feat: add support for cashu wallet (nip60 & nip61) (#71)

Reviewed-on: #71

crates/chat_ui/Cargo.toml

@@ -23,3 +23,6 @@ smallvec.workspace = true
 serde.workspace = true
 
 regex = "1"
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+nip60_ui = { path = "../nip60_ui" }

crates/chat_ui/src/lib.rs

@@ -681,6 +681,41 @@ impl ChatPanel {
         });
     }
 
+    /// Open the nutzap dialog for the room's peer; direct chats only
+    fn open_nutzap(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        #[cfg(target_arch = "wasm32")]
+        let _ = (window, cx);
+
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            let Some(room) = self.room.upgrade() else {
+                return;
+            };
+
+            let nostr = NostrRegistry::global(cx);
+            let Some(me) = nostr.read(cx).current_user() else {
+                return;
+            };
+
+            let peers: Vec<PublicKey> = room
+                .read(cx)
+                .members()
+                .iter()
+                .copied()
+                .filter(|key| *key != me)
+                .collect();
+
+            if let [recipient] = peers[..] {
+                nip60_ui::open_nutzap(window, cx, recipient, None);
+            } else {
+                window.push_notification(
+                    Notification::warning("Nutzaps can only be sent in direct chats"),
+                    cx,
+                );
+            }
+        }
+    }
+
     fn upload(&mut self, window: &mut Window, cx: &mut Context<Self>) {
         // Get the user's configured blossom server
         let server = AppSettings::get_file_server(cx);
@@ -2012,6 +2047,18 @@ impl Render for ChatPanel {
                                         this.upload(window, cx);
                                     })),
                             )
+                            .when(cfg!(not(target_arch = "wasm32")), |this| {
+                                this.child(
+                                    Button::new("nutzap")
+                                        .icon(gpui_kit::assets::IconName::Coins)
+                                        .tooltip("Send eCash")
+                                        .disabled(dictating)
+                                        .ghost()
+                                        .on_click(cx.listener(move |this, _ev, window, cx| {
+                                            this.open_nutzap(window, cx);
+                                        })),
+                                )
+                            })
                             .when(dictating, |this| {
                                 this.child(
                                     h_flex()

crates/nip60/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "nip60"
+version.workspace = true
+edition.workspace = true
+publish.workspace = true
+
+[dependencies]
+state = { path = "../state" }
+common = { path = "../common" }
+
+gpui.workspace = true
+gpui_tokio.workspace = true
+nostr.workspace = true
+nostr-sdk.workspace = true
+anyhow.workspace = true
+smallvec.workspace = true
+log.workspace = true
+flume.workspace = true
+serde_json.workspace = true
+futures.workspace = true
+hkdf.workspace = true
+sha2.workspace = true
+tokio = { version = "1", default-features = false, features = [ "rt" ] }
+
+cdk.workspace = true
+cdk-redb.workspace = true

