Run Your Own Play-Money Server

1. Basics

• Spin up a new server (such as linode), with Ubuntu 24 (or whatever you prefer).

• To it, add:

• • Bitcoin Core (patched)
• • The Bip300 Enforcer

Create bitcoin.conf (at /.bitcoin/bitcoin.conf) , and make sure it contains:

rpcuser=user
rpcpassword=password
txindex=1
server=1
zmqpubsequence=tcp://0.0.0.0:29000
  # required to interact with the enforcer   
signet=1
signetblocktime=60
  # 1 minute block times. Note that /everyone/ who connects to this signet
  # must have this exact configuration value.

Step 2 (below) will add the signetchallenge=... line.

2. Create a Mining Key

This key will sign a new block into existence, every 60 seconds.

Note: This is using Fish shell, if you are using Bash or Zsh then ask an AI for help.

$ mkdir l2l-signet
$ ./build/src/bitcoind -daemon -regtest -datadir=$PWD/l2l-signet

$ ./build/src/bitcoin-cli -regtest -datadir=$PWD/l2l-signet \
     createwallet l2l-signet

$ set signet_challenge (./build/src/bitcoin-cli -regtest -datadir=$PWD/l2l-signet \
                     getaddressinfo $address | jq -r .scriptPubKey)

$ echo signetchallenge=$signet_challenge >> l2l-signet/bitcoin.conf

# Need the wallet descriptors to be able to import the wallet into
$ set descriptors (./build/src/bitcoin-cli -regtest -datadir=$PWD/l2l-signet \
                     listdescriptors true | jq -r .descriptors)

# We're finished with the regtest wallet!
$ ./build/src/bitcoin-cli -regtest -datadir=$PWD/l2l-signet stop

3. Create the signet wallet

$ ./build/src/bitcoind -daemon -signet -datadir=$PWD/l2l-signet

$ ./build/src/bitcoin-cli -signet -datadir=$PWD/l2l-signet \
     createwallet l2l-signet

$ ./build/src/bitcoin-cli -signet -datadir=$PWD/l2l-signet \
    importdescriptors "$descriptors"

4. Start mining

This will run the 'generate' command, creating a new block on your network every 60 seconds.

$ set address (./build/src/bitcoin-cli -signet -datadir=$PWD/l2l-signet getnewaddress)

$ ./contrib/signet/miner \
    --cli "bitcoin-cli -signet -datadir=$PWD/l2l-signet" \
    generate --address $address \
    --grind-cmd "$PWD/build/src/bitcoin-util grind" \
    --min-nbits --ongoing --block-interval 60

You now have your own play money server.

5. Give This Info To Your Friends

Those joining the network (ie, non-mining nodes) must have the same bitcoin.conf , plus an "addnode" line.

The addnode line is your server's IP address + port 8332 . For us at L2L, this is 172.105.148.135:8332 :

rpcuser=user
rpcpassword=password
server=1
txindex=1
signet=1
signetblocktime=60
signetchallenge=00141f61d57873d70d28bd28b3c9f9d6bf818b5a0d6a
zmqpubsequence=tcp://0.0.0.0:29000
addnode=172.105.148.135:8332

But yours will have different values for "addnode", "signetchallenge".

6. Activate a Sidechain

The file mine_signet.sh will attempt to activate the thunder sidechain in slot 1, and mine a few blocks.

7. Checking in on the Mining Server

If the mining server crashes (or stops for any reason), you can examine it by:

• ssh into server
• su [your user name]
• cd into /home/[your user name]
• run ps aux | grep mine_signet to determine if the mining script is running

Then you can restart it by re-running the commands in Step 4.