October 31, 2014 Tristan Roussel 3 min read

I went to ParisJS meetup at Deezer headquarters last Wednesday with fellow colleagues Aurélie and Valentin. There were some awesome talks, so I'd like to give you some lightning advertising about them.

1st talk: Khalid Jebbari (GitHub, Twitter), meetup organizer, on GSS

Khalid spent most of his talk gunning down CSS on the basic things you want to accomplish simply but are forced to use dirty hacks (centering, here I come). A few people in the audience felt the need to defend it afterwards :) The problem he said is that when you're thinking of the layout, you're not thinking in a flow way but in a constraint way: I want to position my element relatively to another one.

Solution? GSS! Strongly inspired from Apple (still leading in design) Cocoa Autolayout, it uses constraints to compute the best layout possible based on them. DOM items are positioned absolutely and moved to their right place through CSS transformations. The project is not very mature, and the syntax sure feels heavy, but for once the paradigm can really bring back together a lot of front-end developers and layout.

His notes (in French): gss-paris-js

2nd talk: Jean-Loup Karst (Twitter) from breaz.io on statistics on technologies used by French start-ups

breaz.io is a company that bring together very passionate developers and French start-ups looking forward to recruiting them. Thanks to their business, they gather a lot of data on this ecosystem, especially on the leading technologies among them. We learned for example that PHP is still a huge backend technology for start-ups, but not as much as it is for the rest of the world (40% vs. 80%). Some global outsiders really shine in the French start-up world (Python, Node.js, Ruby). For front-end, the observations are equivalent, Angular.js surpasses jQuery, and we're very happy at Theodo to have developed a lot of applications lately with Angular.js.

Unfortunately, I felt the statistics lacked some significativity. I would have loved to have more confidence intervals (even just guessed) to draw more accurate conclusions from the graphs.

3rd talk: Gabriel Majoulet (Github, Twitter) from Brawker on Bitcoin applications in JavaScript

Gabriel explained (in a very simplified way for us newbies) how Bitcoin and blockchain transactions work. The aim of Bitcoin is to build a decentralized monetary system (partly) for security reasons, this goal is really undermined when we use huge platforms like Mt. Gox because they represent a single point of failure. We saw how it went for them. JavaScript has a central role to play in Bitcoin applications: you don't wont to store and use users clear private keys on your app server anymore. If you don't know anything then being hacked has no hard consequence. The solution is to store encrypted private keys on the server that the client can request and decrypt with his password and do Bitcoin operations directly from the browser without the server ever seeing a clear private key.

The subject is very passioning and security questions arise and really are interesting to discuss. For example, how do you know the JavaScript you're being served by the website is not a counterfeit? We can use PGP to ensure content is harmless, but not in an automatic way at the present moment.

His slides: parisjs-40-deezer-france

Lightning talk: Freddy Harris (GitHub, Twitter) on Hello.js

Freddy briefly presented Hello.js, a JavaScript library for client-side OAuth authenticating. It is already configured with some major websites (Facebook, Google, Twitter...) and you can add a new one very easily. It supports OAuth 2.0 implicit grant, OAuth 2.0 explicit grant and OAuth 1.0 and OAuth 1.0a.

His slides: hello-presentation

Conclusion

I will definitely keep going to ParisJS meetup and I enjoin all the other Paris front-end (or not) developers to come and share some good time with us!