Wagn is licensed under the GNU General Public License (version 2 or later).
"Free" means you're not trapped. You're not trapped paying the licensers every time you want a change. You're not trapped by the whims of the licenser's hosting and pricing policies. You're free. Also, you don't have to pay.
"Open-source" has become a transparency slogan, but it has a specific meaning with software. The "source" is the code that humans can read. If you buy "closed-source" software, you can't see anything readable, so you never really know how it works. That means technical users can't fully customize and improve it. We're proud of our code; we want people to see it, and we thank the many generous developers who help make Wagn better.