SpiderMonkey

Last week we introduced what import maps are and how they work. This week Yoshi explores the feature in depth, in the second part of his two part series on Import maps. Read the blog post here: spidermonkey.dev/blog/2023/03/0…

Late last year, we implemented the Import Maps specification in Firefox. Yoshi (the engineer working on it) wrote an in-depth introduction to it, along with a deep dive that you can expect next week! Read the blog post here: spidermonkey.dev/blog/2023/02/2…

SpiderMonkey Newsletter (Firefox 106-107) spidermonkey.dev/blog/2022/10/2…

SpiderMonkey Newsletter (Firefox 104-105) (Mozilla JavasScript engine) spidermonkey.dev/blog/2022/08/2…

SpiderMonkey Newsletter (Firefox 102-103) spidermonkey.dev/blog/2022/06/3…

Ecma International recently approved the 2022 standard of ECMAScript. But there is something new in this edition that hasn't been part of prior editions, and this isn't a new programming feature. 🧵 hacks.mozilla.org/2022/06/the-sp…

[Firefox JS engine] SpiderMonkey Newsletter spidermonkey.dev/blog/2022/03/1…

SpiderMonkey Newsletter (Firefox 96-97) spidermonkey.dev/blog/2022/01/1…

@fvsch Thanks for the report! I filed bugzilla.mozilla.org/show_bug.cgi?i…

var err = new Error(); Object.defineProperty(err, 'stack', { value: 'hello', writable: false }); Object.defineProperty(err, 'stack', { value: 'goodbye', writable: false }); Chrome: I’ll allow it. Firefox: Uncaught TypeError: can't redefine non-configurable property "stack".

Who can I talk to about Firefox erroring when code tries to define an Error's stack properties twice? Seems to be standard-compliant but V8 doesn't, so Node libraries do it all the time and can't run on @SpiderMonkeyJS. 😭🙈

My team at Mozilla is hiring. Come write compilers with us! The Layout, DOM, and Media Playback teams are also looking for C++ programmers: careers.mozilla.org/position/gh/35… Happy to answer questions if you're interested!

[JavaScript Engine] SpiderMonkey Newsletter (Firefox 94-95) spidermonkey.dev/blog/2021/11/0…

Following @codehag 's footsteps with #CompilerCompiler, this Firday 6pm CEST would be the first #ReverseEngineerSpidermonkey stream at twitch.tv/BackToTheCode. On the topic, the LifoAlloc allocator used to speed-up large number of allocations while reclaiming the memory quickly.

SpiderMonkey Newsletter (Firefox 92-93) spidermonkey.dev/blog/2021/09/1…

I've finally setup my blog - dbezhetskov.dev/blog and there is a first post about SpiderMonkey and WASI (dbezhetskov.dev/blog/spidermon…)

A lot of improvements landed in Firefox 90 and 91. Read about it in our latest newsletter: spidermonkey.dev/blog/2021/07/1…

ECMAScript excitement 😉 Congrats to all those who contributed to today's release of Firefox 90 🎉 ⚡ Private Fields & Methods (Stage 4) ⚡ .at() for Arrays & Strings (Stage 3) ⚡ Ergonomic Brand Checks (Stage 3) ⚡ Intl.DateTimeFormat dayPeriod option

Our friends @SpiderMonkeyJS implemented the Error cause proposal in Firefox 91* (github.com/tc39/proposal-…) The WebConsole displays this new cause property in error messages (and yes, you can have a chain of Error causes 🙂) * 91 will be Beta/DevEdition later this week

Just-In-Time (JIT) compilers are used in all major JavaScript engines to improve the speed, but how do they work? At Global Scope @nbpname will help us understand the principles of JIT compilation, and so how to optimize our code. buff.ly/3dkGzhL

Language specification can be a bit of a mystery. At Global Scope, @codehag introduces the stages of the TC39 process for introducing a new language feature to JavaScript, and some high level concerns around our design process. buff.ly/3djR3OE

@littledan @andywingo @SpiderMonkeyJS @luke_wagner @codehag Honestly, hiring John Howard for any JS engine swag design is now mandatory. The BaldrMonkey t-shirt is my favorite 🔥 monkeyink.com/ink/blog/archi…