[passenger]

I've been along these lines in the past few weeks as well.

Some examples I've come across https://github.com/snipe/snipe-it Uses GNU Affero General Public License v3.0[]

Invoice Ninja (https://github.com/invoiceninja/invoiceninja/) uses an ATTRIBUTION ASSURANCE LICENSE (adapted from the original BSD license).

I hope these can guide you in the right direction