LedgerSMB is a libre software double entry accounting, Invoicing and Enterprise Resource Planning (ERP) system, focussed on functionality required by small (self-employment) and medium size businesses. The development team doesn't shy away for multi-million transaction volumes and deployments with over 3 million journal lines as well as >4k invoices _per week_ are known to exist.

Homepage	https://ledgersmb.org/
Development	https://github.com/ledgersmb/