The NSIS license and the plugin architecture

Hello everyone,

I have used NSIS to create an installer for a proprietary application. I have used the nsDialogs module for a custom wizard page. It works very nicely. However, I have spotted a potential license issue.

NSIS has a liberal open source license that is based on zlib/png. The NSIS license says:

Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions [snip]

which superficially makes it looks like it is ok to use NSIS to create an installer for a proprietary application. After all, it's not as if I am distributing NSIS itself, right? Wrong. When one uses the plugin components then the self-extracting archive that gets created includes DLLs that are part of the installer. So I found that my installer contains nsDialogs.dll. Therefore when I supply my installer I am distributing at least a part of NSIS. My question is, does the license let me do this? The zlib/png license is very short and simple and this seems to be silent on this matter.

Regards,

Andrew Marlow.
http://www.andrewpetermarlow.co.uk

The NSIS installer is of course created by the NSIS compiler so our installer uses the same components as any other installer you might build. All plug-ins exist for use in installers. The compiler does not use them, it just knows how to package them into the installer binary.