crates/nip60/src/keys.rs

@@ -0,0 +1,369 @@
+use anyhow::{Error, anyhow};
+use hkdf::Hkdf;
+use nostr::nips::nip60::TokenEvent;
+use nostr_sdk::prelude::*;
+use sha2::Sha256;
+
+const SEED_SALT: &[u8] = b"coop nip60 seed salt";
+const SEED_INFO: &[u8] = b"coop cashu seed";
+
+/// Parsed 17375 wallet event: the wallet key and its mint list.
+#[derive(Clone)]
+pub(crate) struct WalletData {
+    pub(crate) event_id: EventId,
+    pub(crate) created_at: Timestamp,
+    pub(crate) privkey: SecretKey,
+    pub(crate) mints: Vec<Url>,
+}
+
+impl WalletData {
+    /// A new wallet with a fresh key.
+    pub(crate) fn generate(first_mint: Url) -> Self {
+        Self {
+            event_id: EventId::from_byte_array([0; 32]),
+            created_at: Timestamp::from_secs(0),
+            privkey: SecretKey::generate(),
+            mints: vec![first_mint],
+        }
+    }
+
+    /// The cdk seed, derived deterministically from the wallet key.
+    pub(crate) fn derive_seed(privkey: &SecretKey) -> Result<[u8; 64], Error> {
+        let ikm = privkey.to_secret_bytes();
+        let hk = Hkdf::<Sha256>::new(Some(SEED_SALT), &ikm);
+        let mut seed = [0u8; 64];
+        hk.expand(SEED_INFO, &mut seed)
+            .map_err(|error| anyhow!("seed derivation failed: {error}"))?;
+        Ok(seed)
+    }
+
+    /// Decrypt and parse a 17375 event published by this account.
+    pub(crate) async fn decrypt<S>(signer: &S, me: &PublicKey, event: &Event) -> Result<Self, Error>
+    where
+        S: AsyncNip44 + ?Sized,
+    {
+        if event.pubkey != *me {
+            return Err(anyhow!("wallet event was not published by this account"));
+        }
+
+        let content = signer.nip44_decrypt_async(me, &event.content).await?;
+        let (privkey, mints) = parse_wallet_content(&content)?;
+
+        Ok(Self {
+            event_id: event.id,
+            created_at: event.created_at,
+            privkey,
+            mints,
+        })
+    }
+
+    /// Build the encrypted 17375 event for this wallet data.
+    pub(crate) async fn to_event<S>(&self, signer: &S, me: &PublicKey) -> Result<Event, Error>
+    where
+        S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + ?Sized,
+    {
+        let mut rows = vec![vec!["privkey".to_string(), self.privkey.to_secret_hex()]];
+        for mint in &self.mints {
+            rows.push(vec!["mint".to_string(), mint.to_string()]);
+        }
+
+        let content = signer
+            .nip44_encrypt_async(me, &serde_json::to_string(&rows)?)
+            .await?;
+
+        Ok(EventBuilder::new(Kind::CashuWallet, content)
+            .finalize_async(signer)
+            .await?)
+    }
+}
+
+fn parse_wallet_content(content: &str) -> Result<(SecretKey, Vec<Url>), Error> {
+    let rows: Vec<Vec<String>> =
+        serde_json::from_str(content).map_err(|error| anyhow!("invalid wallet event: {error}"))?;
+
+    let mut privkey = None;
+    let mut mints = Vec::new();
+    for row in rows {
+        let (Some(key), Some(value)) = (row.first(), row.get(1)) else {
+            continue;
+        };
+        match key.as_str() {
+            "privkey" if privkey.is_none() => privkey = Some(SecretKey::from_hex(value)?),
+            "mint" => {
+                if let Ok(mint) = Url::parse(value) {
+                    mints.push(mint);
+                }
+            }
+            _ => {}
+        }
+    }
+
+    let Some(privkey) = privkey else {
+        return Err(anyhow!("wallet event is missing the private key"));
+    };
+    if mints.is_empty() {
+        return Err(anyhow!("wallet event is missing mints"));
+    }
+
+    Ok((privkey, mints))
+}
+
+pub(crate) async fn decrypt_token_event<S>(
+    signer: &S,
+    me: &PublicKey,
+    event: &Event,
+) -> Result<TokenEvent, Error>
+where
+    S: AsyncNip44 + ?Sized,
+{
+    if event.pubkey != *me {
+        return Err(anyhow!("token event was not published by this account"));
+    }
+
+    let content = signer.nip44_decrypt_async(me, &event.content).await?;
+
+    let token =
+        serde_json::from_str(&content).map_err(|error| anyhow!("invalid token event: {error}"))?;
+
+    Ok(token)
+}
+
+pub(crate) async fn build_token_event<S>(
+    signer: &S,
+    me: &PublicKey,
+    token: &TokenEvent,
+) -> Result<Event, Error>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + ?Sized,
+{
+    let content = signer
+        .nip44_encrypt_async(me, &serde_json::to_string(token)?)
+        .await?;
+
+    Ok(EventBuilder::new(Kind::CashuWalletUnspentProof, content)
+        .finalize_async(signer)
+        .await?)
+}
+
+/// NIP-09 deletion carrying the `k: 7375` tag required by NIP-60.
+pub(crate) async fn build_token_deletion<S>(signer: &S, ids: &[EventId]) -> Result<Event, Error>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + ?Sized,
+{
+    let mut tags: Vec<Tag> = ids.iter().map(|id| Tag::event(*id)).collect();
+    tags.push(Tag::custom("k", ["7375".to_string()]));
+
+    Ok(EventBuilder::new(Kind::EventDeletion, "")
+        .tags(tags)
+        .finalize_async(signer)
+        .await?)
+}
+
+/// Decrypted 7376 payload, enough for the wallet panel's history list.
+pub(crate) struct HistoryPayload {
+    pub(crate) direction: TransactionDirection,
+    pub(crate) amount: u64,
+}
+
+pub(crate) async fn decrypt_history_event<S>(
+    signer: &S,
+    me: &PublicKey,
+    event: &Event,
+) -> Result<HistoryPayload, Error>
+where
+    S: AsyncNip44 + ?Sized,
+{
+    if event.pubkey != *me {
+        return Err(anyhow!("history event was not published by this account"));
+    }
+
+    let content = signer.nip44_decrypt_async(me, &event.content).await?;
