feat(nwc): add NIP-47 wallet service support

Introduce a transport-agnostic cdk-nwc crate that connects to Nostr
relays, advertises supported NWC commands, validates authorized requests,
deduplicates event ids, and publishes encrypted responses.

Add a CDK wallet handler for get_info, get_balance, make_invoice,
pay_invoice, lookup_invoice, and list_transactions, including msat/unit
conversion, quote lookup, and per-payment limits.

Expose the service through UniFFI and add an example plus an end-to-end
relay-backed NWC flow test.

Author: asmogo

Cargo.lock

@@ -72,6 +72,7 @@ cdk-mintd = { path = "./crates/cdk-mintd", version = "=0.17.0", default-features
 cdk-prometheus = { path = "./crates/cdk-prometheus", version = "=0.17.0", default-features = false }
 cdk-supabase = { path = "./crates/cdk-supabase", version = "=0.17.0", default-features = false }
 cdk-npubcash = { path = "./crates/cdk-npubcash", default-features = false, version = "=0.17.0" }
+cdk-nwc = { path = "./crates/cdk-nwc", version = "=0.17.0" }
 cdk-bdk = { path = "./crates/cdk-bdk", version = "=0.17.0", default-features = false }
 clap = { version = "4.5.31", features = ["derive"] }
 ciborium = { version = "0.2.2", default-features = false, features = ["std"] }
@@ -127,6 +128,7 @@ prometheus = { version = "0.13.4", features = ["process"], default-features = fa
 nostr-sdk = { version = "0.44.1", default-features = false, features = [
     "nip04",
     "nip44",
+    "nip47",
     "nip59"
 ]}
 bitcoin-payment-instructions = { version = "0.7.0", default-features = false }

Cargo.lock.msrv

@@ -17,7 +17,7 @@ name = "uniffi-bindgen"
 path = "uniffi-bindgen.rs"
 
 [dependencies]
-cdk-ffi = { workspace = true, features = ["npubcash", "bip353"] }
+cdk-ffi = { workspace = true, features = ["npubcash", "nwc", "bip353"] }
 uniffi = { workspace = true, features = ["cli"] }
 uniffi-dart = { git = "https://github.com/Uniffi-Dart/uniffi-dart", tag = "v0.1.0+v0.30.0"  }
 camino = "1.2"

Cargo.toml

@@ -13,7 +13,7 @@ crate-type = ["cdylib"]
 name = "cdk_ffi_go"
 
 [dependencies]
-cdk-ffi = { workspace = true, features = ["npubcash", "bip353"] }
+cdk-ffi = { workspace = true, features = ["npubcash", "nwc", "bip353"] }
 uniffi = { workspace = true, features = ["cli"] }
 
 [build-dependencies]

bindings/dart/rust/Cargo.toml

@@ -17,7 +17,7 @@ name = "uniffi-bindgen"
 path = "uniffi-bindgen.rs"
 
 [dependencies]
-cdk-ffi = { workspace = true, default-features = false, features = ["npubcash", "bip353"] }
+cdk-ffi = { workspace = true, default-features = false, features = ["npubcash", "nwc", "bip353"] }
 uniffi = { workspace = true, features = ["cli"] }
 
 [build-dependencies]

bindings/go/rust/Cargo.toml

@@ -18,7 +18,7 @@ name = "uniffi-bindgen-swift"
 path = "uniffi-bindgen-swift.rs"
 
 [dependencies]
-cdk-ffi = { workspace = true, default-features = false, features = ["npubcash", "bip353"] }
+cdk-ffi = { workspace = true, default-features = false, features = ["npubcash", "nwc", "bip353"] }
 uniffi = { workspace = true, features = ["cli"] }
 
 

bindings/kotlin/rust/Cargo.toml

@@ -21,7 +21,9 @@ cdk-sqlite = { workspace = true }
 cdk-postgres = { workspace = true, optional = true }
 cdk-supabase = { workspace = true, optional = true, features = ["wallet"] }
 cdk-npubcash = { workspace = true, optional = true }
+cdk-nwc = { workspace = true, optional = true }
 nostr-sdk = { workspace = true, optional = true }
+tokio-util = { workspace = true, optional = true }
 futures = { workspace = true }
 once_cell = { workspace = true }
 rand = { workspace = true }
@@ -43,14 +45,16 @@ log = "0.4"
 
 
 [features]
-default = ["npubcash", "bip353"]
+default = ["npubcash", "nwc", "bip353"]
 bip353 = ["cdk/bip353"]
 # Enable Postgres-backed wallet database support in FFI
 postgres = ["cdk-postgres"]
 # Enable Supabase-backed wallet database support in FFI
 supabase = ["cdk-supabase"]
 # Enable NpubCash client bindings
 npubcash = ["cdk/npubcash", "cdk-npubcash", "nostr-sdk"]
+# Enable Nostr Wallet Connect (NIP-47) wallet service bindings
+nwc = ["cdk/nwc", "cdk-nwc", "nostr-sdk", "dep:tokio-util"]
 
 [dev-dependencies]
 

bindings/swift/rust/Cargo.toml

@@ -12,6 +12,8 @@ pub mod error;
 pub mod logging;
 #[cfg(feature = "npubcash")]
 pub mod npubcash;
+#[cfg(feature = "nwc")]
+pub mod nwc;
 #[cfg(feature = "postgres")]
 pub mod postgres;
 mod runtime;
@@ -29,6 +31,8 @@ pub use error::*;
 pub use logging::*;
 #[cfg(feature = "npubcash")]
 pub use npubcash::*;
+#[cfg(feature = "nwc")]
+pub use nwc::*;
 pub use types::*;
 pub use wallet::*;
 pub use wallet_repository::*;