Is it possible to use third-party libs under the GPL3 license?

Question

.NET

The bottom line is that the app is written in .net under the GNU General Public License v3.0
How do I choose third-party libs? Can I use closed source libs?

Answer 1

In a nutshell, the GPL is a "viral" license, so linking GPL code to any code turns out to be GPL too.
If the final code is not GPL, this is a violation.
If either has a license that does not allow it to be published under the GPL, then you cannot link it to the GPL code.
I advise you not to read the retellings of the license, but to study one of the translations or at least an article on the wiki.