Electrum Personal Server

Electrum Personal Server is an implementation of the Electrum server protocol which fulfills the specific need of using the Electrum UI with full node verification and privacy, but without the heavyweight server backend, for a single user. It allows the user to benefit from all of Bitcoin Core's resource-saving features like pruning, blocksonly and disabled txindex. All of Electrum's feature-richness like hardware wallet integration, multisignature wallets, offline signing, mnemonic recovery phrases and so on can still be used, but backed by the user's own full node.

Using Electrum with Electrum Personal Server is probably the most resource-efficient way right now to use a hardware wallet connected to your own full node.

For a longer explaination of this project and why it's important, see the mailing list email and bitcointalk thread.

See also the Electrum bitcoin wallet website.

How To Use

This application requires python3 and a Bitcoin full node built with wallet capability.

Download the latest release or clone the git repository. Enter the directory and rename the file config.cfg_sample to config.cfg, edit this file to configure your bitcoin node json-rpc authentication details. Next add your wallet addresses to the [wallets] section.

Finally run ./server.py on Linux or double-click run-server.bat on Windows. The first time the server is run it will import all configured addresses as watch-only into the Bitcoin node, and then exit giving you a chance to -rescan if your wallet contains historical transactions.

Electrum wallet must be configured to connect to the server. SSL must be disabled which can be done either by Tools -> Connection -> Uncheck box Use SSL, or starting with the command line flag --nossl, depending on the version of Electrum. Tell Electrum to connect to the server in Tools -> Server, usually localhost if running on the same machine.

Note that you can also try this with on testnet bitcoin. Electrum can be started in testnet mode with the command line flag --testnet.

Exposure to the Internet

You really don't want other people connecting to your server. They won't be able to synchronize their wallet, and they could potentially learn all your wallet addresses.

By default the server will bind to and accept connections only from localhost so you should either run Electrum wallet from the same computer or use a SSH tunnel.

Project Readiness

This project is in alpha stages as there are several essential missing features such as:

• Merkle proofs are not handled, so every confirmed transaction is labelled Not Verified.

• The server does not support SSL so Electrum must be configured to disable it.

• Deterministic wallets and master public keys are not supported. Addresses must be imported individually.

• Bech32 bitcoin addresses are not supported.

• The Electrum server protocol has a caveat about multiple transactions included in the same block. So there may be weird behaviour if that happens.

• There's no way to turn off debug messages, so the console will be spammed by them when used.

When trying this, make sure you report any crashes, odd behaviour or times when Electrum disconnects (which indicates the server behaved unexpectedly).

Someone should try running this on a Raspberry PI.

Contributing

I welcome contributions. Please keep lines under 80 characters in length and ideally don't add any external dependencies to keep this as easy to install as possible.

I can be contacted on freenode IRC on the #bitcoin and #electrum channels.