Ok the bdk looks like a far better bet!

side-node/Cargo.toml

@@ -6,7 +6,11 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+anyhow = "1.0.86"
 async-trait = "0.1.52"
+bdk = "0.29.0"
+bdk_esplora = "0.15.0"
+bdk_sqlite = "0.2.0"
 bdk_wallet = { version = "1.0.0-alpha.13", features = ["all-keys"] }
 bft-json-crdt = { path = "../crates/bft-json-crdt" }
 bft-crdt-derive = { path = "../crates/bft-json-crdt/bft-crdt-derive" }
@@ -15,15 +19,16 @@ clap = { version = "4.5.4", features = ["derive"] }
 dirs = "5.0.1"
 ezsockets = { version = "*", features = ["client"] }
 fastcrypto = "0.1.8"
+indexmap = { version = "2.2.6", features = ["serde"] }
 # serde_cbor = "0.11.2" # move to this once we need to pack things in CBOR
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0.117"
 sha256 = "1.5.0"
 tokio = { version = "1.37.0", features = ["full"] }
+toml = "0.8.14"
 tracing = "0.1.32"
 # tracing-subscriber = "0.3.9"
-toml = "0.8.14"
-indexmap = { version = "2.2.6", features = ["serde"] }
+
 
 [dev-dependencies]
 uuid = { version = "1.8.0", features = ["v4"] }

side-node/src/clients/btc_rpc.rs

@@ -1,3 +1,114 @@
-pub fn run(name: &str) {
-    println!("running btc_rpc...");
+use std::{collections::BTreeSet, io::Write, str::FromStr};
+
+use bdk_esplora::{esplora_client, EsploraAsyncExt};
+use bdk_wallet::{
+    bitcoin::{Address, Amount, Network, Script},
+    KeychainKind, SignOptions, Wallet,
+};
+
+use bdk_sqlite::{rusqlite::Connection, Store};
+
+const SEND_AMOUNT: Amount = Amount::from_sat(5000);
+const STOP_GAP: usize = 50;
+const PARALLEL_REQUESTS: usize = 5;
+
+pub async fn run() -> Result<(), anyhow::Error> {
+    let db_path = "/tmp/bdk-esplora-async-example.sqlite";
+    let conn = Connection::open(db_path)?;
+    let mut db = Store::new(conn)?;
+    let external_descriptor = "wpkh(tprv8ZgxMBicQKsPdy6LMhUtFHAgpocR8GC6QmwMSFpZs7h6Eziw3SpThFfczTDh5rW2krkqffa11UpX3XkeTTB2FvzZKWXqPY54Y6Rq4AQ5R8L/84'/1'/0'/0/*)";
+    let internal_descriptor = "wpkh(tprv8ZgxMBicQKsPdy6LMhUtFHAgpocR8GC6QmwMSFpZs7h6Eziw3SpThFfczTDh5rW2krkqffa11UpX3XkeTTB2FvzZKWXqPY54Y6Rq4AQ5R8L/84'/1'/0'/1/*)";
+    let changeset = db.read()?;
+
+    let mut wallet = Wallet::new_or_load(
+        external_descriptor,
+        internal_descriptor,
+        changeset,
+        Network::Signet,
+    )?;
+
+    let address = wallet.next_unused_address(KeychainKind::External);
+    if let Some(changeset) = wallet.take_staged() {
+        db.write(&changeset)?;
+    }
+    println!("Generated Address: {}", address);
+
+    let balance = wallet.balance();
+    println!("Wallet balance before syncing: {} sats", balance.total());
+
+    print!("Syncing...");
+    let client = esplora_client::Builder::new("http://signet.bitcoindevkit.net").build_async()?;
+
+    fn generate_inspect(kind: KeychainKind) -> impl FnMut(u32, &Script) + Send + Sync + 'static {
+        let mut once = Some(());
+        let mut stdout = std::io::stdout();
+        move |spk_i, _| {
+            match once.take() {
+                Some(_) => print!("\nScanning keychain [{:?}]", kind),
+                None => print!(" {:<3}", spk_i),
+            };
+            stdout.flush().expect("must flush");
+        }
+    }
+    let request = wallet
+        .start_full_scan()
+        .inspect_spks_for_all_keychains({
+            let mut once = BTreeSet::<KeychainKind>::new();
+            move |keychain, spk_i, _| {
+                match once.insert(keychain) {
+                    true => print!("\nScanning keychain [{:?}]", keychain),
+                    false => print!(" {:<3}", spk_i),
+                }
+                std::io::stdout().flush().expect("must flush")
+            }
+        })
+        .inspect_spks_for_keychain(
+            KeychainKind::External,
+            generate_inspect(KeychainKind::External),
+        )
+        .inspect_spks_for_keychain(
+            KeychainKind::Internal,
+            generate_inspect(KeychainKind::Internal),
+        );
+
+    let mut update = client
+        .full_scan(request, STOP_GAP, PARALLEL_REQUESTS)
+        .await?;
+    let now = std::time::UNIX_EPOCH.elapsed().unwrap().as_secs();
+    let _ = update.graph_update.update_last_seen_unconfirmed(now);
+
+    wallet.apply_update(update)?;
+    if let Some(changeset) = wallet.take_staged() {
+        db.write(&changeset)?;
+    }
+    println!();
+
+    let balance = wallet.balance();
+    println!("Wallet balance after syncing: {} sats", balance.total());
+
+    if balance.total() < SEND_AMOUNT {
+        println!(
+            "Please send at least {} sats to the receiving address",
+            SEND_AMOUNT
+        );
+        std::process::exit(0);
+    }
+
+    let faucet_address = Address::from_str("mkHS9ne12qx9pS9VojpwU5xtRd4T7X7ZUt")?
+        .require_network(Network::Signet)?;
+
+    let mut tx_builder = wallet.build_tx();
+    tx_builder
+        .add_recipient(faucet_address.script_pubkey(), SEND_AMOUNT)
+        .enable_rbf();
+
+    let mut psbt = tx_builder.finish()?;
+    let finalized = wallet.sign(&mut psbt, SignOptions::default())?;
+    assert!(finalized);
+
+    let tx = psbt.extract_tx()?;
+    client.broadcast(&tx).await?;
+    println!("Tx broadcasted! Txid: {}", tx.compute_txid());
+
+    Ok(())
 }

