Getting OP_RETURN Bitcoin Messages

This is mainly a note to myself as every time I want to do this I end up searching through my history doing something like this. So here’s the code to extract the OP_RETURN message from the bitcoin blockchain. This needs to be run on the machine running your full node. The output looks like …

Bitcoin Proof of Work

(With try yourself code!) As much as bitcoin (note here I’m talking about the software also known as bitcoin core) is a highly complex system many of the basic elements can be fairly easily described and demonstrated. Here I’ll demonstrate a very simple example using python showing how mining works and how something called ‘difficulty’ …

Piping Bitcoin RPC Commands

If you want to get the block header of the latest block generated on the bitcoin blockchain using bitcoin-cli it’s a little tricky (and hard to say!). You need to first find the latest block number (height), then find the hash of that block and then get the header using the hash. Since the getblockheader …

Bitcoin RPC Commands over SSH Tunnel

If you’re running a Bitcoin full node and want to run RPC commands against the Bitcoin client from a remote machine the easiest and safest way to do this is using Port Forwarding over an SSH connection. What is Port Forwarding used for? Secure access to a port that is otherwise not listening on a …

Setting Up a Local Blockchain with Ganache

Why would I want to do this? Interacting with Blockchains and blockchain technology probably seems for most people like a very complex task. How to even get started? Don’t they run on some servers spread across the globe? How would I make a transaction and see the result? Wouldn’t I use to use real money …

Monitoring a Bitcoin Node Using Node-RED

Now my Bitcoin Full Node is fully synchronized and running I thought it would be good to set up some simple monitoring to check it’s still up and up to date with the Bitcoin Blockchain. Bitnodes API Helpfully there’s already a site that monitors all the full nodes and also provides a handy API at …

Running a Bitcoin Full Node on a Raspberry Pi 4

First Attempt I’ve wanted to run a Bitcoin full node for a while now. Not because it makes any money, quite to the contrary, it actually costs money to run a node, but to better understand a technology there’s nothing better than learning by doing 🧠 A full node is a program that fully validates …