We've been building a source/destination ledger at nxos (and I've worked with similar systems in the past). The relationship between debits and credits in such a ledger wasn't always clear to me. However, writing this post did help me to show how these concepts map and how it's fairly straightforward to model accounting standards on such a ledger. While exploring this topic, I also learned significantly more about why debits/credits affect different account types differently and why different account types exist in the first place. I hope you might find it as interesting as I did!