Calendar Project at a critical juncture

The Calendar project, which for several years has been working on the Lightning add-on to Thunderbird and the standalone Sunbird project, is at a critical juncture. We feel it’s important to communicate this to our users and contributor community, as your input will determine how the project continues.
Recently, several contributors who were working on the project full-time have left the project or have shifted to free-time contributor status due to other obligations. This means their contributions will be limited to their spare time, which is quite sparse given a full-time job and family. This is a significant change from recent years, and if no new contributors come on board, it means that the rate of change will decrease dramatically. Our releases will necessarily have to become less frequent, and the amount of bug fixes and new features per release will decrease.
As a result of this, we have to take stock, and figure out how we’re going to go forward.
First, as much as it pains us, we have decided to step back from Sunbird maintenance. Our next release will include Sunbird, but subsequent releases won’t unless new contributors take on the work. Trying to support both takes too much time, so we had to make a painful prioritization decision.
Second, our next major goal is to have a version of Lightning that will work well with Thunderbird 3. Lightning won’t be built-in to Thunderbird 3 for a variety of reasons (see this post by David Ascher for more on the topic), but we’re still on track to have a release that gives users of Thunderbird 2 & Lightning a migration path. That version will be a significant upgrade from Lightning 0.9, including notable performance and usability improvements.
There’s a lot of work to do to reach our goals, and as a result we’re not yet planning much beyond that. This is where we need your input, both in terms of direction-setting — given limited resources, where should we focus and why? and in terms of more directly useful help — if you’ve been using Lightning for a while, and know a bit about mozilla technologies (any of XUL, JavaScript, CSS), or want to help test, write documentation, or do something else not listed here — get in touch!
This is really a tremendous opportunity for anyone who is interested and willing to help make a difference here for the project and its hundreds of thousands of users — get involved!
I hope to hear more from you soon!
Philipp Kewisch (Calendar Project – lead developer)


  1. Could you make the next version of Lightning work on Ubuntu? I really miss my integrated system. I’ve got a custom build of Sunbird I found on the web, but I’d really rather have something supported.
    My next request would be complete integration with Google Calendar.
    Other than that, I love it just like it is. Thanks for all of your hard work!

  2. Hi Philip,
    I wish I could spend time on development but I am tied with my family and full-time job. However, I try to test the nightlies and try to file report issues as I find them. As far as the future progress here is my feedback:
    – I’ll be happy if the calendars were refereshed faster. I know there were some bug fixes which improved the refresh rate but it is slow once you have a highly dense calendar.
    – Calendar alarm notification via. e-mail. I know there’s some progress in that. But looks like it is not going to happen for release 1.0
    – The today pane when in mail mode
    – The ability to configure a background image (I have done it via. creating some css code in userChrome.css). But an option via the menu would be more user friendly
    I know there are several other features that many other users need but for my day-today use these are sufficient enough.
    And if it helps others I use dropbox to share my calendars between computers (at work and at home). It is pretty good. Has got secure access to file storage.
    Hope we don’t lose any more people from the project.

  3. Hi,
    you suggest that you would appreciate input in terms of direction setting (perhaps debate?) so here is mine:
    My first reaction to David Ascher’s post is to thing that you might be better off keeping sunbird rather than lightning. Because:
    1) thunderbird has struggled somewhat to prove that it is/will be an email client of choice and the post suggests that there is some doubt about progress, i.e. “the calendar team has had a tough time of figuring out how Lightning needed to change to integrate optimally in Thunderbird… Thunderbird’s interface model is still shifting…”
    Thunderbird also seems a bit ambivalent about the central importance of lightning “more generally, we recognize that different users need different kinds of calendaring solutions”.
    Does it make sense to tie the future of the calendar project to the future of untested software ? (I’m not intending to be overly critical of thunderbird – I do use it sometimes – but the fact is that it hasn’t yet become the great piece of software it could).
    2) If thunderbird is successful and sunbird continues to develop into a very nice calendar option that it is becoming, then wouldn’t it make sense for the much better resourced thunderbird to put in the resources to develop an integrated add-on if that what they perceive as important?
    So I personally wouldn’t give up on calendar as an independent piece of software. I would continue to focus on those aspect of the calendar that already do, and will, make it attractive to users (I perceive enormous progress to date):
    1) nice calendar interface
    2) ability to set appointments on an office environment (microsoft exchange??).
    3) perfect interface for google calendars.
    4) ability to synchronise with handheld devices and phones.
    5) Expanded task management (sub tasks, progress indicators, etc)
    6) a strong contact book (I’d actually make this a 3rd separate project that would interface with both sunbird and thunderbird because both need it a keeping tract of contacts is a hugely important job, not an addon).
    I’d model the project on Apples mail,cal and address book programs that are separate but allow interactivity on things like using emails to set appointments in the calendar (maybe once thunderbird has worked out what their interface will actually look like they could implement this). Modelling is important but Mozilla does not need to model outlook.
    Gosh – hope that doesn’t come across too strong – you are the developers! Thanks for communicating so openly.

