December 13, 2011 § 7 Comments
One of the key components of
In a previous post, I introduced
OS.File, a Mozilla Platform library designed make the life of developers easier and to help them produce high-performance, high-responsiveness file management routines.
In this post, I would like to concentrate on one of the core items of
OS.File: the Schedule API. Note that the Schedule API is not limited to
OS.File and is designed to be useful for all sorts of other modules.
November 19, 2011 § 1 Comment
edit Nous sommes pleins jusqu’à Juin. Nous ne pouvons plus prendre de stagiaires sur Paris dont les stages commencent avant Juin.
Comme tous les ans, Mozilla propose des stages en informatique, orientés Développement, R&D ou Recherche. Selon le sujet, le stage peut vous emmener à Paris, aux États-Unis, au Canada, en Chine…
À propos de Mozilla
La Fondation Mozilla est une association à but non-lucratif, fondée pour encourager un Internet ouvert, innovant et participatif. Vous avez probablement entendu parler de Mozilla Firefox, le navigateur open-source qui a réintroduit sur le web les standards ouverts et la sécurité, ou de Mozilla Thunderbird, le client de messagerie multi-plateforme, open-source et extensible. Les activités de Mozilla ne s’arrêtent pas à ces deux produits et se prolongent à de nombreux projets pour le présent et l’avenir, tels que :
Boot-to-Gecko, système d’exploitation totalement ouvert et construit par la communauté, pour les téléphones portables, tablettes et autres machines communicantes ;
Rust, un nouveau langage de programmation conçu pour le développement d’applications système parallèles sûres ;
WebAPI, un ensemble d’outils qui permettent d’étendre les capacités des applications web au-delà de celles des applications traditionnelles, la sécurité et la confidentialité en plus ;
Gecko, le moteur de rendu extensible et portable pour le HTML, le XML et les interfaces graphiques, qui a permis Firefox, Thunderbird et de nombreuses autres applications ;
BrowserID, une technique innovante qui fournit aux utilisateurs et aux développeurs les outils cryptographiques pour assurer l’identification sur le web, sans compromettre la vie privée, la simplicité ou la sécurité ;
les fonctionnalités Mozilla Services de gestion d’identité par le Cloud ;
et d’autres encore…
À propos de vous
Mozilla proposes plusieurs stages dans ses installations à travers le monde sur de nombreux sujets.
Votre profil :
- vous voulez faire du web un endroit meilleur, sur lequel chacun peut naviguer et contribuer en toute sécurité, sans avoir à craindre pour sa sécurité ou sa vie privée ;
- vous souhaitez prendre part à un projet utilisé par plus de 33% de la population du web ;
- vous voulez que votre travail soit utile à tous et visible par tous ;
- vous avez de fortes compétences en Algorithmique et en Informatique ;
- vous avez de fortes compétences dans au moins l’un des domaines suivants :
- systèmes d’exploitation ;
- réseaux ;
- géométrie algorithmique ;
- compilation ;
- cryptographie ;
- analyse statique ;
- langages de programmation ;
- extraire des informations pertinentes à partir de données exotiques ;
- algorithmique distribuée ;
- le web en tant que plate-forme ;
- interactions avec les communautés du logiciel libre ;
- toute autre compétence qui, à votre avis, pourrait nous servir.
- sur certains sujets, un excellent niveau d’Anglais peut être indispensable ;
- les stages sont généralement prévus pour des étudiants M1 ou M2 mais si vous arrivez à nous impressionner par vos réalisations ou par vos connaissances, le diplôme n’est pas indispensable.
Si vous vous reconnaissez, nous vous invitons à nous contacter. En fonction du sujet, les stages peuvent vous emmener à Paris, Mountain View, San Francisco, Toronto, Taipei, ou d’autres lieux à travers le monde.
Les meilleurs stagiaires peuvent espérer un contrat freelance, un CDI ou/et une bourse de doctorat.
Pour nous contacter
Pour toute question, contactez :
- pour tout ce qui concerne les stages chez Mozilla, Julie Deroche (à mozilla.com, jderoche) – Mozilla Mountain View, College Recruiting ;
- pour les stages à Paris, David Rajchenbach-Teller (à mozilla.com, dteller) – Mozilla Paris, Développeur / Chercheur.
October 20, 2011 § 7 Comments
(source: speaker in a recent open-source conference)
And dynamic languages are fun. They make writing code simple and fast. They are vastly more suited to prototyping than static languages. Dynamism also makes it possible to write extremely powerful tools that can perform JIT translation from other syntaxes, add missing features to existing classes and functions and more generally fully customize the experience of the developer.
