Amatino is trying to sit at a lower-level of the value chain than reporting, GUIs, and other layers. Amatino aims to enable others to create amazing reporting and GUIs, while charging them an extremely low price to do so.
For ledger entries, create a table and SQL makes a reasonable api. Maybe some stored procedures for protecting integrity.
In my opinion, ledger entries are the hardest part of accounting. Invoices, etc, are all supersets of double-entry accounting, and can be reduced to collections of entries if the underlying double-entry system is sufficiently robust, generic, and and capable.
Such a system should be able to, for example, recursively sum entire account trees, while transparently translating (instantly) across heterogeneous units of account (e.g. stocks, currencies, cryptos, intangibles), and do all that on any device, on any platform, at any time, anywhere on Earth, on demand.
I know this sounds crazy - Sometimes I think I am crazy! Across the world, between companies, and even within Big4 accounting firms, there are infinite ways of constructing an 'invoice' or a 'credit note'. Everyone has their preferred way, none being right or wrong.
Amatino aims to sit below that level - Allowing developers to create their accounting system their way. No compromises.
Again, I really appreciate you looking, even if you think Amatino isn't a worthwhile project. Pondering this reply was in itself a very valuable exercise for me, so thank you for taking the time to comment!