The future of Windows 64-bit builds for KSP

Hi all,

As many of you will most definitely know, Kerbal Space Program has a Windows 64-bit version available to players. We’ve offered this version for a number of past releases of KSP and as of late (0.25 and 0.90, in particular), it has become very apparent that this version has been consistently less stable than all others. This level of instability means that the Windows 64-bit build falls far short of what we would consider a release-worthy product, and we will therefore not be releasing it for version 1.0 of Kerbal Space Program*.

We’ve spent a considerable amount of time investigating the reasons for these issues. The QA & Experimental Testing Teams have assisted in this research as have the community - something that we are very grateful for.

However, despite these efforts and although we have identified a number of probable causes for the instability, there is a very hard limit on what can be done on our end. Most platform-specific issues stem from parts of the engine we have no direct access to, and we simply can’t debug these problems in the same way we’d do with normal KSP bugs. We often can’t even reproduce them in our development environment, so we’re limited to guessing at both the causes and solutions.

In short, there are no easy fixes we can do here, and we feel that the time we would be potentially wasting on attempting to increase the stability of the Windows 64-bit version of KSP would be far better spent on other improvements which would reach as many players as possible. We can all agree there is no shortage of other things we could be working on.

We’re not giving up on the 64-bit build for Windows, though. The most we can do at the moment, however, is continue testing the Windows 64-bit build at each new version of Unity, and release it if viable. Additionally, we must take this opportunity to stress that Unity 5 - while a definite leap in the capabilities, performance and development power of the engine - is not going to inherently be a ‘cure all’ for issues, particularly in the matter of the instability of the Windows 64-bit build.

We’re aware that some of you have come to embrace the Windows 64 bit version by this point and that our decision to discontinue development for this particular build may be an inconvenience to some, but we trust everyone will understand the necessity that prompted this decision. At any rate, we want to thank everyone for their efforts in assisting in all bug finding and bug fixing efforts for KSP, as well as the modding community for their efforts in dealing with a rather unstable platform.

We hope you’re all looking forward to 1.0! We’ll be sharing more news with you as development continues.

*Note that this doesn't affect those that run KSP on 64-bit versions of Windows, only those that run the 64-bit Windows version of KSP. Additionally, the 64-bit build for Linux is still planned to be released for 1.0.