Or let’s do something a little smarter.
The main benefit of strong, static typing, is that it helps find errors.
- Even the simplest analyses can find all syntax errors, all unbound variables, all variables bound several times and consequently almost all scoping errors, which can already save considerable time for developers. Such an analysis requires no human intervention from the developer besides, of course, fixing any error that has been thus detected. As a bonus, in most cases, the analysis can suggest fixes.
- Similarly trivial forms of analysis can also detect suspicious calls to break or continue, weird uses of
switch(), suspicious calls to private fields of objects, as well as suspicious occurrences of
eval– in my book, eval is always suspicious.
- Slightly more sophisticated analyses can find most occurrences of functions or methods invoked with the wrong number of arguments. Again, this is without human intervention. With type annotations/documentation, we can move from most occurrences to all occurrences.
- This same analysis, when applied to public APIs, can provide developers with more informations regarding how their code can be (mis)used.
- At the same level of complexity, analysis can find most erroneous access to fields/methods, suspicious array traversals, suspicious calls to iterators/generators, etc. Again, with type annotations/documentation, we can move from most to all.
- Going a little further in complexity, analysis can find fragile uses of
this, uncaught exceptions, etc.
Types as documentation
Types as QA metric
While disciples of type-checking tend to consider typing as something boolean, the truth is more subtle: it quite possible that one piece of code does not pass type-checking while the rest of the code does. Indeed, with advanced type systems that do not support decidable type inference, this is only to be expected.
The direct consequence is that type-checking can be seen as a spectrum of quality. A code can be seen as failing if the static checking phrase can detect evident errors, typically unbound values or out-of-scope break, continue, etc. Otherwise, every attempt to type a value that results in a type error is a hint of poor QA practice that can be reported to the developer. This yields a percentage of values that can be typed – obtain 100% and get a QA stamp of approval for this specific metric.
October 13, 2011 § 4 Comments
A few weeks ago, the browser and web development communities started wondering about this mysterious new web language that Google was about to unveil: Dart. Part of the interrogation was technical – what would that language look like? how would a new language justify its existence? what problems would it solve? – and part was more strategic – what was Google doing preparing a web language in secret? where the leaked memos that seemed to imply a web-standards-breaking stance something that Google would indeed pursue? was Google trying to solve web-related problems, Google-related problems or Oracle-related problems?
Now, Google has unveiled the specifications of Dart, as well as library documentation. Neither will be sufficient to answer all questions, but they give us an opportunity to look at some of the technical sides of the problem. As a programming language researcher/designer and a member of the web browser community, I just had to spend some quality time with the Dart specifications.
So, how’s Dart? Well, let’s look at it.
What Dart is
Dart is a programming language and a Virtual Machine. As a programming language, Dart positions itself somewhere in the scope between scripting/web development and application development. From the world of application development, Dart brings
- clean concurrency primitives that would feel at home in Scala, Clojure or Erlang – including a level of concurrent error reporting;
- a clean module mechanism, including a notion of privacy;
- a type system offering genericity, interfaces and classes;
- compilation and a virtual machine;
- a library of data structures;
- no eval();
- data structures that do not change shape with time.
From the world of scripting/web development, Dart brings:
- usability in any standards-compliant browser, without any plug-in (although it will work better in a plug-in and/or in Chrome);
- DOM access;
- emphasis on fast start-up;
- a liberal approach to typing (i.e. types are optional and the type system is incorrect, according to the specifications);
- dynamic errors;
- closures (which are actually not scripting/web development related, but until Java 8 lands or until Scala, F# or Haskell gain popularity, most developers will believe that they are).
Where Dart might help
Web development has a number of big problems. I have
trolled written about some of them in previous posts, and Dart was definitely designed to help, at least a little.
Safety and Code Hygiene
Where Dart might hinder
The single biggest problem with Dart is, of course, its source. To get the VM in the browsers, Google will have to convince both developers and other browser vendors to either reimplement the VM by themselves or use a Google-issued VM. This is possible, but this will be difficult for Google.
The vendor controlled vehicle will be to integrate the VM in Chrome and Android and encourage developers targeting the Chrome Market and Android Market to use Dart. Some speculate that this is a manner for Google to get rid of the Java dependency on the Android Market. In this case, of course, there will be little competition.
Libraries and documentation
Doing it without Dart
Also, while classes and private fields are probably the least surprising techniques for application developers coming to the web, developers used to dynamic or functional languages know that closures and prototypes are essentially equivalent. So, this is essentially a matter of taste.