+    let rows: Vec<Vec<String>> = serde_json::from_str(&content)
+        .map_err(|error| anyhow!("invalid history event: {error}"))?;
+
+    let mut direction = None;
+    let mut amount = None;
+    for row in rows {
+        let (Some(key), Some(value)) = (row.first(), row.get(1)) else {
+            continue;
+        };
+        match key.as_str() {
+            "direction" if direction.is_none() => direction = value.parse().ok(),
+            "amount" if amount.is_none() => amount = value.parse().ok(),
+            _ => {}
+        }
+    }
+
+    let Some(direction) = direction else {
+        return Err(anyhow!("history event is missing the direction"));
+    };
+    let Some(amount) = amount else {
+        return Err(anyhow!("history event is missing the amount"));
+    };
+
+    Ok(HistoryPayload { direction, amount })
+}
+
+/// Build the public kind 9321 nutzap event carrying P2PK-locked proofs.
+pub(crate) async fn build_nutzap_event<S>(
+    signer: &S,
+    recipient: PublicKey,
+    mint: &str,
+    proofs: &[String],
+    target: Option<EventId>,
+    comment: &str,
+) -> Result<Event, Error>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + ?Sized,
+{
+    let mut tags: Vec<Tag> = vec![
+        Tag::custom("p", [recipient.to_hex()]),
+        Tag::custom("u", [mint.to_string()]),
+        Tag::custom("unit", ["sat".to_string()]),
+    ];
+
+    for proof in proofs {
+        tags.push(Tag::custom("proof", [proof.clone()]));
+    }
+
+    if let Some(target) = target {
+        tags.push(Tag::custom("e", [target.to_hex()]));
+    }
+
+    Ok(EventBuilder::new(Kind::Custom(9321), comment)
+        .tags(tags)
+        .finalize_async(signer)
+        .await?)
+}
+
+/// Encrypted 7376 history payload for one state change.
+pub(crate) struct History {
+    pub(crate) direction: TransactionDirection,
+    pub(crate) amount: u64,
+    /// NIP-61 nutzap events redeemed by this state change
+    pub(crate) redeemed: Vec<EventId>,
+    /// Author of the redeemed nutzap, for the unencrypted `p` tag
+    pub(crate) sender: Option<PublicKey>,
+}
+
+pub(crate) async fn build_history_event<S>(
+    signer: &S,
+    me: &PublicKey,
+    history: &History,
+    created: EventId,
+    destroyed: &[EventId],
+) -> Result<Event, Error>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + ?Sized,
+{
+    let mut rows = vec![
+        vec!["direction".to_string(), history.direction.to_string()],
+        vec!["amount".to_string(), history.amount.to_string()],
+    ];
+
+    for id in destroyed {
+        rows.push(vec![
+            "e".to_string(),
+            id.to_hex(),
+            String::new(),
+            "destroyed".to_string(),
+        ]);
+    }
+
+    rows.push(vec![
+        "e".to_string(),
+        created.to_hex(),
+        String::new(),
+        "created".to_string(),
+    ]);
+
+    let mut tags: Vec<Tag> = history
+        .redeemed
+        .iter()
+        .map(|id| Tag::custom("e", [id.to_hex(), String::new(), "redeemed".to_string()]))
+        .collect();
+
+    if let Some(sender) = history.sender {
+        tags.push(Tag::custom("p", [sender.to_hex()]));
+    }
+
+    let content = signer
+        .nip44_encrypt_async(me, &serde_json::to_string(&rows)?)
+        .await?;
+
+    Ok(EventBuilder::new(Kind::CashuWalletSpendingHistory, content)
+        .tags(tags)
+        .finalize_async(signer)
+        .await?)
+}
+
+pub(crate) async fn build_nutzap_info_event<S>(
+    signer: &S,
+    mints: &[Url],
+    relays: &[RelayUrl],
+    wallet_pubkey: PublicKey,
+) -> Result<Event, Error>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + ?Sized,
+{
+    let mut tags: Vec<Tag> = relays
+        .iter()
+        .map(|relay| Tag::custom("relay", [relay.to_string()]))
+        .collect();
+
+    for mint in mints {
+        tags.push(Tag::custom("mint", [mint.to_string(), "sat".to_string()]));
+    }
+
+    tags.push(Tag::custom(
+        "pubkey",
+        [format!("02{}", wallet_pubkey.to_hex())],
+    ));
+
+    Ok(EventBuilder::new(Kind::Custom(10019), "")
+        .tags(tags)
+        .finalize_async(signer)
+        .await?)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parses_wallet_content() {
+        let privkey = SecretKey::generate();
+        let mint = Url::parse("https://mint.example.com").expect("valid mint URL");
+
+        let content = serde_json::to_string(&vec![
+            vec!["privkey".to_string(), privkey.to_secret_hex()],
+            vec!["mint".to_string(), mint.to_string()],
+        ])
+        .expect("serialization cannot fail");
+
+        let (parsed_key, mints) = parse_wallet_content(&content).expect("valid content");
+        assert_eq!(parsed_key.to_secret_hex(), privkey.to_secret_hex());
+        assert_eq!(mints, vec![mint]);
+    }
+
+    #[test]
+    fn wallet_content_rejects_missing_privkey() {
+        let mint = Url::parse("https://mint.example.com").expect("valid mint URL");
+        let content = serde_json::to_string(&vec![vec!["mint".to_string(), mint.to_string()]])
+            .expect("serialization cannot fail");
+
+        assert!(parse_wallet_content(&content).is_err());
+    }
+
+    #[test]
+    fn seed_is_deterministic_per_key() {
+        let key = SecretKey::generate();
+        let first = WalletData::derive_seed(&key).expect("seed derivation cannot fail");
+        let second = WalletData::derive_seed(&key).expect("seed derivation cannot fail");
+        assert_eq!(first, second);
+
+        let other =
+            WalletData::derive_seed(&SecretKey::generate()).expect("seed derivation cannot fail");
+        assert_ne!(first, other);
+    }
+}

