Interview: Tobias König about the development of Akonadi

Tobias König auf den Chemnitzer-Linux-Tagen 2008 mit Konqui auf der Schulter in conversation with Tobias König

Translations are available in: Italian (thanks to and Polish (thanks to The german original can be found here.

Tobias König is a Computer Science student and one of the core developers of Akonadi, one of the innovative technologies that will be implemented in KDE4. Akonadi will be a platform independent innovative storage solution for personal data. In this interview, Tobias König shares his impressions about the integration into the KDE desktop environment and Akonadi's development and features. You are deeply integrated into the development of KDE. What kinds of things do you spend time on when you do not work on that?

Tobias König: I study Computer Science at the HTW Dresden while I am not busy with developing KDE. I also work as a freelancer for credativ GmbH. What is credativ GmbH and what are they offering?

Tobias König: Credativ GmbH offers services around open source software solutions. The majority of coworkers come from the open source environment, as from the debian project or from postgres. There are also a couple of people from KDE :). One could say, you made your hobby your occupation?

Tobias König: Yes, one could say that :). However, I am mainly a student for the next 2.5 years. This means that you are 24/7 busy with open source packages ;). Could you tell us which KDE projects you are participating with? For which tasks have you taken responsibilities?

Tobias König: My home is the KDE-PIM project. This is the subproject for KDE which is focused on personal information management. This encompasses calendars, address books and e-mails. In addition to the management of KAddressBook, I also help with the development of Akonadi, the new system for PIM storage. During the time KDE3 was ported to KDE4, I also supported the development of the core libraries for KDE. Akonadi is a good topic. Could you explain what Akonadi is in detail? Is it not true, that already now, there are too many groupware solutions, all promising to deal was any possible data types?

Tobias König: At first the most important: Akonadi is not a groupware server! In contrast, Akonadi is an intermediate storage and abstraction layer for PIM data. This is similar to Phonon, for multimedia or Solid for hardware. Akonadi abstracts the access and maintenance of data for the rest of the system (i.e. the address book or the calendar). This is achieved by offering a common interface for all the data. In turn there are several improvements in comparison to KDE3: 1. PIM data must only be held once in the memory 2. There is a central instance which monitors any change of the data and hence informs all other components about it. 3. The whole Akonadi framework follows an asynchronous communication design. This means blocking of the user interface or for the loading or storing of data cannot occur anymore. That is already quite a lot. As I understand this, the access to the PIM data will be easier, faster and more efficient. How will this affect the normal user? The possibility for multiple applications to access the same resource existed already in KDE3. As an example, Kopete and Konversation can synchronise contacts. What is the difference to this?

Tobias König: The user will benefit from Akonadi due to the avoidance of inconsistencies between the different presentations of the data in the different applications of the desktop. If a contact in the address book is changed, it automatically updates the birthdays in Plasmoid. The memory usage decreases since the data is only held once in memory.

It will also be possible to integrate PIM data into other KDE applications in a better way. In addition to a users name, his image could be shown in the properties dialogue for a file. The components that communicate the data between the Akonadi server and the data source (i.e. a groupware server) are distributed into separate processes. This protects the system from a crash of a component due to bugs in badly developed software. The crashed component can just be restarted and the data will be re-loaded.. This smells a lot like innovation! Will Akonadi also obtain new or better resource types?

Tobias König: The main task will be to port the existing resource type into Akonadi. The clean and asynchronous interfaces shall increase the liability of the resources. At the moment, there is work on a resource allowing access to MS Exchange. The developer or the alternative KDE email client Mailody also develops a resource, which will allow direct access to IMAP. This means that the KDE client for the Kolab groupware server is not dependent on KMail any more, but Akonadi can communicate directly with the Kolab server. Will this be implemented in KDE 4.1?

Tobias König: KDE 4.1 will include Akonadi as a developer platform. This means that the APIs will be stable and the service is usable. However, not all PIM clients will use Akonadi yet due to missing developer resources. Will KDE4-PIM be based from the beginning on Akonadi?

Tobias König: Yes, but we have also planned for a migration path that will allow to integrate the old resource framework into Akonadi, or allow Akonadi to access the old resources framework. How can someone get involved into the Akonadi development?

Tobias König: One can just contact the KDE PIM developers via the email address, or via the #kontakt channel. Especially the porting of a couple of resources for the Akonadi API should be an easy entry into the world of Akonadi. The development of Akonadi has been for some time ... mmmh ... slow. What have you planned in the next time to make up for the lost time?

Tobias König: The slow progress in the development is merely caused by the lack of developers. At the moment, the main development tasks are performed by 3-4 developers (I want to point out in particular the efforts of Volker Krause. Without him the project would probably already be suspended). Two of them work full time, the other two study or write their thesis. This means that only the evenings or developer meetings are available for the hacking. Apropos developer meetings: During the Easter weekend, there will be a Akonadi hacking meeting in the KDAB offices in Berlin. There, we will double check and improve the API once more. In April will be the API freeze. Hopefully, we will find some time to also implement some of the missing features (maybe we will even hide some Easter eggs :)). This sounds very exiting and innovative. Kubuntu-users are especially interested in the following: Which distribution do you use?

Tobias König: Debian unstable ;). This has historical reasons. At the time when I set up my systems, Ubuntu did not exist yet. Since then, it was not necessary for me to re-install my systems :). Do you already use KDE4 for your daily work? If so, how satisfied are you so far?

Tobias König: Yes, I already use KDE4 for about 3 months. At the beginning, it was irritating that the Plasma desktop had problems every two days. However, it is stable now, and it is possible to work on it. Is there anything else you want to communicate to the world?

Tobias König: Akonadi rocks! :) Thank you for this window into the development of Akonadi. We are exited about the innovations! Thanks for the interview!

Tobias König: You are welcome. It was a pleasure! :)