Isolates are nice. Workers are nice. Isolates are a little easier to set-up, so I would like to see an Isolate-like API for Workers. Other than that, they are essentially equivalent.
String interpolations are nice to have, but not really life-altering. If necessary, they can trivially be implemented by a pre-processor. CoffeeScript might already do it, I’m not sure. Adding this to the JS standard might be tricky, for reasons of backwards compatibility, but there is not much to it.
If we consider I my opinion, there are three ways that Google can get Dart adopted on the web:
- make it the default choice for Android & Chrome development;
- provide a set of killer libraries for the web, that work on all browsers but are truly usable only with Dart (DirectX anyone? something Cocoa-style, perhaps?);
- spend Google-sized budgets on adoption (PR, marketing, GSoC, open-source projects, etc.).
September 21, 2011 § 3 Comments
It’s an exciting time for us Computer Scientists.
Three years ago, I was an academic researcher, studying the best manner to certify binaries uploaded to clouds and ensure their security. Less than three weeks ago, I was working at MLstate, leading the R&D team and striving to change the face of web programming languages and web security. Today, I am part of Mozilla, as a proud member of the Performance team, where we take steps, each day, to make Firefox, Thunderbird and the Mozilla platform faster and more responsive.
We, at Mozilla, have considerable work ahead of us. Because the web needs to be defended, kept open and compatible with privacy, and, on some of these fronts, only Mozilla stands.
An exciting time, indeed – and an exciting way of doing my part!
I will try and blog about ongoing developments as soon as I find a minute.
Edit It seems that I misredacted some of the announces that were sent. Just to clarify, I am not the leader of the Performance team. That person is Taras Glek.
May 30, 2011 § 18 Comments
Feedback from Opa testers suggests that we can improve the syntax and make it easier for developers new to Opa to read and write code. We have spent some time both inside the Opa team and with the testers designing two possible revisions to the syntax. Feedback on both possible revisions, as well as alternative ideas, are welcome.
A few days ago, we announced the Opa platform, and I’m happy to announce that things are going very well. We have received numerous applications for the closed preview – we now have onboard people from Mozilla, Google and Twitter, to quote but a few, from many startups, and even from famous defense contractors – and I’d like to start this post by thanking all the applicants. It’s really great to have you guys & gals and your feedback. We are still accepting applications, by the way.
Speaking of feedback, we got plenty of it, too, on just about everything Opa, much of it on the syntax. This focus on syntax is only fair, as syntax is both the first thing a new developer sees of a language and something that they have to live with daily. And feedback on the syntax indicates rather clearly that our syntax, while being extremely concise, was perceived as too exotic by many developers.
Well, we aim to please, so we have spent some time with our testers working on possible syntax revisions, and we have converged on two possible syntaxes. In this post, I will walk you through syntax changes. Please keep in mind that we are very much interested in feedback, so do not hesitate to contact us, either by leaving comments on this blog, by IRC, or at firstname.lastname@example.org .
Important note: that we will continue supporting the previous syntax for some time and we will provide tools to automatically convert from the previous syntax to the revised syntax.
Let me walk you through syntax changes.
May 23, 2011 § 18 Comments
The Opa platform was created to address the problem of developing secure, scalable web applications. Opa is a commercially supported open-source programming language designed for web, concurrency, distribution, scalability and security. We have entered closed beta and the code will be released soon on http://opalang.org, as an Owasp project .
- Edit The video spawned a conversation on Reddit.
- Edit Interesting followup on Hacker News.
- Edit Reworked source code & comments for clarity. Thanks for the feedback.
- EditCome and chat with us on Freenode, channel #opalang .
If you are a true coder, sometimes, you meet a problem so irritating, or a solution so clumsy, that challenging it is a matter of engineering pride. I assume that many of the greatest technologies we have today were born from such challenges, from OpenGL to the web itself. The pain of pure LAMP-based web development begat Ruby on Rails, Django or Node.js, as well as the current NoSQL generation. Similarly, the pains of scalable large system development with raw tools begat Erlang, Map/Reduce or Project Voldemort.
Opa was born from the pains of developing scalable, secure web applications. Because, for all the merits of existing solutions, we just knew that we could do much, much better.
Unsurprisingly, getting there was quite a challenge. Between the initial idea and an actual platform lay blood, sweat and code, many experiments and failed prototypes, but finally, we got there. After years of development and real-scale testing, we are now getting ready to release the result.