crates/nip60/src/ops.rs

@@ -0,0 +1,617 @@
+use std::collections::{HashMap, HashSet};
+use std::str::FromStr;
+use std::time::Duration;
+
+use anyhow::{Error, anyhow};
+use cdk::Amount;
+use cdk::amount::SplitTarget;
+use cdk::mint_url::MintUrl;
+use cdk::nuts::nut00::KnownMethod;
+use cdk::nuts::{
+    CurrencyUnit, Id, KeySetInfo, MeltQuoteState, MintQuoteState, PaymentMethod, Proof, Proofs,
+    SecretKey, SpendingConditions, State,
+};
+use cdk::secret::Secret;
+use cdk::wallet::types::ProofInfo;
+use cdk::wallet::{ReceiveOptions, SendOptions, Wallet};
+use futures::StreamExt;
+use nostr::nips::nip60::{CashuProof, TokenEvent, TransactionDirection};
+use nostr_sdk::prelude::*;
+
+use crate::keys;
+
+/// How long to wait for relays when fetching a recipient's wallet info
+const FETCH_TIMEOUT: Duration = Duration::from_secs(5);
+
+/// A job mutating the wallet store or reconciling it with relays.
+#[derive(Debug, Clone)]
+pub(crate) enum Job {
+    Reconcile,
+    CreateQuote {
+        mint: MintUrl,
+        amount: u64,
+    },
+    ClaimQuote {
+        mint: MintUrl,
+        quote_id: String,
+    },
+    Melt {
+        mint: MintUrl,
+        invoice: String,
+    },
+    SendToken {
+        mint: MintUrl,
+        amount: u64,
+    },
+    SendNutzap {
+        recipient: PublicKey,
+        amount: u64,
+        target: Option<EventId>,
+        comment: Option<String>,
+    },
+    Receive {
+        mint: MintUrl,
+        token: String,
+    },
+    RedeemNutzap {
+        mint: MintUrl,
+        proofs: Proofs,
+        nutzap_id: EventId,
+        sender: PublicKey,
+    },
+}
+
+impl Job {
+    pub(crate) async fn run<S>(self, ctx: JobCtx<S>) -> Result<Outcome, Error>
+    where
+        S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + Send + Sync + 'static,
+    {
+        match self {
+            Job::Reconcile => ctx.reconcile().await,
+            Job::CreateQuote { mint, amount } => {
+                let wallet = ctx.wallet(&mint)?;
+                let quote = wallet
+                    .mint_quote(
+                        PaymentMethod::Known(KnownMethod::Bolt11),
+                        Some(Amount::from(amount)),
+                        None,
+                        None,
+                    )
+                    .await?;
+
+                Ok(Outcome::QuoteCreated {
+                    mint,
+                    quote_id: quote.id,
+                    request: quote.request,
+                    amount,
+                })
+            }
+            Job::ClaimQuote { mint, quote_id } => {
+                let wallet = ctx.wallet(&mint)?;
+                let quote = wallet.check_mint_quote(&quote_id).await?;
+
+                if quote.state != MintQuoteState::Paid {
+                    return Ok(Outcome::Idle);
+                }
+
+                let proofs = wallet.mint(&quote_id, SplitTarget::default(), None).await?;
+                let amount: u64 = proofs.iter().map(|proof| u64::from(proof.amount)).sum();
+
+                let update = ctx
+                    .sync_token_events(
+                        wallet,
+                        nostr_mint(&mint)?,
+                        &ctx.previous_ids(&mint),
+                        Some(keys::History {
+                            direction: TransactionDirection::In,
+                            amount: u64::from(quote.amount.unwrap_or_default()),
+                            redeemed: Vec::new(),
+                            sender: None,
+                        }),
+                    )
+                    .await?;
+
+                Ok(Outcome::QuoteMinted {
+                    quote_id,
+                    update,
+                    amount,
+                })
+            }
+            Job::Melt { mint, invoice } => {
+                let wallet = ctx.wallet(&mint)?;
+                let quote = wallet
+                    .melt_quote(
+                        PaymentMethod::Known(KnownMethod::Bolt11),
+                        invoice,
+                        None,
+                        None,
+                    )
+                    .await?;
+
+                let finalized = wallet
+                    .prepare_melt(&quote.id, HashMap::new())
+                    .await?
+                    .confirm()
+                    .await?;
+
+                if finalized.state() != MeltQuoteState::Paid {
+                    return Err(anyhow!("melt did not settle: {:?}", finalized.state()));
+                }
+
+                let amount = u64::from(finalized.total_amount());
+                let update = ctx
+                    .sync_token_events(
+                        wallet,
+                        nostr_mint(&mint)?,
+                        &ctx.previous_ids(&mint),
+                        Some(keys::History {
+                            direction: TransactionDirection::Out,
+                            amount,
+                            redeemed: Vec::new(),
+                            sender: None,
+                        }),
+                    )
+                    .await?;
+
+                Ok(Outcome::Melted { update, amount })
+            }
+            Job::SendToken { mint, amount } => {
+                let wallet = ctx.wallet(&mint)?;
+                let prepared = wallet
+                    .prepare_send(Amount::from(amount), SendOptions::default())
+                    .await?;
+                let token = prepared.confirm(None).await?.to_string();
+
+                let update = ctx
+                    .sync_token_events(
+                        wallet,
+                        nostr_mint(&mint)?,
+                        &ctx.previous_ids(&mint),
+                        Some(keys::History {
+                            direction: TransactionDirection::Out,
+                            amount,
+                            redeemed: Vec::new(),
+                            sender: None,
+                        }),
+                    )
+                    .await?;
+
+                Ok(Outcome::Sent { update, token })
+            }
+            Job::SendNutzap {
+                recipient,
+                amount,
+                target,
+                comment,
+            } => {
+                let (mint_url, mint_tag, p2pk) = recipient_wallet_info(&ctx, recipient).await?;
+                let wallet = ctx.wallet(&mint_url)?;
+
+                let keysets = wallet
+                    .keysets(cdk::wallet::types::KeysetLoadPolicy::CacheOnly)
+                    .await?;
+
+                let infos: Vec<KeySetInfo> = keysets
+                    .iter()