  4. Hola:
    Soy desarrollador web y tengo habilidades bastante avanzadas con CSS y JavaScript.
    No quisiera que el proyecto se perdiera, así que si puedo ayudar en algo, estoy disponible.
    I’m a web developer and i have some advanced skills on CSS and JavaScript.
    I really want to contribute, so if can i help with somethin, i am aviable.
    Sorry if i made some mistakes with my english.

  5. Bad news !
    The stand alone sunbird is more important than lightning.
    There is no need to integrate the calendar in to thunderbird. A lot of time wasted.
    The community users wrote there wishes often enough on this board: PDA-SYNC, more performance, serverless multi user, part export of calendars – nothing happened.
    And now sunbird shouls be stopped?!
    Than you can stop lightning, too.
    Most users will use other products.

  6. Hi,
    here is some thought I’ve about the calendar project, I already talk about it a little bit when 0.9 was release, but it’s worth telling it again here.
    I actually did wanna involve in the project in Mars – June 2008, but I was to much deceived about the 0.8 release (which is the first release that I’ve really followed, and started to test from the beta) on a management point of view, one of the reason was from decision that has been made to ship with some blocker not resolved, and then 0.9 that has been tested less than a month and their was still a lot of bug, on which some should have been blocker and then I had to go back to 0.8, since 0.9 wasn’t usable enough (see comment 2 )
    next about release rate how can you hope to have I well tested app when you release so fast:
    0.8 final – 4 april
    0.9 beta – never found one in the blog (was there a beta?)
    0.9 RC1 – 11 sept
    0.9 RC2 – 19 sept
    0.9 final – 23 sept
    if you to do ‘major’ release often it’s good, but test it carefully, you had 3 release in less than 15 day, the calendar project have a small community tester so the testing time should be way longer, look at firefox and thunderbird, they have more than a month between every release and they have a huge testing community, so when they release their final, it’s almost bug-less (at least nothing that might have been blocker) and every release is a great release (meaning, better than the older one). Calendar didn’t have one great release since I know about it(0.5), there is always some bug that make calendar unusable for some user, and these bug are never resolve before the next release.
    so now that the main development team is reduced you must review your way of testing/releasing and then give quality to user instead of just a bunch of new functionality that are half working
    that being said, I think that if you can have a great 1.0 release, you would get a lot of new user(look in the news group how many people just need one feature, that has been promised for some release but is still not there, to use that app) and a few more needed developer (that just don’t wanna involve because the project seam to go nowhere or some other reason)
    one note about stopping one of the product support, there is one good decision, calendar team is too small to support 2 ‘project’ and since 0.8 there are way to much difference between lightning and sunbird, now should we drop lightning or sunbird I don’t know but one must be dropped.
    now about what should be worked out first I’m not gonna say what I need but just where you should look to know it (but I’m sure you already know it) the vote in bugzilla give what the involved community want, the comment in the news group about functionality needed or really annoying bug, and this blog that is followed by people interested in the project. So when you see a lot of people talking about one thing that should be done, do it for the NEXT release, not some future release.
    I hope you understand my point, and that calendar project is gonna evolve in a good way

  7. Don’t give up !!!
    Thunderbird needs you.
    Calendar is #1 requested feature in Thunderbird 3.
    Push as hard as possible to integrate Mozilla Messaging.
    IMHO Thunderbird gets big added value from your extension, it would be fair that Mozilla Messaging give you back some support.
    In your opinion, did you get so far enough support from Mozilla Messaging ?

