The web is getting darker. It is being weaponized by trolls, bullies and bad actors and, as we’ve witnessed, this can have extremely grave consequences for individuals, groups, sometimes entire countries. So far, most of the counter-measures proposed by either governments or private actors are even scarier. The creators of the Matrix protocol have recently published the most promising plan I have seen. One that I believe stands a chance of making real headway in this fight, while respecting openness, decentralization, open-source and privacy. I have been offered the opportunity to work on this plan. For this reason, after 9 years as an employee at Mozilla, I’ll be moving to Element, where I’ll try and contribute to making the web a better place. My last day at Mozilla will be October 30th.
On this rainy october day (well, at least it rains where I’m writing this) of the great year 2020, let’s take another few minutes to reflect on some great practices that we have at Mozilla and that would deserve to take over the world. Today, let’s talk about what you can do when your work is blocked.
Let’s continue this series on some of the great practices that we have at Mozilla and that your project may wish to adopt, too. This time, let’s talk about Mozilla’s #introduction chatroom.
2020 is a crappy year for pretty much everyone. As you may have seen, this includes organizations such as Mozilla. So I figured it was the best time to actually talk about good stuff! This entry should be the first of a series of short articles dedicated to some great practices we have at Mozilla and that I think many open-source projects could adopt. At its core, Mozilla is a community of open-source enthusiasts. When you’re new to an open-source community and you wish to start contributing somewhere, finding an entry point is often difficult. This is where Mentored Bugs come in.
TL;DR: Firefox used to have a great extension mechanism based on the XUL and XPCOM. This mechanism served us well for a long time. However, it came at an ever-growing cost in terms of maintenance for both Firefox developers and add-on developers. On one side, this growing cost progressively killed any effort to make Firefox secure, fast or to try new things. On the other side, this growing cost progressively killed the community of add-on developers. Eventually, after spending years trying to protect this old add-on mechanism, Mozilla made the hard choice of removing this extension mechanism and replacing this with the less powerful but much more maintainable WebExtensions API. Thanks to this choice, Firefox developers can once again make the necessary changes to improve security, stability or speed. During the past few days, I’ve been chatting with Firefox users, trying to separate fact from rumor regarding the consequences of the August 2020 Mozilla layoffs. One of the topics that came back a few times was the removal of XUL-based add-ons during the move to Firefox Quantum. I was very surprised to see that, years after it happened, some community members still felt hurt by this choice. And then, as someone pointed out on reddit, I realized that we still haven’t taken the time to explain in-depth why we had no choice but to remove XUL-based add-ons. So, if you’re ready for a dive into some of the internals of add-ons and Gecko, I’d like to take this opportunity to try and give you a bit more detail.
A number of programming languages offer a feature called “Named Arguments” or “Labeled Arguments”, which makes some function calls much more readable and safer. Let’s see how hard it would be to add these in Rust.
Years ago, Andrew Kennedy published a foundational paper about a type checker for units of measure, and later implemented it for F#. To this day, F# is the only mainstream programming language which provides first class support to make sure that you will not accidentally confuse meters and feet, euros and dollars, but that you can still convert between watts·hours and joules. I decided to see whether this could be implemented in and for Rust. The answer is not only yes, but it was fun :)
If you’re reading these lines, you may have recently been laid off from your job. Or maybe, depending on your country and its laws, you’re waiting to know if you’re being laid off. Well, I’ve been there and I’ve survived it, so, based on my experience, here are a few suggestions:
Credit While I’m the author of this blog post, 99% of the work was done by Nicolas B. Pierron. So far, my role in this project has largely been to play the wise old advisor, nodding and smiling mischeviously whenever Nicolas started exploring new ideas, and emitting cryptic comments in Reverse Jedi Notation. A few months ago, we published a short (and mysterious) blog post in which we mentioned HolyJIT, an early research project towards a novel approach to writing JITs. In this blog post, I would like to detail a bit more the ideas behind HolyJIT.
In this entry, I’d like to discuss one of the most interesting and unusual aspects of the Binary AST: how we gain performance by turning proof-building into validation, and why this is very good news for performance (and maybe not so good news for file size).