Introducing RequireJS Into a Large Codebase. Delicately.Dan Lee & Chris Chen

2008 TechCrunch 50

Source: http://techcrunch.com/2008/09/10/yammer-takes-techcrunch50s-top-prize/

get_it_done.js- nested erb partials- deferred JS- variable interpolation- global jQuery

@polotek @techwraith @mde

@foobarfighter @peterbraden @mattkauffman

They made us better.

Modular components

build.jsonor manifest.ymlor scripts.json…

Build and Deployment

build.json Asset Pipeline

application.js CDN

Bob wants more.

Popout Chat

“Programming out of Anger”

The Chat Bundle ChatBundle

ChatManager

ContactList ChatSession

ChatSessionNotifications ChatMessageList

ChatMessageListItem

Avatar

ChatPublisher

ChatAggregator ChatBridge

AMD’ing ChatManager

But chat also loads on yammer.com…

define() doesn’t exist

We needed a version of define() that ignored dependencies.

So we shimmed it.

Wait, don’t get up…Think about the possibilities.

Feature flags that aren’t used for features…

The resultsBefore:Compressed: 531kbUncompressed: 2048kb

After:Compressed: 216kbUncompressed: 715kbA 60% reduction!

build.json Asset Pipeline

Way too much JS CDN

ChatBundle r.js optimizer popout_chat.js CDN

The dream is real.Yammer is saved!

But, we didn’t really save Yammer.- AMD’ed a small percentage of files- Dev environment setup- Two worlds- Global namespaces

How we moved forward.And there is still more to do.

Reflection

- Big- Deployed often- Many, globally distributed contributors

Codebase challenges

1. Isolation

2. Iteration

3. Minimize Disruption

‘Code in Transition’ is OK

Transition or Stagnation:Choose One.

© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.