Install Bitcoin Core and start it

After this lesson you can: run the reference software on your own machine and know that the copy you are running is the one the developers signed.

Which path

This lesson is the "Bitcoin Core directly" path from the previous lesson. If you chose a turnkey bundle (Umbrel, Start9), it does these steps for you behind a dashboard; the video at the end shows that route. Either way the software underneath is the same.

Steps

1. 01Go to bitcoincore.org/en/download and download the build for your operating system, plus SHA256SUMS and SHA256SUMS.asc.
2. 02Verify. Compute the file's SHA-256 and find it in SHA256SUMS; then check the signatures on SHA256SUMS.asc with the developers' keys listed on the download page (several developers sign each release; any "Good signature" from a key you fetched independently is enough). The Self-custody course's verification lesson has the commands.
3. 03Install. On a desktop you get Bitcoin-Qt, the graphical node and wallet. On a server, bitcoind plus bitcoin-cli.
4. 04On first run, choose the data directory. This is where the chain will live: point it at your SSD. Decide full or pruned: pruned keeps a few gigabytes of recent blocks and still verifies everything; full keeps the whole chain and can serve it to others.
5. 05Optional: write a minimal bitcoin.conf in the data directory, for example prune=20000 (keep about 20 GB) or txindex=1 (full node only; needed by some explorers). Leave the RPC port local.
6. 06Start it. The window or bitcoin-cli getblockchaininfo shows headers arriving, then blocks. Leave it running; the next lesson explains what the sync is doing and how long it takes.
7. 07Disable the built-in wallet if you will not use it (disablewallet=1), so the node is just a node.

Check your work

bitcoin-cli getnetworkinfo shows the version you installed; it should match the release you verified. getblockchaininfo shows pruned: true or false as you intended and a rising blocks count.