I need a software to create digitally signed deal documents such as invoices and receipts, which is:
- In English
- FOSS (thus communally maintained and supervised - with no customer service)
- Communicates with an email server to send deal documents to customers from the software's own email server
- Allows easy manual backuping of all deal documents already created
I could add that I grasp such software as "apolitical" in the sense that it isn't associated with the taxation authority of any particular state or country; rather, it allows humans anywhere in the world to do global, free and easy bookkeeping.
Which such software will you recommend?
My prior research brought invoiceninja.com but they don't have digital signage service (confirmed with their customer service on 29/06/20).