  8. In my organisation it is only the combination of Thunderbird and Lightning that makes a package that is acceptable as an alternative to Outlook in the eyes of the average user.
    Please do not give up on lightning.
    Now that Google and Lightning support CalDav format it has become possible to sync easily with Google Calendar, although it would be better if an easy to use user interface for setting up the link was available.
    Other than that – as soon as the “Cached Mode” is declared stable I will have most everything I need.

  9. Of course it’s very had, to choose between Sunbird and Lightning. I can only speak for myself, but the choice for Lightning was good. Calendar and Mails are way better in a single Application. I’m sure, if the Thunderbird 3 finally comes out, you and Thunderbird will get a boost in support from the Community.
    For directions of Lightning:
    I would like to see the focus on Synchronization, Plattform independent use and Stability. New fancy features or beautiful interface are less important to me than a productive and stable Application.
    Good Luck! :)

  10. Hi,
    a few thought about SB or LG.
    Think ‘djo0012’ stated it very well:
    >>there is one good decision, calendar team is too small to support 2 ‘project’ And I understood TB3.x will be similar.
    So the bad question: what’s about the ‘calendar’ project with that opportunity?
    — Is SB similar to that concept?
    — Can LG 1.x be installed ontop of FX/TB/XLrunner?
    Looking forward to get an answer for that.

  11. You should definitely concentrate on sunbird rather than lightning. Who wants bloatware?

  12. Hi,
    Firstly, thanks to all the devs past and present of Lightning / Sunbird for a great product(s). I have been following the nightly progress since 0.8.
    As noted by all, to choose between the two is extremely difficult, but I think you have made the right decision. I think the future of both Lighting and Thunderbird are heavily reliant on each other. Even though not every Tbird user wants an integrated calendar, I think it would be naive of the Tbird devs to think that Tbird 3 will be a winning product without the ability to have some sort of calendaring available.
    To that end, I think Lightning should remain available as an add-on only and not be integrated directly into Tbird, but Mozilla Messaging should invest some of their manpower on Lighting to ensure the most seamless integration possible for those who use it, and the two products should be developed in combination.
    Keep up the good work, and know that there is a lot of user support for all that you are doing (both Lightning / Sunbird and Tbird 3)

  13. Hello
    It’s the 1st time I post here and I just want to say a couple of things.
    Lightning is great product and it’s absolutely an indispensable addon for Thunderbird. Without it Thunderbird cannot compete with any other full featured mail client with calendar, M$ Outlook for first.
    Precisely for this I think that Mozilla Corp. whould be made aware of the importance of this project and the risks that its possible death would involve.
    Mozilla created Mozilla Messaging to promote and sustain Thunderbird; I think that the Calendard projects has to be fund by Mozilla as they do for TB.
    Maybe I’m saying inexact things but if really Mozilla is so “out” of the life of the Calendar project then I suggest the developer to write to them and ask for funds. Mozilla cannot receive millions of $ by Google and benefit of the Lightning popularity without consistent support.
    IMHO, of course

  14. I agree with many here that although a stand-alone calendar is great, the amount of good a solid calendar plug-in for Thunderbird does far outweighs a stand-alone calendar program. I’m surprised that Mozilla seems to not get this. Whenever I show people Thunderbird, one of the first things they ask is, “Where’s the calendar.” Or if it’s in a business situation, “How to I connect it to Exchange.”
    My advise would be the following:
    1) Focus on Lightning, but whenever possible keep the code base just a few stone throws away from being able to be packaged as a stand-alone app.
    2) Focus efforts on stability, speed, and interoperability–in that order.
    We don’t need a ton of one-off features that fit niche needs. I think a good mantra would be to focus on features that fit under the “interoperability” umbrella. Google calendar, exchange, synchronization with mobile devices, etcetera, these are new features that will make Lightning/Sunbird more attractive to more users.
    Keep up the good work though. Don’t give up! Probably not coincidentally, I’ve noticed several open-source projects I’ve been following also struggle as of late. I think that as economies in the world contract, so does people’s discretionary spending as well as donations (which I consider contributing to an open-source project to be a part of).
    I think things will turn around. But taking steps to triage development goals at this point is healthy.

