Comments

Josh Berkus: PostBooks is the pure-OSS GL module from xTuple, which was renamed from OpenMFG. It is an ERP system, very strongly aimed at manufacturers, so would require some substantial adaptation to NPOs. However, it benefits from a strong API in the form of PostgreSQL stored procedures, which would make adapting the basic GL functionality to a more complex NPO module feasible, since interaction with the PostBooks GUI would not be required. One possibility would be to use PostBooks as the backend for a system which also supported ledger-cli; that way users could have the choice of SQL or Git backend.

Daniel Pocock:

I've recently packaged it for Debian and Ubuntu, this may help it achieve wider usage than some of the more heavy weight Java-based ERP solutions as they are not easily packaged
Backend is exclusively PostgreSQL for now
No server processes required other than PostgreSQL itself
Front end is C++ Qt client that each user installs,
it seems to run OK over VPN (IPsec) to a remote PostgreSQL
It has a permissioning system, the PostgreSQL users are Postbooks users
it can be customised by adding fields and buttons to forms and adding custom logic using JavaScript
The developers are also making a full web/mobile Postbooks solution that works with the same database, it is not packaged yet
the developers (xTuple) operate as a software development company maintaining the code, running an annual conference, supporting business deployments, etc
the CPAL license is potentially not GPL compatible, although it is agreed that CPAL is a free license