Introducing Jetpack, Call for Participation

Exploring new ways to extend and personalize the Web.

This post has been superseded by the launch of the Jetpack SDK.

The add-ons community for Firefox is arguably one of the largest, most vibrant sources for innovation on the Web today. If you want to affect people, to reach them and make a difference in their daily lives, the Firefox add-ons platform is hard to beat, with over one billion installs of Firefox add-ons to date.

However, we’ve only scratched the surface of its potential.

Today we’re announcing the launch of Jetpack, a Mozilla Labs project to explore new ways to extend & personalize the Web.

In short, Jetpack is an API for allowing you to write Firefox add-ons using the web technologies you already know.

With Jetpack, we’re building upon our experience over the last four years empowering a community of more than 8,000 developers to produce more than 12,000 add-ons to imagine and build the next generation of the add-ons platform. We want to grow our community of developers by orders of magnitude through making add-on creation much more accessible, and yet more powerful by developing it as an extensible platform for innovation itself. Many useful Jetpack Feature’s can be written in under a dozen lines of code.

Specifically, Jetpack will be an exploration in using Web technologies to enhance the browser (e.g. HTML, CSS and Javascript), with the goal of allowing anyone who can build a Web site to participate in making the Web a better place to work, communicate and play.

Most importantly, from a user perspective, Jetpack will allow new features to be added to the browser without a restart or compatibility issues, resulting in little to no disruption to the online experience.

As with all Mozilla Labs initiatives, Jetpack is an open source project and everyone is welcome to participate in its design, development & experimentation.

Initial Release

This is a 0.1 release, so it unpolished, unfinished, and still highly prototyped. We are planning on entirely revamping things for the next iterations within the coming days and weeks. We need your feedback, both on the particulars as well as the direction. In particular, we are actively seeking feedback on the API design.

  • v0.1 – May 2009
    • Initial Jetpack APIs with support for statusbars, tabs, content-scripts, animations, and more.
    • Support for external API libraries (e.g. Twitter)
    • jQuery support
    • Integrated development environment with Bespin, with immediate installs and a fast development cycle
    • Inline debugging with Firebug
    • This initial release of the Jetpack API does not include a fully formed security model. It is being released for testing, development, and feedback.

Getting Started with Jetpack

Developing Jetpack Features with Bespin

Other Resources

Get Involved

Mozilla Labs is a virtual lab where people come together online to create, experiment and play with Web innovations for the public benefit. The Jetpack experiment is still in its infancy and just getting started. There are many ways to join the team and get involved:

— Aza Raskin, Atul Varma, and Nick Nguyen on behalf of the Jetpack development team.

39 responses

  1. Nick wrote on :

    Same as Diego and Franscisco here, on Ubuntu the embedded DroidSans font is displayed as hex boxes. Hope that gets sorted.

    Think it may be a general problem with FF3.5, as this page doesn’t look great for me either:

  2. gwmc wrote on :

    Can someone ‘splain to me why Firefox does not die when the upper right hand x is clicked? After an hour or so of rigorous usage, Firefox turns to shit. Then it won’t quit unless I use Task Manager to kill it.

  3. Diego A. Toala wrote on :

    I have the same problem that Francisco Collao has , i can’t view this webpage

    I’m trying Bespin, nice but I wanna embed one video from youtube , I’m trying to copy and paste the youtube generated code but the copy/paste doesn’t work.


  4. DXM wrote on :

    The fat man is getting fatter….

    (like recaptchas are a deterrent anyway!)

  5. Mauricio wrote on :

    Very exciting to see how these new add-ons will perform and how many new ones we will see since so many people are familiar with HTML, CSS, and Javacript.

  6. Shah wrote on :

    Is there a ogg version that I can download ? is a nice place for non-flash version…

  7. Avindra Goolcharan wrote on :

    Sounds like an awesome version of Greasemonkey with more access to Firefox’s features. Totally looking forward to scripting it here!

  8. Francisco Collao wrote on :

    Hi… nice work for firefox, it’s a easy way for write code for firefox.

    I have a little problem with the jetpack’s page [1], because the ttf, I think is not compatible with ubuntu, I can’t see the fonts [2]. If I delete part of css (@font-face) the problem disapear.



  9. tsyr2ko wrote on :


    Maybe it’s a good idea to implement a fast access to mozStorage for those who also knows web development with php/mysql.

  10. Takis Bouyouris wrote on :

    I am sure it can be greater than GreaseMonkey in potential, but, so far, I do not see anything to this direction. Is it just another way of writing Firefox Addons? Why? There is already a nice way to do this! Is it an easier way to write Firefox Addons? Then how does one deploy their addons? Installing a plugin first which will support JetPack apps is a no-thank-you-very-much-I-hate-this-way kind of way.

