Merklized Abstract Syntax Trees (MAST) are a proposed addition to Bitcoin that allows for smaller transaction sizes, more privacy, and larger smart contracts. In this post, we’ll explore the basics of MAST, describe its potential benefits, and summarize some of the current proposals to add it to the Bitcoin Protocol.

The problem: unused script data

Satoshi Nakamoto gave Bitcoin an interesting feature that wasn’t described in the original whitepaper. Instead of requiring bitcoins be received to a public key and spent by a digital signature, Nakamoto gave users the ability to write programs (called scripts) that would act as dynamic public keys and signatures.


What if I told you that there’s a way you can save more than 80% on transaction fees by compressing your Bitcoin transactions? You’d probably think I was crazy or was proposing a radical change to the Bitcoin system. But I’m not.

Since the earliest version of Bitcoin, it has been possible to combine multiple Bitcoin payments into a single transaction, significantly reducing overhead. In this article, we’ll describe why payment batching works, how much it can save you, how to use it, and how much block chain space would be saved if it was used more frequently.

Inputs, change outputs, and payment outputs

Let’s imagine…

David A. Harding

Author of various Bitcoin documentation. My opinions are my own.

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