An API to store balances and transactions

In plain words

Decimals is an API for storing balances and transactions in a ledger system designed for financial applications. Built by Rob, it provides a foundation for tracking money movements with accuracy and security inspired by designs from companies like Square and Uber. The tool emphasizes both scalability and ease of use, drawing on concepts from Ledger CLI to make implementation straightforward for developers building financial systems.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

Hey everyone! I'm Rob and I want to share what I've built - a solid ledger behind simple API: https://decimals.app The ledger is a key piece of any financial system and is easy to get the design wrong, resulting in troubles for making sure money movements are adding up. I took a lot of inspiration from good…

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