Interview with Skype developer Jaanus Kase

When will version 1.0 for Linux arrive?

The version 1.0 release that was launched on July 27 was for the Windows platform, as well as the SkypeOut service. The Linux version 1.0 is on its way and new versions are coming out for closed testing all the time and will reach the public once they're ready. There will not be a significant leap in features between before-1.0 and post-1.0 versions - it's a gradual evolution as we continuously innovate and improve the software.

The Linux client doesn't seem to have the full functionality of the Windows version. In particular, it lacks the advanced settings tab, which limits Skype to the default sound device and makes using a headset difficult. Are there plans to more fully develop the Linux client?

Skype in action

Yes there are plans and in fact, the sound device selection will be available to the public soon. The goal for the Linux version is to bring it on par with the Windows version feature- and quality-wise.

The Skype website does mention the amount of downloads but how many people do you think are using Skype?

Today we know have just over 8 million registered users on Skype as we also track this information. The concurrent online users figure, which you can see in the Skype client, is approaching half a million. These are very significant numbers and they are growing all the time.

How does Skype compete with for example MSN which has the largest share of the instant messaging market?

Skype offers free superior sound quality Internet telephony. In addition, it includes:

In comparison with other IM/voice clients, we can ensure:

We are working on adding more user requested features to the software, such as video calling, etc.

Are there any plans to allow the Skype client to connect to other networks, e.g. MSN, ICQ, Yahoo!, Jabber! etc., like many Linux IM clients?

We believe in interoperability. However, our main goal is to respond to our users' requests and needs, and to focus on continuing to innovate and make Skype the best offering for Internet telephony. Connecting to other networks is currently not a user requested feature for us to make it a priority at the moment.

How many people are working fulltime on Skype?

We have approximately 45 people working on Skype.

Why did you consider writing software for Linux?

Skype for Linux was one of the most requested developments from our user base, but also because we see Linux as an important emerging PC desktop platform. This is illustrated by the fact that many major vendors are starting to offer Linux systems (HP, Sun, IBM to name just a few), and that many companies, government institutions and local governments in Europe, Asia and elsewhere have announced their migration to Linux. The proportion of Skype for Linux users is still small as compared to those running it on Windows, but we expect it to increase over the coming years.

Simply put, we want everyone to be able to run Skype and talk to their friends, family and colleagues, regardless of what platform they use or whether they have a computer at all. Embedded and mobile devices, some of them on Embedded Linux, are an important future development path for Skype.

Skype is released under a proprietary license. It was mentioned in the forums that you may be experimenting with an open source API. Can you tell us a little more about that?

The API is going to be available to other apps over a remote call protocol when the Skype client is running. Other apps can then call Skype functions such as "call this contact", "send IM to this contact" and Skype also notifies other apps about incoming calls, IM-s and other events. A simple usage scenario would be to have a Skype Name field in address book applications and a button for calling those persons. If you then click it, a Skype call is placed.

You invite people to contribute translations for Skype via the forum, which then become the property of Skype. Have you considered a more open community approach, such as that used by the KDE Project?

We see the forum as an open community and we encourage it very much - people upload translations, other people can immediately download and modify them. In general, we try to maintain a friendly relation with various Linux communities including KDE, and some Skype for Linux developers also contribute to KDE apps as their hobby projects.

Are any of those hobby contributions related to Skype in any way?

Currently no.

call list
call list

Have you considered contributing to Qt or any other Free Software projects as part of Skype's development?

We might do that if we get results in our work that would be of value to the community as well as OK to publish according to our license and IP protection policy. However, currently Skype is UI-wise not a very complex project and most of the development effort goes into the proprietary P2P and voice engine that are proprietary code. However, there are some interesting utilities we have done, for example for reusing the same language files and translations in Windows and Linux versions, that we will make available to our users.

If an open source Skype client (not necessarily your one) could be released as part of KDE, you would have your product shipped in almost every Linux distribution, and localised by KDE translators. Would that not outweigh the financial benefits of your closed source model?

Short answer: no. Getting shipped in any Linux distribution is still a small percentage of users, as compared to Windows users. However, having said that, we keep a close eye on the Linux community and its various business models. We are truly multiplatform, already having Windows including Pocket PC, now Linux and upcoming Mac, and we learn from all the users and business models of all the platforms and try to pick the best experiences from each.

Skype currently uses Qt for the Linux GUI. Have you considered using Qt for all three clients, and possibly integrating Skype for Linux with the KDE libraries?

We have considered it, but currently we stay with the native toolkits for each platform - those that our team members have most experience with. However, the world is changing constantly and we cannot say with certainty what UI toolkits we will be using in the next year or five years. We will always be using the toolkit that is the most efficient for us to work with and provides the best user experience.

Skype for Linux will not be closely integrated with KDE libraries, at least not the core part of it. While there might be add-ons, developed by either Skype or the users that have KDE-specific functions, we already have users who work with Skype for Linux on many different window managers and desktop environments, and therefore we want to stay quite desktop-independent.