代だらけのチームに 伸びてもらうための施策100連発/100 measures to grow up a team with a lot of growth potential
kwappa
1
310
HIGH OUTPUT Infrastructure Engineering
kwappa
1
77
Other Decks in Technology
See All in Technology
All About Sansan – for New Global Engineers
sansan33
PRO
1
1.4k
20260305_【白金鉱業】分析者が地理情報を武器にするための軽量なアドホック分析環境
yucho147
1
190
Windows ネットワークを再確認する
murachiakira
PRO
0
290
ビズリーチにおける検索・推薦の取り組み / DEIM2026
visional_engineering_and_design
1
110
Kaggleで鍛えたスキルの実務での活かし方 競技とプロダクト開発のリアル
recruitengineers
PRO
1
180
Introduction to Sansan for Engineers / エンジニア向け会社紹介
sansan33
PRO
6
72k
AWS DevOps Agent vs SRE俺 / AWS DevOps Agent vs me, the SRE
sms_tech
2
250
DevOpsエージェントで実現する!! AWS Well-Architected(W-A) を実現するシステム設計 / 20260307 Masaki Okuda
shift_evolve
PRO
3
210
JAWS DAYS 2026 CDP道場 事前説明会 / JAWS DAYS 2026 CDP Dojo briefing document
naospon
0
200
チームメンバー迷わないIaC設計
hayama17
5
4k
開発組織の課題解決を加速するための権限委譲 -する側、される側としての向き合い方-
daitasu
5
280
大規模サービスにおける レガシーコードからReactへの移行
magicpod
1
150
Featured
See All Featured
Refactoring Trust on Your Teams (GOTO; Chicago 2020)
rmw
35
3.4k
The Impact of AI in SEO - AI Overviews June 2024 Edition
aleyda
5
760
Typedesign – Prime Four
hannesfritz
42
3k
The Pragmatic Product Professional
lauravandoore
37
7.2k
Automating Front-end Workflow
addyosmani
1370
200k
The Myth of the Modular Monolith - Day 2 Keynote - Rails World 2024
eileencodes
26
3.4k
Between Models and Reality
mayunak
2
230
ラッコキーワード サービス紹介資料
rakko
1
2.5M
Leadership Guide Workshop - DevTernity 2021
reverentgeek
1
230
HU Berlin: Industrial-Strength Natural Language Processing with spaCy and Prodigy
inesmontani
PRO
0
250
Build The Right Thing And Hit Your Dates
maggiecrowley
39
3.1k
Skip the Path - Find Your Career Trail
mkilby
1
72
Transcript
Failure Teaches Success 2014-07-17! System Lightning Talks Bar Vol.2! SHIOYA,
Hiromu (@kwappa)
Hello, World!
kwappa SHIOYA Hiromu
None
http://cookpad.com
http://info.cookpad.com
http://bit.ly/cookpadjobs
Failure Teaches Success
CASE 1 1998
FLAG SHOULD NEVER COMPARE TO 1
FOR EXAMPLE
!!! BUG !!! item[42] # => 0
!!! BUG !!! item[42] # => 1
!!! BUG !!! item[42] # => 2
!!! BUG !!! item[42] # => 3
!!! BUG !!! item[42] # => 4
!!! BUG !!! item[42] # => 5
DEAD END
BETTER ONE
CASE 2 2008
BOSS SHOULD NEVER DEPLOY
NEW BOSS CAME AND TOLD US
NEW BOSS CAME AND TOLD US I USED TO CODE,
BUT I TOOK AN ARROW IN THE KNEE...
OUR SYSTEM commit checkout rsync DEVELOPER SVN STAGING DEPLOY PRODUCTION
HERE COMES THE BOSS rsync STAGING DEPLOY PRODUCTION
HERE COMES THE BOSS login rsync STAGING DEPLOY PRODUCTION
HERE COMES THE BOSS login rsync STAGING DEPLOY PRODUCTION $vi
regist.php
HERE COMES THE BOSS login rsync STAGING DEPLOY PRODUCTION $vi
regist.php $rm regist.php
HERE COMES THE BOSS login rsync STAGING DEPLOY PRODUCTION $vi
regist.php $rm regist.php $svn hogehoge
HERE COMES THE BOSS login rsync STAGING DEPLOY PRODUCTION $vi
regist.php $rm regist.php $svn hogehoge $./deploy.sh
CASE 3 2014
ERRORS SHOULD NEVER PASS SILENTLY
http://www.flickr.com/photos/chrisdonia/3460805358/
http://www.flickr.com/photos/chrisdonia/3460805358/ ʊਓਓਓਓਓਓਓਓਓਓਓਓਓਓʊ ʼ 500 ʻ ʼ INTERNAL SERVER ERROR ʻ
ʉY^Y^Y^Y^Y^Y^Y^Y^Y^Y^Y^Y^Yʉ
OAuth2::Response#parsed # => nil
https://github.com/intridea/oauth2/commit/ 56f9758d961fc317a05b2f93fd039588967a84b1
None
None
None
None
WHY DID IT WORK? multi_xml oauth2 requires
WHY DID IT WORK? multi_xml httparty oauth2 requires depends
WHY DID IT WORK? aws-sdk-ruby multi_xml httparty oauth2 requires depends
depends
WHY DID IT BRAKE?
WHY DID IT BRAKE? Gemfile
WHY DID IT BRAKE? Gemfile.lock Gemfile
https://github.com/aws/aws-sdk-ruby/commit/ c25952ed50d568172de6eb1756525a35eeb2fa77
WHY DID IT BREAK? aws-sdk-ruby multi_xml httparty oauth2 requires depends
depends
WHY DID IT BREAK? aws-sdk-ruby multi_xml httparty oauth2 requires depends
WHY DID IT BREAK? aws-sdk-ruby multi_xml oauth2 requires
WHY DID IT BREAK? aws-sdk-ruby oauth2 requires
WHY DID IT BREAK? aws-sdk-ruby oauth2 requires ʊਓਓਓਓਓਓਓਓਓਓਓਓਓਓʊ ʼ 500
ʻ ʼ INTERNAL SERVER ERROR ʻ ʉY^Y^Y^Y^Y^Y^Y^Y^Y^Y^Y^Y^Yʉ
CONCLUSION
FLAG SHOULD NEVER COMPARE TO 1
FLAG SHOULD NEVER COMPARE TO 1 BOSS SHOULD NEVER DEPLOY
FLAG SHOULD NEVER COMPARE TO 1 BOSS SHOULD NEVER DEPLOY
ERRORS SHOULD NEVER PASS SILENTLY
Failure Teaches Success SHARE YOUR FAILURES!!! THANK YOU FOR LISTENING