side-node/src/lib.rs

@@ -31,7 +31,7 @@ pub async fn run() {
             node.start().await;
         }
         Some(Commands::Btc {}) => {
-            clients::btc_rpc::run("sammy_wallet");
+            let _ = clients::btc_rpc::run().await;
         }
         None => println!("No command provided. Exiting. See --help for more information."),
     }

side-node/src/utils.rs

@@ -1,8 +1,6 @@
-use std::path::PathBuf;
-
 use bft_json_crdt::json_crdt::SignedOp;
-use bitcoin::{absolute, key::Keypair, transaction::Version, TxIn, TxOut};
 use serde_json::{json, Value};
+use std::path::PathBuf;
 
 pub(crate) const BITCOIN_KEY_FILE: &str = "bitcoin_keys.pem";
 pub(crate) const BFT_CRDT_KEY_FILE: &str = "keys.pem";
@@ -40,29 +38,29 @@ pub fn fake_generic_transaction_json(from: String) -> Value {
 }
 
 /// Generate a Bitcoin transaction from this node's bitcoin_keys
-pub fn fake_bitcoin_transaction(key_pair: Keypair) -> bitcoin::Transaction {
-    let from = key_pair.public_key().to_string();
-    let to = "Bob";
-    let amount = 1;
-    let lock_time = absolute::LockTime::from_height(0).expect("couldn't format btc lock time");
-    let input = TxIn {
-        previous_output: todo!(),
-        script_sig: todo!(),
-        sequence: todo!(),
-        witness: todo!(),
-    };
-    let output = TxOut {
-        value: todo!(),
-        script_pubkey: todo!(),
-    };
-    let tx = bitcoin::Transaction {
-        version: Version(1),
-        lock_time,
-        input: vec![input],
-        output: vec![output],
-    };
-    tx
-}
+// pub fn fake_bitcoin_transaction(key_pair: Keypair) -> bitcoin::Transaction {
+//     let from = key_pair.public_key().to_string();
+//     let to = "Bob";
+//     let amount = 1;
+//     let lock_time = absolute::LockTime::from_height(0).expect("couldn't format btc lock time");
+//     let input = TxIn {
+//         previous_output: todo!(),
+//         script_sig: todo!(),
+//         sequence: todo!(),
+//         witness: todo!(),
+//     };
+//     let output = TxOut {
+//         value: todo!(),
+//         script_pubkey: todo!(),
+//     };
+//     let tx = bitcoin::Transaction {
+//         version: Version(1),
+//         lock_time,
+//         input: vec![input],
+//         output: vec![output],
+//     };
+//     tx
+// }
 
 pub fn shappy(op: SignedOp) -> String {
     let b = serde_json::to_string(&op).unwrap().into_bytes();