A few years ago I began writing a software package to generate characters for the HackMaster RPG called HMTK or "Steve's No Frills HackMaster Toolkit."

Lately I have been considering publishing the source code and letting others develop the software further. I have one problem, with so many potential licenses out there, which one should I use?

The granddaddy of them all has to be the BSD License.

The BSD License is known for being the most permissive of all software licenses without entering the public domain.

The only restriction the BSD license imposes is that you have to tell people you included the code and that it is not yours. Otherwise you are free to do whatever you want with it!

Clearly, this is far to open of a license for me to use.

Next up we have the juggernaut of the free software world... GPL!

The GPL is often characterized as being "viral" in nature. Well, yes, it can "infect" a software project, but only if YOU actively infect yourself! If you want to keep the viral GPL out of your software then don't steal GPL code! It's as easy as that.

The GPL is no more viral than a criminal record. If you do not commit crimes then you will not have a criminal record. If you DO commit crimes then you WILL have a criminal record.

The GPL would allow me to retain control of my source code and distribute it. It would also allow the people who use my code to modify it. However, if they modify it and redistribute it ten the modified work must also be distributed under the same conditions they received the code from me under.

It's not too bad and the GPL is designed to foster sharing of software and sharing of modifications.

The GPL also protects me against a user taking my code and making a proprietary software package from it.

At the same time, once one person gets my code base they can redistribute it at no charge. That would kill any potential revenue stream...

Lastly I will look at the Creative Commons License Project.

Creative Commons is a very interesting project in that it is akin to a license with plug-ins.

You start with your copyright and then you can mix and match various restrictions until you get what you want.

For example, the content on this blog is licensed under a "Attribution Non-commercial No Derivatives (by-nc-nd)" license that says:

This license is the most restrictive of our six main licenses, allowing redistribution. This license is often called the "free advertising" license because it allows others to download your works and share them with others as long as they mention you and link back to you, but they can't change them in any way or use them commercially.

This works well enough for my blog content, but what about software?

My main goal with the software is to allow others to modify the code and send me changes to incorporate into the program. I'd like to be able to still make some money off of the software (even programmers need to eat) and I do not want someone to steal my code and use it for their profit.

Looking over the Creative Commons License choices I don't see one that fits my needs for this project.

Do you know of a software license I should consider?

I'd like to go to a donation supported system for this and allow others to modify the code. I could go to a hybrid donation/ransom system where upon reaching a certain donation threshold the licensing on the source code becomes far less restrictive.

Right now I'm stuck. I don't have the free time to give the software the attention it needs and I can't afford to just give it away. So, what should I do?