Crate bitcoind

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MIT license Crates Docs


Utility to run a regtest bitcoind process, useful in integration testing environment.

When the auto-download feature is selected by activating one of the version feature, such as 23_1 for bitcoin core 23.1, starting a regtest node is as simple as that:

// the download feature is enabled whenever a specific version is enabled, for example `23_1` or `22_1`
#[cfg(feature = "download")]
  use bitcoincore_rpc::RpcApi;
  let bitcoind = bitcoind::BitcoinD::from_downloaded().unwrap();
  assert_eq!(0, bitcoind.client.get_blockchain_info().unwrap().blocks);

The build script will automatically download the bitcoin core version 23.1 from bitcoin core, verify the hashes and place it in the build directory for this crate. If you wish to download from an alternate location, for example locally for CI, use the BITCOIND_DOWNLOAD_ENDPOINT env var.

When you don’t use the auto-download feature you have the following options:

  • have bitcoind executable in the PATH
  • provide the bitcoind executable via the BITCOIND_EXEC env var
use bitcoincore_rpc::RpcApi;
if let Ok(exe_path) = bitcoind::exe_path() {
  let bitcoind = bitcoind::BitcoinD::new(exe_path).unwrap();
  assert_eq!(0, bitcoind.client.get_blockchain_info().unwrap().blocks);

Startup options could be configured via the Conf struct using BitcoinD::with_conf or BitcoinD::from_downloaded_with_conf

Issues with traditional approach

I used integration testing based on external bash script launching needed external processes, there are many issues with this approach like:

  • External script may interfere with local development environment 1
  • Use of a single huge test to test everything 2
  • If test are separated, a failing test may fail to leave a clean situation, causing other test to fail (because of the initial situation, not a real failure)
  • bash script are hard, especially support different OS and versions


  • It waits until bitcoind daemon become ready to accept RPC commands
  • bitcoind use a temporary directory as datadir. You can specify the root of your temp directories so that you have node’s datadir in a RAM disk (eg /dev/shm)
  • Free ports are asked to the OS. Since you can’t reserve the given portm a low probability race condition is still possible, for this reason the process is tried to be spawn 3 times with different ports.
  • The process is killed when the struct goes out of scope no matter how the test finishes
  • Allows easy spawning of dependent process like electrs

Thanks to these features every #[test] could easily run isolated with its own environment.


To build docs:

RUSTDOCFLAGS="--cfg docsrs" cargo +nightly doc --features download,doc --open


The MSRV is 1.41.1 for version 0.29.* if no feature is used, otherwise is 1.57

Note: to respect 1.41.1 MSRV you need to use and older version of the which and tempfile dependencies, like it’s done in the CI:

cargo update -p which --precise 4.3.0
cargo update -p serde --precise 1.0.152
cargo update -p tempfile --precise 3.3.0

Pinning in Cargo.toml is avoided because it could cause compilation issues downstream.


For reproducibility reasons, Nix build scripts cannot hit the internet, but the auto-download feature does exactly that. To successfully build under Nix the user must provide the tarball locally and specify its location via the BITCOIND_TARBALL_FILE env var.

Used by

Via bdk dependency

Via electrsd dependency:



  • Struct representing the bitcoind process with related information
  • The node configuration parameters, implements a convenient Default for most common use.
  • Contains all the information to connect to this node


  • The DataDir struct defining the kind of data directory the node will contain. Data directory can be either persistent, or temporary.
  • All the possible error in this crate
  • Enum to specify p2p settings


  • Provide the bitcoind executable path if a version feature has been specified
  • Returns the daemon bitcoind executable with the following precedence:
  • Returns a non-used local port if available.
  • Validate the specified arg if there is any unavailable or deprecated one