    I think the key concept is that an easier way to write Firefox plugins is needed combined with the fact that libraries such as jQuery can be utilized.

  11. Brian King wrote on :

    This is brilliant …. but I am wondering, why the heavy reliance on jQuery and jQuery syntax. It adds another layer of abstraction (and learning) to the JavaScript agnostic types.

  12. Gerhard wrote on :

    I cant wait to get knee deep into this.. 😀

  13. Florian wrote on :

    Btw, I believe chapter 4 is missing in this page : 😉

  14. Patrick Nelson wrote on :

    Absolutely flippin’ awesome!!! It’s perfect, because it’s built FOR the web using native web technologies… before he got to the part about jQuery, I was already asking myself “Hmm, that’s a nice animation — I wonder if he was somehow using jQuery for that?” I love it… Also reminds me of Greasemonkey too (but much better). I love Firefox for all of the extensions and I love you Mozilla for adding this. Thanks a lot! I’m sure it’ll be incredibly useful down the road!

  15. Jeremy wrote on :

    Very exciting to see how these new add-ons will perform and how many new ones we will see since so many people are familiar with HTML, CSS, and Javacript. Hope to see Jetpack by Firefox 4. Wrote a little review on Jetpack on my blog here

    Can’t wait to try it out!

  16. Dom wrote on :

    Very cool! It seems Jetpack combines XUL, Stylish and Greasemonkey, correct?

  17. brandontreb wrote on :

    This is flippin amazing. Can’t wait to start coding…

  18. Jan Jarfalk wrote on :

    When will Jetpack be in Firefox by default? Until then its just Mozilla JetGreaseMonkeyPack without all the zillion extensions.

    Please make it a part of Firefox… I would love to unlearn XUL.

  19. Melvin Ram wrote on :

    Damm. I was using Jetpack as the name of my open-source Rails starter application for a few weeks now. This sucks. It will now be confusing to people.

  20. Daniel Hough wrote on :

    This is super cool guys! Easier than Greasemonkey too 🙂

    Here’s the first thing I’ve made: a mod for Facebook so you can use your name inside your status:

    Been wanting to do it for ages, thanks for making it easier! 😀

  21. Dimas wrote on :

    Very cool, would like to see a comparison article about JetPack vs GreaseMonkey …

  22. Tyler Mulligan wrote on :

    Awesome work guys, I’m excited to try this out. XUL can get a little confusing by comparison.

  23. tunpishuang wrote on :

    sounds good,i’d like to dev. an basic extension for jetpack.

  24. Girish wrote on :

    WOW , I am going to write about this in my blog.

    this is cool.

  25. Wahooney wrote on :

    This is really cool 😀

    Are there docs somewhere that explains how to get bespin going in about:jetpack?

  26. AD wrote on :

    Have I missed the point of JetPack or something? It just appears to be a client based, and is made for users; there is not one example of it being used as part of a website, for a website; or indeed to improve on a website’s usability; its just a tool to make your web/user experience a bit more flashy… well how does this help me? It doesn’t.

  27. Wahooney wrote on :

    This is a great plugin! How do you get bespin in there though?

    Is there a step-by-step instruction for that or is one forthcoming?

  28. Puneet wrote on :

    Looks nice. 🙂

  29. Jeremy wrote on :

    Is it just me, or does Mozilla always ooze awesomeness?

    Looks great, I can’t wait to see some of the tools.JQuery combined with this just adds an infinite number of possibilities.

  30. Gary wrote on :

    This is fantastic! I look forward to version 0.2 and eventually a full release. This is a great way to add more functionality into Firefox and make it even more powerful.

  31. Artem Russakovskii wrote on :

    Sounds exactly like GreaseMonkey. Is it just a push in the similar direction with Mozilla behind it?

  32. Bob Chao wrote on :


    I don’t think so, with Jetpack’s API developer can do more (in theory) than Greasemonkey. This could be a good response for Google Chrome’s new-annonced extension framework, and more.

  33. tamnghien wrote on :

    Cool.Like Greasemonkey but easy to develop and manage.But is there any feature to import Greasemonkey’s script ??

  34. fred wrote on :

    Why all the flash videos?

    Come on now. I’m running Mozilla 3.5b4 to avoid all that stuff.

    How about posting the videos on this page in ogg on or somewhere.

    Very disappointing.

  35. Sam wrote on :

    Awesome, love it! 😀

    One question though, how can I make it so that when the popup comes up in the corner, when you click on it it goes to a website (ie twitter, facebook, etc.)?

  36. David wrote on :

    This is Huge.
    Thanks for the ongoing innovation at Mozilla!

  37. sunny wrote on :


  38. Casey wrote on :

    How is this any different from Greasemonkey? Aren’t you just risking taking development resources away from them and their community when they already have something great in place?

  39. Jason Huggins wrote on :

    This is very, very cool! No more RDF files!