Why code in Node . js often get rejected by SoundCloud Phil Calado - - - PowerPoint PPT Presentation

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Dec 15, 2022 237 likes •867 views

Why code in Node . js often get rejected by SoundCloud Phil Calado - SoundCloud @pcalcado http :// philcalcado . com Tuesday, October 1, 13 2011: Phil zieht nach Berlin Tuesday, October 1, 13 Tuesday, October 1, 13 > 11 hours of audio

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Why code in Node.js

ften get rejected by

SoundCloud

Phil Calçado - SoundCloud @pcalcado http://philcalcado.com

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2011: Phil zieht nach Berlin

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~ 200 million users / month > 11 hours of audio uploaded every minute

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http://bit.ly/15DToNK

hiring @ SoundCloud

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Phone Code Review Interviews Ofger

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Phone Code Review Interviews Ofger

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challenge until late 2012

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you can choose any language.

10 20 30 40 Ruby Java JavaScript (Node.js) C Clojure Scala

% of submissions ~2011-2012

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you can choose any language.

10 20 30 40 Ruby Java JavaScript (Node.js) C Clojure Scala

rejected before interview invited for inverview

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new challenge

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you can choose any language.

7.5 15 22.5 30 Ruby Java JavaScript (Node.js) Go Clojure Scala

% of submissions on the past ~1 year

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you can choose any language.

7.5 15 22.5 30 Ruby Java JavaScript (Node.js) Go Clojure Scala

% of submissions on the past ~1 year

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you can choose any language.

7.5 15 22.5 30 Ruby Java JavaScript (Node.js) Go Clojure Scala

rejected before interview invited for inverview

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you can choose any language.

7.5 15 22.5 30 Ruby Java JavaScript (Node.js) Go Clojure Scala

rejected before interview invited for inverview

WTF?

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http://bit.ly/J1aLNn

don’t get me wrong we are all hipsters

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

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http://bit.ly/JiECRp

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

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http://bit.ly/JiFSnq

so how do we structure our app?

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what to use?

(decent) procedures?

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what to use?

bjects?

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what to use?

...functions?

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http://bit.ly/JFbZt8

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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 [...]”

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http://bit.ly/JiEQYM

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http://bit.ly/JiF7ef

going old school

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e.g. passing functions around

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we see a lot of this

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1st, we extract what is common

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then we refactor our functions

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and we send them as arguments

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e.g. closures not only for objects

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we see a lot of this

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we can keep writeComment as it is

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and we add a function with two closures

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and we add a function with two closures

immutable

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and we add a function with two closures

immutable mutable

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

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e.g. functions all the way down

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we see a lot of this

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first we extract common protocol

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then we clean up our functions

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then we use them.

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then we use them.

redundant?

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http://bit.ly/JiETnd

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ur “framework”:

1 - Extract protocol in “combinators” 2 - Keep mutable state in closures

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no scary monads required

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there is plenty to learn from

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in the javascript community too

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phil calçado http://philcalcado.com @pcalcado

www.soundcloud.com

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How to Design Programs - http://bit.ly/K0BfrL Structure 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/

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