why code in node.js often get rejected by soundcloud

Why code in Node.js often get rejected by

SoundCloud

Phil Calçado - SoundCloud@pcalcado

http://philcalcado.comTuesday, October 1, 13

2011: Phil zieht nach Berlin

Tuesday, October 1, 13

~ 200 million users / month

> 11 hours of audio uploaded every minute

http://bit.ly/15DToNK

hiring @ SoundCloud

Code Review

Interviews

Code Review

Interviews

challenge until late 2012

you can choose any language.

Ruby Java JavaScript (Node.js) C Clojure Scala

% of submissions ~2011-2012

Ruby Java JavaScript (Node.js) C Clojure Scala

rejected before interview invited for inverview

new challenge

Ruby Java JavaScript (Node.js) Go Clojure Scala

% of submissions on the past ~1 year

http://bit.ly/J1aLNn

don’t get me wrong

we are all hipsters

Not OO, not Functional...Just (bad) Procedural code.

http://bit.ly/JiECRpTuesday, October 1, 13

we don’t need this complicated stuff.this is not java, you know.

http://bit.ly/JiFSnq

so how do we structure our app?

what to use?

(decent)procedures?

what to use?

objects?

what to use?

...functions?

http://bit.ly/JFbZt8Tuesday, October 1, 13

http://bit.ly/JFbZt8

“SICP and some of the Sussman & Steele "Lambda the ..." papers made a big impression on me years before, although I did not understand their full meaning then.Remember, I was recruited to "do Scheme" [...] My interest in languages such as Self informed a subversive agenda [...]. Likewise with first-class functions, which were inspired by Scheme [...]”

http://bit.ly/JiEQYMTuesday, October 1, 13

http://bit.ly/JiF7ef

going old school

e.g. passing functions around

we see a lot of this

1st, we extract what is common

then we refactor our functions

and we send them as arguments

e.g. closures not only for objects

we can keep writeComment as it is

and we add a function with two closures

immutable

immutablemutable

now we don’t need to pass in the kitchen sink

e.g. functions all the way down

first we extract common protocol

then we clean up our functions

then we use them.

then we use them. redundant?

http://bit.ly/JiETndTuesday, October 1, 13

our “framework”:1 - Extract protocol in

“combinators”2 - Keep mutable state in

closures

no scary monads required

there is plenty to learn fromTuesday, October 1, 13

in the javascript community tooTuesday, October 1, 13

phil calçado

http://philcalcado.com@pcalcado

www.soundcloud.com

How to Design Programs - http://bit.ly/K0BfrLStructure and Interpretation of Computer

Programs - http://bit.ly/K0BjYm

The Art of the Metaobject Protocol http://amzn.to/K0BqU1

Purely Functional Data Structures http://amzn.to/JFn4KG

Let Over Lambda - http://amzn.to/IMMkNO

An Introduction to Lambda Calculi for Computer Scientists - http://amzn.to/IX8d1B

All drawings are available as t-shirts from the awesome Diesel Sweeties - http://dieselsweeties.com/

why code in node.js often get rejected by soundcloud

clojure scala

clojure scala

interview

closures tuesday

inverview

functions

functions

tuesday

Technology

how to buy soundcloud likes to blow up fast on soundcloud?

soundcloud, web2expo 08

node.js workshop- node.js unit testing

soundcloud api learnings

node.js workshop- node.js basics

function composition: the top reason node.js submissions get...

buy soundcloud marketing - promote your soundcloud music

microservices @ soundcloud

soundcloud tutorial

soundcloud expert review

soundcloud dropbox

finagle @ soundcloud

buy soundcloud plays

youtube + soundcloud

node.js workshop- node.js databases

soundcloud إستعمال خدمة

soundcloud followers

data democratization at soundcloud - bruno sá (soundcloud)

tutorial soundcloud

"Добро пожаловать в soundcloud!"....