  15. Hello,
    First of all, thank you all for the amazing work you’ve done for Sunbird/Lightning/etc., I’ve been following your project for a while and I enjoyed Lightning while I used it in Thunderbird. I’m now giving Postbox a spin due to the very slow development of Thunderbird 3, but I certainly miss having calendaring and email integrated in one application.
    I agree with the sentiment that Mozilla should step up and give you guys the attention your project deserves. Be it through a grant, being adopted by Mozilla Labs, giving you dev time from their main team,… I don’t know, something.

  16. Without Lightning I would be looking for a new mail client.
    The future of collaboration is not e-mail but a more semantically aware messaging environment. Integration with other tools and the ability to schedule time are key.
    Time for the Thunderbird team to stop polishing and start redefining the collaboration experience.

  17. Thunderbird without Lightning is completely useless:
    * most individuals prefer webmails
    * all corporate users need a collaboration platform, not only a mail client.
    I hope the MoCo and/or MozillaMessenging will understand the Calendar project is a crucial piece of software, and that you’ll get the financial support you deserve.

  18. djo0012
    I wouldn’t consider an RC (release candidate) to be a separate release. We didn’t do 3 releases in 15 days, we did one release on April 4th (0.8) and one one September 23rd (0.9). Nothing speaks against handling releaes different than Firefox and Thunderbird. For us, a release candidate is a way to increase public visibility and testing in preparation of a final release. Given the small amount of developers we had and also the amount of manual work for release engineering needed for an rc or major release, it didn’t make sense to do releases/rc’s more often.
    I am aware that our testing community is not that large, but please remember our code is not as mature as Thunderbird or Firefox. We would have loved to fix all the bugs that make the product unusable for some kind of user, but there is always a tradeoff between:
    * release often
    * make release not have many bugs
    * add missing features
    We can’t do all at once. If we don’t add missing features, casual users will think we aren’t doing anything, since the UI doesn’t change at all, or people will complain that “just that one feature” is missing for them to use the product. If we fix all bugs proposed for a release, then we probably won’t be able to release more often than once every 1-2 years, which will also give users the feeling that nothing is happening.
    I understand that its aggravating if certain features you look forward too are not part of the next release, but unless more people get involved in the project it won’t be possible for us to satisfy all kinds of users at once, since some feature will always be missing.
    Maybe you are interested in helping out to fix just those features you’d like to see in the next release?
    Ian Eiloart (also answers parts of cheekybuddha’s comments)
    Of course nobody wants bloatware. But the goal is to make Lightning in Thunderbird as performant as possible and the interface as lean and mean as possible. Ideas we’ve had include making Thunderbird+Lightning give you the choice if you’d rather want calendar or mail. This way, mail won’t get in the way and bloat the application if you only want calendar, but if you’d like to send invitations via email, you can still set that up without needing a different application.

  19. Danilo Fortunato

    Here is my humble opinion about the forced choice between Sunbird and Lightning.
    I understand that, having calendar functionalities togheter with e-mail functionalities, is an attractive option – after all, Lotus Notes and Microsoft Outlook provide exactly that.
    However, I’d like that the Calendar project focus on Sunbird, instead of Lightning.
    In my opinion, it is much better to have a good and stand-alone calendar program, like Sunbird.
    If you want to use e-mail and calendar, you can just run Thunderbird and Sunbird – it is not the end of the world.

