The OpenSMTPD project is developed by volunteers and is not backed up by a commercial entity.
As a general rule, you can help the project by donating to the OpenBSD foundation whose goal is to fund OpenBSD and related projects, including LibreSSL upon which we rely. The donations make the OpenBSD infrastructure better and lets OpenBSD organize hackathons where we tend to do a LOT more work than usual.
Alternatively, if you wish to make a donation to the OpenSMTPD project itself, you can use use the button below or send a paypal to firstname.lastname@example.org.
Edward Rosenberg - Zhu Ting - Nathaniel Tammer - High5! - Martin Gauthier - Daniel Pajonzeck - Enric Caussa Morales
Gareth Llewellyn - Benjamin Villain - Thomas Citharel - Pontus Lundkivst - Laurent Theou - Maarten de Vries - Mischa Peters - Renaud Allard - Enric Caussa Morales - Don Harper - Daniel Pajonzeck - Guillaume Vincent - Jason Donenfeld - Ben Perrault - Edward Rosenberg - Antoine Millet - Michael Warmuth-Uhl - Majid Al Suwaidi - Rob Pierce - Martin de Wendt - Erik Harmon