+                    .map(|keyset| KeySetInfo {
+                        id: keyset.id,
+                        unit: keyset.unit.clone(),
+                        active: keyset.active.unwrap_or(true),
+                        input_fee_ppk: keyset.input_fee_ppk,
+                        final_expiry: keyset.final_expiry,
+                    })
+                    .collect();
+
+                let options = SendOptions {
+                    conditions: Some(SpendingConditions::new_p2pk(p2pk, None)),
+                    ..Default::default()
+                };
+
+                let token = wallet
+                    .prepare_send(Amount::from(amount), options)
+                    .await?
+                    .confirm(None)
+                    .await?;
+                let proofs = token.proofs(&infos)?;
+
+                let mut tags = Vec::new();
+                for proof in &proofs {
+                    tags.push(serde_json::to_string(proof)?);
+                }
+
+                let event = keys::build_nutzap_event(
+                    &ctx.signer,
+                    recipient,
+                    &mint_tag,
+                    &tags,
+                    target,
+                    comment.as_deref().unwrap_or(""),
+                )
+                .await?;
+                ctx.client.send_event(&event).await?;
+
+                let update = ctx
+                    .sync_token_events(
+                        wallet,
+                        nostr_mint(&mint_url)?,
+                        &ctx.previous_ids(&mint_url),
+                        Some(keys::History {
+                            direction: TransactionDirection::Out,
+                            amount,
+                            redeemed: Vec::new(),
+                            sender: None,
+                        }),
+                    )
+                    .await?;
+
+                Ok(Outcome::NutzapSent { update, amount })
+            }
+            Job::Receive { mint, token } => {
+                let wallet = ctx.wallet(&mint)?;
+                let received = wallet.receive(&token, ReceiveOptions::default()).await?;
+
+                let update = ctx
+                    .sync_token_events(
+                        wallet,
+                        nostr_mint(&mint)?,
+                        &ctx.previous_ids(&mint),
+                        Some(keys::History {
+                            direction: TransactionDirection::In,
+                            amount: u64::from(received),
+                            redeemed: Vec::new(),
+                            sender: None,
+                        }),
+                    )
+                    .await?;
+
+                Ok(Outcome::Received {
+                    update,
+                    amount: u64::from(received),
+                })
+            }
+            Job::RedeemNutzap {
+                mint,
+                proofs,
+                nutzap_id,
+                sender,
+            } => {
+                let wallet = ctx.wallet(&mint)?;
+                let options = ReceiveOptions {
+                    p2pk_signing_keys: vec![ctx.wallet_key.clone()],
+                    ..Default::default()
+                };
+                let received = wallet.receive_proofs(proofs, options, None, None).await?;
+
+                let update = ctx
+                    .sync_token_events(
+                        wallet,
+                        nostr_mint(&mint)?,
+                        &ctx.previous_ids(&mint),
+                        Some(keys::History {
+                            direction: TransactionDirection::In,
+                            amount: u64::from(received),
+                            redeemed: vec![nutzap_id],
+                            sender: Some(sender),
+                        }),
+                    )
+                    .await?;
+
+                Ok(Outcome::NutzapRedeemed {
+                    update,
+                    nutzap_id,
+                    amount: u64::from(received),
+                })
+            }
+        }
+    }
+}
+
+pub(crate) struct TokenUpdate {
+    pub(crate) event_id: EventId,
+    pub(crate) token: TokenEvent,
+    pub(crate) destroyed: Vec<EventId>,
+}
+
+pub(crate) enum Outcome {
+    /// Nothing changed (e.g. an unpaid quote)
+    Idle,
+    /// Token events published by a reconcile pass
+    Reconciled {
+        updates: Vec<TokenUpdate>,
+    },
+    QuoteCreated {
+        mint: MintUrl,
+        quote_id: String,
+        request: String,
+        amount: u64,
+    },
+    QuoteMinted {
+        quote_id: String,
+        update: TokenUpdate,
+        amount: u64,
+    },
+    Melted {
+        update: TokenUpdate,
+        amount: u64,
+    },
+    Sent {
+        update: TokenUpdate,
+        token: String,
+    },
+    NutzapSent {
+        update: TokenUpdate,
+        amount: u64,
+    },
+    Received {
+        update: TokenUpdate,
+        amount: u64,
+    },
+    NutzapRedeemed {
+        update: TokenUpdate,
+        nutzap_id: EventId,
+        amount: u64,
+    },
+}
+
+pub(crate) struct JobCtx<S> {
+    pub(crate) wallets: HashMap<MintUrl, Wallet>,
+    /// Wallet signing key, unlocking P2PK-locked nutzap proofs
+    pub(crate) wallet_key: SecretKey,
+    pub(crate) signer: S,
+    pub(crate) client: Client,
+    /// Relay token events at schedule time.
+    pub(crate) tokens: HashMap<EventId, TokenEvent>,
+}
+
+impl<S> JobCtx<S>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + Sync,
+{
+    fn wallet(&self, mint: &MintUrl) -> Result<&Wallet, Error> {
+        self.wallets
+            .get(mint)
+            .ok_or_else(|| anyhow!("no open wallet for mint {mint}"))
+    }
+
+    fn previous_ids(&self, mint: &MintUrl) -> Vec<EventId> {
+        previous_ids(&self.tokens, mint)
+    }
+
+    /// Publish the store's current unspent set as a fresh token event.
+    async fn sync_token_events(
+        &self,
+        wallet: &Wallet,
+        mint: Url,
+        previous: &[EventId],
+        history: Option<keys::History>,
+    ) -> Result<TokenUpdate, Error> {
+        let me = self.signer.get_public_key_async().await?;
+        let unspent = wallet.get_unspent_proofs().await?;
+
+        let proofs = unspent
+            .iter()
+            .map(cashu_proof)
+            .collect::<Result<Vec<_>, _>>()?;
+
+        let mut token = TokenEvent::new(mint, proofs);
+        token.del = previous.iter().map(|id| id.to_hex()).collect();
+        let event = keys::build_token_event(&self.signer, &me, &token).await?;
+        self.client.send_event(&event).await?;
+
+        if !previous.is_empty() {
