Moonpig: a billing system that doesn't suck

TigerBeetle

The financial transactions database designed for mission critical safety and performance.

Django Hordak

Core functionality of a double entry accounting system for Django

Books, an immutable double-entry accounting database service

Explain the basic data model of a double-entry accounting system relying on Google Spanner for internal use at Square

Triple‐entry accounting with Blockchain: How far have we come?

“Triple‐entry accounting is a new and a more efficient way to address fundamental trust and transparency issues that plague current accounting systems. Triple‐entry accounting with Blockchain, when properly implemented, can fundamentally improve accounting.”