The pgloader project is fully Open Source and released under The PostgreSQL License so that anyone can easily contribute to the project. The whole project management (issue tracking, feature proposals, etc) happens on the pgloader github page, in public.
Software development may be open, and the result shared with an Open Source Software licence, but the actual hours of programming are not gratis.
Just like everybody else, I need money for mortgage, kids and food, money I make by doing things with computers, for people who are willing to pay for that. One of the things I do for money, is develop pgloader, and the pgloader Moral License is a good vehicle available for the paperwork. I shamelessly stole the whole idea from The Varnish Moral License. See the Varnish Moral License FAQ and How To to see how PHK does it.
Happy pgloader users tell me that they want a pgloader Moral License. I send them an invoice from my company. They pay the invoice, I develop pgloader.
If you or your company prefer more classic paperwork (as known as contracting or sponsoring), of course that is still possible too, just get in touch!