+            let deletion = keys::build_token_deletion(&self.signer, previous).await?;
+            self.client.send_event(&deletion).await?;
+        }
+
+        if let Some(history) = history {
+            let history_event =
+                keys::build_history_event(&self.signer, &me, &history, event.id, previous).await?;
+            self.client.send_event(&history_event).await?;
+        }
+
+        Ok(TokenUpdate {
+            event_id: event.id,
+            token,
+            destroyed: previous.to_vec(),
+        })
+    }
+
+    /// Claim paid quotes, then converge each mint.
+    async fn reconcile(self) -> Result<Outcome, Error> {
+        let mut tokens = self.tokens.clone();
+        let mut updates = Vec::new();
+
+        for (mint_url, wallet) in &self.wallets {
+            if let Err(error) = wallet.recover_incomplete_sagas().await {
+                log::warn!("saga recovery failed for {mint_url}: {error:#}");
+            }
+
+            let minted = wallet.mint_unissued_quotes().await?;
+            if minted == Amount::ZERO {
+                continue;
+            }
+
+            let update = self
+                .sync_token_events(
+                    wallet,
+                    nostr_mint(mint_url)?,
+                    &previous_ids(&tokens, mint_url),
+                    Some(keys::History {
+                        direction: TransactionDirection::In,
+                        amount: u64::from(minted),
+                        redeemed: Vec::new(),
+                        sender: None,
+                    }),
+                )
+                .await?;
+
+            for id in &update.destroyed {
+                tokens.remove(id);
+            }
+            tokens.insert(update.event_id, update.token.clone());
+            updates.push(update);
+        }
+
+        for (mint_url, wallet) in &self.wallets {
+            let mut relay_ys = HashSet::new();
+            let mut added = Vec::new();
+
+            for token in tokens
+                .values()
+                .filter(|token| token.mint.as_str() == mint_url.to_string())
+            {
+                for proof in &token.proofs {
+                    let info = match proof_info(proof, mint_url) {
+                        Ok(info) => info,
+                        Err(error) => {
+                            log::warn!("skipping proof: {error:#}");
+                            continue;
+                        }
+                    };
+                    if relay_ys.insert(info.y) {
+                        added.push(info);
+                    }
+                }
+            }
+
+            let unspent = wallet.get_unspent_proofs().await?;
+            let removed = unspent
+                .iter()
+                .filter(|proof| match proof.y() {
+                    Ok(y) => !relay_ys.contains(&y),
+                    Err(_) => false,
+                })
+                .map(|proof| proof.y())
+                .collect::<Result<Vec<_>, _>>()?;
+
+            wallet.localstore.update_proofs(added, removed).await?;
+        }
+
+        Ok(Outcome::Reconciled { updates })
+    }
+}
+
+fn previous_ids(tokens: &HashMap<EventId, TokenEvent>, mint: &MintUrl) -> Vec<EventId> {
+    tokens
+        .iter()
+        .filter(|(_, token)| token.mint.as_str() == mint.to_string())
+        .map(|(id, _)| *id)
+        .collect()
+}
+
+/// Resolve a recipient's 10019 wallet info and pick a mint we share with them.
+async fn recipient_wallet_info<S>(
+    ctx: &JobCtx<S>,
+    recipient: PublicKey,
+) -> Result<(MintUrl, String, cdk::nuts::PublicKey), Error>
+where
+    S: AsyncGetPublicKey + AsyncSignEvent + AsyncNip44 + Sync,
+{
+    let filter = Filter::new()
+        .author(recipient)
+        .kind(Kind::Custom(10019))
+        .limit(1);
+
+    let info = match ctx
+        .client
+        .database()
+        .query(filter.clone())
+        .await?
+        .into_iter()
+        .next()
+    {
+        Some(event) => event,
+        None => {
+            let mut stream = ctx
+                .client
+                .stream_events(filter)
+                .timeout(FETCH_TIMEOUT)
+                .await?;
+            let mut found: Option<Event> = None;
+
+            while let Some((_url, result)) = stream.next().await {
+                if let Ok(event) = result {
+                    let newer = found
+                        .as_ref()
+                        .is_none_or(|current| event.created_at > current.created_at);
+
+                    if newer {
+                        found = Some(event);
+                    }
+                }
+            }
+
+            found.ok_or_else(|| anyhow!("recipient has no wallet info"))?
+        }
+    };
+
+    let (p2pk, mints) = parse_nutzap_info(&info)?;
+
+    for mint in mints {
+        let Ok(mint_url) = MintUrl::from_str(&mint) else {
+            continue;
+        };
+
+        if ctx.wallets.contains_key(&mint_url) {
+            return Ok((mint_url, mint, p2pk));
+        }
+    }
+
+    Err(anyhow!("no shared mint with the recipient"))
+}
+
+fn parse_nutzap_info(event: &Event) -> Result<(cdk::nuts::PublicKey, Vec<String>), Error> {
+    let mut p2pk = None;
+    let mut mints = Vec::new();
+
+    for tag in event.tags.iter() {
+        let Some(value) = tag.content() else {
+            continue;
+        };
+
+        match tag.kind() {
+            "pubkey" if p2pk.is_none() => {
+                p2pk = Some(cdk::nuts::PublicKey::from_str(value)?);
+            }
+            "mint" => mints.push(value.to_string()),
+            _ => {}
+        }
+    }
+
+    let Some(p2pk) = p2pk else {
+        return Err(anyhow!("recipient has no wallet pubkey"));
+    };
+
+    Ok((p2pk, mints))
+}
+
+fn cashu_proof(proof: &Proof) -> Result<CashuProof, Error> {
+    Ok(CashuProof {
+        id: proof.keyset_id.to_string(),
+        amount: u64::from(proof.amount),
+        secret: proof.secret.to_string(),
+        c: proof.c.to_string(),
+    })
+}
+
+fn nostr_mint(mint: &MintUrl) -> Result<Url, Error> {
+    Url::parse(&mint.to_string()).map_err(|error| anyhow!("invalid mint url: {error}"))
+}
+
+fn proof_info(proof: &CashuProof, mint: &MintUrl) -> Result<ProofInfo, Error> {
+    let keyset_id = Id::from_str(&proof.id)?;
+    let c = cdk::nuts::PublicKey::from_str(&proof.c)?;
+    let info = ProofInfo::new(
+        Proof::new(
+            Amount::from(proof.amount),
+            keyset_id,
+            Secret::new(proof.secret.clone()),
+            c,
+        ),
+        mint.clone(),
+        State::Unspent,
+        CurrencyUnit::Sat,
+    )?;
+
+    Ok(info)
+}