  20. Put this on the main page,
    so more people find it.

  21. @Philipp
    > I wouldn’t consider an RC (release candidate) to be a separate
    > release. We didn’t do 3 releases in 15 days, we did one release
    > on April 4th (0.8) and one one September 23rd (0.9).
    sorry your right, I was talking about testing release and the time you give for tester to do a good job and to see bug that are currently present
    in comparison:
    -Firefox have hundred of thousand of tester and they have 1 to 3 month between every beta
    -thunderbird probably have a few thousand tester as well, stil they have 2-3 month between every beta
    -calendar I’m not certain if you have one hundred tester and you do no beta (as I found), 2 rc and the final “stable” release in less than 15 day.
    yes the project is smaller, yes you cannot do more release, I’m just talking about more spacing the testing release so a least you know pretty much all the bug that the end-user will encounter (and then maybe tell it in the know issue…) but now it doesn’t even worth testing the rc and then filling bug since we know it’s not gonna be corrected before the next major release.
    I understand that calendar team prefer to have a release often way of working, ok it’s a way of working and it’s legitimate, but by doing that you send a product that has to many issue and after i 15 minute testing a end user that has seen 1 or 2 of this issue will say “it’s a good product but unusable at the moment, might come back next release if I didn’t find good enough for me a that time” going with that is the development staff you would like (and need) to have that is going on another project.
    so all I’ve to say is do stable release or no release, it’s just gonna help you a lot (by first getting you in the thunderbird cause stability is probably one of the main reason why your out)
    I’ll stay their before repeating myself again and hope to get something good next time.

  22. More Mozilla support for Lightning!

  23. Personally, I don’t use Thunderbird, but I do use Sunbird on my Linux box, so I’m very saddened to read this. I hope that some new contributors step forward so that Sunbird can continue to be supported.
    One suggestion I have would be to drop support for Sunbird on the Mac (and maybe Windows), but keep supporting it on Linux. Face it, Mac users are going to iCal, not Sunbird, so you could save some resources (testing and building) by dropping Sunbird for the Mac at least.

  24. Late to the party as I’ve been traveling but my main thought is that I would like to see better syncronisation support. The Google Calendar provider was great and now that Google Calendar supports WebDav and Sunbird officially its even better. Ensuring that this continues to work well and better in the future is very important to me. I use numerous computers and this feature is a must. Also being able to sync with my phone would be great as well. Calendar everywhere basically!.
    I hope you get more contributors for this great project, I’d love to help out but with full time work and part time university doing a thesis I barely have time to sleep.

  25. Promote sunbird better (for example on the startpage of and try to get more users to donate.
    Or make sunbird shareware, i.e. a basic freeware version and an extended commercial version, i.e. with a lifetime license for 30-50 USD.

  26. Please, don’t kill the sunbird…
    Not now when we is coming to 1.0 …
    Please Philipp Kewisch
    Create a mozilla_sunbird on the getsatisfaction (mozilla account)
    Firefox ( )
    Thunderbird ( )
    With that we can provide more feedback to the project.

  27. Why not deliver the project to P.O.T.I from the same of songbird and make then a subsidiary.
    I think they have more money too buy and test palms and cellphones with calendar…

  28. Hello, Philipp.
    I am interested in development of project calendar.
    Now I work with a feedback-document, possibly for me will turn out to interest some people from with programming-skills which will want to work with me.
    I am from Ukraine, and badly speak English, but I hope that it will not prevent our further collaboration. (I can read, but have problems with exposition of the words in your language)
    Answer to mail:

  29. Hello, Filip.
    I am very interested in development of project calendar.
    I have skills of management, raising of requirement specifications, and drafting of project document, projects.
    Now I work above a technical-document for the calendar-team. Possibly for me will turn out to interest some people, able to programing (from, which will want to work with me.
    (To me most interested integration calendar with SeaMonkey and some elements of CRM, similarly in this document some errors and wishes are included appearing before in bugzilla, but all is formed in a complete tech-doc)
    I am badly speak English (I can read but have problems with exposition of the words in your language), but I hope it will not prevent our further collaboration.
    answers to:

  30. I would recommend you continue with Sunbird as a separate calendar program. Most organisations have established email clients and corporate managment strategies will not provide multiple email clients on the users desktop, so thunderbird dependency is a problem. By providing Sunbird you enable users to co-ordinate time & date based activities across networks of independent organisations and a significant exemplar of a mozilla community development. The means to browse and search multiple calendars is extremely useful.

