WHMCS - WHMCS is an all-in-one client management, billing & support system for online businesses.
ARGONAUT - Definition, Synonyms, Translations of Argonaut by The Free Dictionary
HostBill - HostBill is a powerful and flexible, all-in-one automation, billing, client management and support platform for online businesses.
Digger - Build on AWS without having to learn it, no-code DevOps
Blesta - Blesta is professional client management, billing, and support software.
Dealflow by Micro Acquisitions - Automate your small business acquisition pipeline