crates/nip60_ui/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "nip60_ui"
+version.workspace = true
+edition.workspace = true
+publish.workspace = true
+
+[dependencies]
+common = { path = "../common" }
+nip60 = { path = "../nip60" }
+person = { path = "../person" }
+settings = { path = "../settings" }
+state = { path = "../state" }
+ui = { path = "../ui" }
+
+gpui.workspace = true
+gpui-kit.workspace = true
+nostr-sdk.workspace = true
+anyhow.workspace = true
+smallvec.workspace = true

crates/nip60_ui/src/lib.rs

@@ -0,0 +1,77 @@
+#![cfg(not(target_arch = "wasm32"))]
+
+use std::rc::Rc;
+
+use gpui::{App, AppContext, ClickEvent, ParentElement, Styled, Window, px};
+use gpui_kit::component::button::{Button, ButtonVariants};
+use gpui_kit::component::input::{Input, InputState};
+use gpui_kit::component::notification::Notification;
+use gpui_kit::component::{WindowExt, h_flex, v_flex};
+use nip60::WalletRegistry;
+use nostr_sdk::prelude::{EventId, PublicKey};
+
+pub mod wallet;
+
+type SubmitFn = Rc<dyn Fn(&ClickEvent, &mut Window, &mut App) -> bool>;
+
+pub fn open_nutzap(
+    window: &mut Window,
+    cx: &mut App,
+    recipient: PublicKey,
+    target: Option<EventId>,
+) {
+    let input = cx.new(|cx| InputState::new(window, cx).placeholder("Amount (sats)"));
+
+    let send: SubmitFn = {
+        let input = input.clone();
+        Rc::new(move |_, window, cx| {
+            let amount = match input.read(cx).value().trim().parse::<u64>() {
+                Ok(amount) if amount > 0 => amount,
+                _ => {
+                    window.push_notification(Notification::error("Enter an amount in sats"), cx);
+                    return false;
+                }
+            };
+
+            let wallet = WalletRegistry::global(cx);
+            wallet.update(cx, |registry, cx| {
+                registry.send_nutzap(recipient, amount, target, None, cx);
+            });
+
+            true
+        })
+    };
+
+    window.open_dialog(cx, move |this, _window, _cx| {
+        this.width(px(380.))
+            .title("Send Nutzap")
+            .on_ok({
+                let send = send.clone();
+                move |event, window, cx| send(event, window, cx)
+            })
+            .child(
+                v_flex()
+                    .gap_3()
+                    .child(Input::new(&input).cleanable(true))
+                    .child(
+                        h_flex()
+                            .gap_1()
+                            .justify_end()
+                            .child(
+                                Button::new("cancel")
+                                    .label("Cancel")
+                                    .ghost()
+                                    .on_click(|_, window, cx| window.close_dialog(cx)),
+                            )
+                            .child(Button::new("send").label("Send").primary().on_click({
+                                let send = send.clone();
+                                move |event, window, cx| {
+                                    if send(event, window, cx) {
+                                        window.close_dialog(cx);
+                                    }
+                                }
+                            })),
+                    ),
+            )
+    });
+}