  31. I liked Lightning enough to make a donation!
    I agree with the earlier posters that Thunderbird + Lightning makes a nice open source alternative to Outlook that lets you aggregate your various communication platforms into one.
    I don’t really want yet another application running on my desktop if Lightning can do the job as a plugin.
    I was happily making Thunderbird the aggregation point for all email and calendars when I ran into the bugs that prevent multiple Google calendars using Lightning.
    I would love to join with people to provide a bounty.
    Is there any interest?
    Here are the bug ids:

  32. I wish I could support the project more, but I am merely an (extremely appreciative) user. FWIW I prefer using a stand-alone calendar. At home, I just prefer it, but at work it is for more practical reasons. We have Outlook forced upon us, and I like to maintain a completely secondary calendar for my daily and long-term lesson plans (I’m a teacher) and for personal appointments. Having to launch a completely separate email client just to access a plug-in would make this cumbersome.
    Whatever direction the project takes, I’m looking forward to what you talented people can do.

  33. We recently moved to calDev. I was thinking of using SunBird instead of Lightning. When I was looking for SB add-ons came across this blog. I know this is a bit old but I though I would submit my feedback anyway.
    I do not need calendar all the time. Specially after office hours but I do need email. TB+Lightning takes a lot of memory. With SunBird I could choose not to use Calendar. The only problem I found with SB was lack of integration with LDAP. In my opinion, with LDAP integration there will be lot more SB downloads.

  34. I just installed Lightning into SeaMonkey 2. It integrates beautifully into the Suite concept. The “Calendar” tab looks very familiar for someone used to Sunbird, and the additional pane in the (now) 4-pane MailNews tab is a GoodThing™.
    Too bad, though, that Sunbird will have to be discontinued (or already had? AFAICT it is not being built anymore). The above posts show that it will be missed. Let’s hope someone will pick it up off the floor, the way SeaMonkey was picked up when MoFo dropped the Mozilla Suite.

  35. Please consider Sunbird more important than Lightning.
    I want to move away from Thunderbird because of a major design flaw. TB puts into a single file all the mail in one folder, so that when Kaspersky jumped on a virus in one email recently, my wife lost a whole folder of email.
    But the calendar is excellent, and I don’t want to have TB up and running just so that I can use the Lightning extension.

  36. I would really like to get a copy of Sunbird 1.0b1, so that I can have a calendering app that remains running without the need for a browser. So many things (mainly Flash) crash the browser, and I just can’t see attaching my calendar into that mix.
    Could someone kindly post the status of Sunbird – will we ever see a 1.0b1 build? If not, is there a way to get a Google provider for SB .9? I just tried installing the .6b1 provider, and it says that it will only work with Sunbird 1.0b1

  37. I agree with previous posters.
    Don’t give up on Sunbird.
    I use it far more often than lightning in Thunderbird.
    If one has to go make it lightning!

  38. I can’t believe I missed this announcement for so long. I am user of both Thunderbird and Sunbird. I know I could use Lightning within Thunderbird but one of the reasons I chose to use Thunderbird was that I could use Sunbird separately. This decision was based on a family need rather than a personal one. If the idea is to copy Outlook, I might as well use Outlook since others in my family are more experienced with Outlook. If Sunbird goes away, I will continue to it until it becomes incompatible with my OS or google calendar. At that time Mozilla will probably lose another user (TB, Sunbird and FF) because I try to keep all of our computers consistent for simplicity’s sake. Right now Sunbird is the lynchpin that keeps us with Mozilla apps. If I lose that, I will not be able press the others.
    Reality is what is, so if Sunbird is mothballed I will understand but be very disappointed.

  39. I use Sunbird 0.9 @ my work. I am realy looking forward to the new 1.0 release! because it fix the anyoning printing bug!