Tests against open source projects are free and don't count towards your test usage. If your source code is available publicly on the internet, you can mark your project as open source by following these steps.
If you haven’t done so already, run snyk monitor in your terminal to create a project on Snyk
On the Snyk website, view your projects and select the CLI project you just created
Click on “settings” from the right hand side of this page to change the project settings
Enter a git URI to the source code for your project where it says “Git remote URI”. If your code is hosted on GitHub, you can find this by clicking the “Clone or download” button and copying the URI.
If we are able to verify that the URI points to a git repository then your project will be marked as open source and will no longer be tracked against your private project test usage.