Craig Condongithub.com/crcn

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Hi, I’m Craig

•Engineer for 12 years

•Focus on application architecture

•Built browsertap.com, photomotr.com, cloveapp.com

•Full stack engineer at ClassDojo

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ClassDojo

• startup

•One of the fastest growing ed-tech company in history

•Backed by Jeff Clavier, Ron Conway and Paul Graham

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Approaching ubiquity across the US

(teachers only)

(Slide Redacted)

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Why?

•Self directed— able to pick whatever we want to work on

•High impact & high growth

•Flexible work schedule

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History of JavaScript at ClassDojo

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StackRequireJSfront-end:

view partials generated from backend

back-end:

testing:

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Front-end Problems

•Quickly built

•Little structure, not maintainable

•Hard to add new features

•36,000 LOC

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Why not an existing MV* Framework?

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Framework Requirements

•Not a lot of features

•Compatible with existing libraries

•Strangles old code out

•Testability

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Framework Fears

•Backbone compatibility

•IE compatibility

•Modularity

•Strangleability

•Unforeseen consequences

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•Built to phase out old code, and itself

•Node.js philosophy

•Module-based

•Organization

Mojo.js

Inspired by

… and others!

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Sketch

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Scaffold & Implement

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v0.1

•Designed after Backbone.js, and jQuery

•Interchangeable parts

•Bindable.js - inspired by ember bindings

•Usable anywhere in the application

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Dojo v1

Dojo v2(Mojo)

Phase in, Phase out

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Dojo v1

Dojo v2(Mojo)

Phase in, Phase out

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Old ArchitectureDojo v2(Mojo)

Phase in, Phase out

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Old Architecture

Dojo v2(Mojo)

Phase in, Phase out

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Challenges

•Evolution, refactoring

•innerHTML browser inconsistencies

•Stack overflows

•Feedback

•Wanted to dev faster

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v0.2

•Paperclip module

•Declarative two-way data-binding inspired by

•DOM shims

•100% JavaScript, including templates

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http://jsperf.com/dom-vs-innerhtml

innerHTML vs appendChild

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Framework Comparison

1. build HTML string 2. call innerHTML 3. traverse and & bind

1. call innerHTML 2. traverse and & bind

1. build DOM & bind

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Current Status• Template Engine - declarative two-way data-

binding, similar to Handlebars

• Components - Ember-style components in templates - <div> {{#chart}} </div>

• Models - bindable objects / collections - communicates with API

• Router - HTTP router

• Mediator - Abstracts communication between parts of the application

• Testing - Testing Framework

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Team Productivity

•Build on top of existing code base

•Sketches > Scaffolding > Implementation

• Improved collaboration

•Reduced code bloat

•Rapid iterations

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student.classdojo.com

• 3 weeks to design & develop

• 2.5K LOC

• Developed backend & front-end independently

• Easy to test

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Demo

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Resources

•Mojo.js - core framework

•Mojo Starter - starter kit for building applications

•ClassDojo - Company

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•Node.js support (derby / meteor style)

•Mojo Inspector

•More plugins

•Plugin catalogue

What’s next?

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Craig Condongithub.com/crcn

github.com/classdojo/mojo.js

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Thanks!Craig Condon

github.com/crcn

github.com/classdojo/mojo.js

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