Donations for open source projects have notoriously low participation rates - to the point where popular and critical infrastructure projects can't afford to maintain a fulltime employee or two - so don't take it personally.

If you want companies to pay you, then ask them to pay you. Keep it as a simple license (not one that has devs asking wtf it is), but offer a commercial bundle with email and dev support, LTS, backwards compat and perhaps authentication modules (for LDAP/AD, OAuth) and I think you'd be surprised by just how many companies make these purchases (I make them all the time).

Also, on price - $100-300 is "no-brainer i'll put it on my credit card and expense it at the end of the month" while €800 is approaching purchasing decision territory for a lot of companies.

Smart guy. Copyleft for the open source crowd to use freely, commercial license for businesses who want to keep their own source closed.

I wonder where you get a good commercial license to use like this. Is it always a custom thing requiring expensive lawyers or is there some repo of commercial licenses one can use?

It's a great piece of software. I use it in two projects both commercial platforms though not particularly big money makers.

The problem for me is I remain somewhat uncertain about the implications. If I use this within a service that requires payment from customers, it seems to me there is no change. And most software using this is likely to be delivered as a service right? Maybe I misunderstand the license.

In a way if the approach was more aggressive it would be easier for me. I could just go to the people that write the cheques and say: we use this software. New version requires payment. Write a cheque.

As it is I'm not sure whether we have to pay or not. As for donations - well I could make one personally (in fact I will) but it is unlikely to be 780 euros...

I understand the switch to copyleft, but the EU's own website explicitly lists GPL licenses as incompatible, in the matrix on this page:

https://joinup.ec.europa.eu/software/page/eupl/eupl-compatib...

Dual-licensing under the EUPL and GPL, with the option to choose either, would be helpful. Otherwise Nodemailer is incompatible with the majority of other copyleft code.

Hmm. A wee bit off-topic, but is there a license of these sorts that do the "free until you make X revenue", similar to those used by Unreal and Unity?

andris9, you mentioned that the EUPL was more European Union friendly, similar to how GPL is more USA friendly.

Do you mind elaborating what you mean by this?

Spoiler: Money.