crates/nip60_ui/src/wallet.rs

@@ -0,0 +1,787 @@
+use std::ops::Range;
+use std::rc::Rc;
+
+use ::nip60::{HistoryEntry, WalletEvent, WalletRegistry};
+use common::TimestampExt;
+use gpui::prelude::FluentBuilder;
+use gpui::{
+    AnyElement, App, AppContext, ClickEvent, Context, Entity, EventEmitter, FocusHandle, Focusable,
+    InteractiveElement as _, IntoElement, ParentElement, Render, SharedString,
+    StatefulInteractiveElement as _, Styled, Subscription, Task, Window, div, px, relative,
+    uniform_list,
+};
+use gpui_kit::assets::IconName;
+use gpui_kit::base::StyledExt as _;
+use gpui_kit::component::button::{Button, ButtonVariants as _};
+use gpui_kit::component::dock::{Panel, PanelEvent};
+use gpui_kit::component::input::{Input, InputEvent, InputState, NumberInput};
+use gpui_kit::component::notification::Notification;
+use gpui_kit::component::separator::Separator;
+use gpui_kit::component::{
+    ActiveTheme, Disableable as _, Icon, Sizable, WindowExt, h_flex, v_flex,
+};
+use nostr_sdk::prelude::*;
+use person::Directory;
+use settings::AppSettings;
+use smallvec::SmallVec;
+use state::NostrRegistry;
+use ui::Avatar;
+
+pub fn init(window: &mut Window, cx: &mut App) -> Entity<WalletPanel> {
+    cx.new(|cx| WalletPanel::new(window, cx))
+}
+
+type SubmitFn = Rc<dyn Fn(&ClickEvent, &mut Window, &mut App) -> bool>;
+
+pub struct WalletPanel {
+    name: SharedString,
+    focus_handle: FocusHandle,
+    _subscriptions: SmallVec<[Subscription; 1]>,
+}
+
+impl WalletPanel {
+    fn new(window: &mut Window, cx: &mut Context<Self>) -> Self {
+        let wallet = WalletRegistry::global(cx);
+        let mut subscriptions = SmallVec::new();
+        subscriptions.push(cx.subscribe_in(
+            &wallet,
+            window,
+            |_this, _wallet, event, window, cx| match event {
+                WalletEvent::Updated => cx.notify(),
+                WalletEvent::Error(error) => {
+                    window.push_notification(Notification::error(error.clone()), cx);
+                }
+                WalletEvent::TokenCreated(_) => {}
+            },
+        ));
+
+        Self {
+            name: "Wallet".into(),
+            focus_handle: cx.focus_handle(),
+            _subscriptions: subscriptions,
+        }
+    }
+
+    fn render_balance(&self, cx: &Context<Self>) -> impl IntoElement {
+        let balance = WalletRegistry::global(cx).read(cx).balance();
+
+        h_flex()
+            .justify_center()
+            .items_baseline()
+            .gap_2()
+            .child(
+                div()
+                    .text_3xl()
+                    .line_height(relative(1.0))
+                    .child(SharedString::from(balance.to_string())),
+            )
+            .child(
+                div()
+                    .italic()
+                    .line_height(relative(1.0))
+                    .text_color(cx.theme().muted_foreground)
+                    .child("sats"),
+            )
+    }
+
+    fn render_actions(&self) -> impl IntoElement {
+        h_flex().w_full().justify_center().child(
+            h_flex()
+                .w_80()
+                .gap_2()
+                .child(
+                    Button::new("send")
+                        .label("Send")
+                        .secondary()
+                        .rounded_full()
+                        .flex_1()
+                        .on_click(|_, window, cx| open_send_dialog(window, cx)),
+                )
+                .child(
+                    Button::new("receive")
+                        .label("Receive")
+                        .secondary()
+                        .rounded_full()
+                        .flex_1()
+                        .on_click(|_, window, cx| open_receive_dialog(window, cx)),
+                ),
+        )
+    }
+
+    fn render_history(
+        &mut self,
+        history: Vec<HistoryEntry>,
+        cx: &mut Context<Self>,
+    ) -> impl IntoElement {
+        if history.is_empty() {
+            return v_flex()
+                .items_center()
+                .justify_center()
+                .h_32()
+                .w_full()
+                .text_xs()
+                .text_color(cx.theme().muted_foreground)
+                .border_1()
+                .border_dashed()
+                .border_color(cx.theme().border)
+                .rounded(cx.theme().radius_lg)
+                .child("No transactions yet.")
+                .into_any_element();
+        }
+
+        uniform_list(
+            "wallet-history",
+            history.len(),
+            cx.processor(move |this, range, _window, cx| {
+                this.render_history_rows(range, &history, cx)
+            }),
+        )
+        .flex_1()
+        .min_h_0()
+        .into_any_element()
+    }
+
+    fn render_history_rows(
+        &self,
+        range: std::ops::Range<usize>,
+        history: &[HistoryEntry],
+        cx: &Context<Self>,
+    ) -> Vec<AnyElement> {
+        range
+            .map(|ix| {
+                self.render_history_entry(&history[ix], cx)
+                    .into_any_element()
+            })
+            .collect()
+    }
+
+    fn render_history_entry(&self, entry: &HistoryEntry, cx: &Context<Self>) -> impl IntoElement {
+        let (label, color) = match entry.direction {
+            TransactionDirection::In => ("Received", cx.theme().success),
+            TransactionDirection::Out => ("Sent", cx.theme().danger),
+        };
+
+        h_flex()
+            .justify_between()
+            .w_full()
+            .py_0p5()
+            .text_xs()
+            .child(
+                h_flex()
+                    .gap_2()
+                    .child(div().text_color(color).child(label))
+                    .child(SharedString::from(format!("{} sats", entry.amount))),
+            )
+            .child(
+                div()
+                    .text_color(cx.theme().muted_foreground)
+                    .child(entry.created_at.to_human_time()),
+            )
+    }
+}
+
+/// Pick a contact and an amount, then send a NIP-61 nutzap
+fn open_send_dialog(window: &mut Window, cx: &mut App) {
+    let view = cx.new(|cx| SendDialog::new(window, cx));
+
+    window.open_dialog(cx, {
+        let view = view.clone();
+        move |this, _window, _cx| this.width(px(420.)).title("Send eCash").child(view.clone())
+    });
+}
+
+struct SendDialog {
+    /// Search input, filters contacts or accepts an npub / NIP-05 address
+    input: Entity<InputState>,
+    amount_input: Entity<InputState>,
+    /// Current user's contacts
+    contacts: Option<Vec<PublicKey>>,
+    /// Person directory for contact names and avatars
+    directory: Entity<Directory>,
+    /// The contact chosen to receive the nutzap
+    selected: Option<PublicKey>,
+    /// Whether a NIP-05 address is being resolved
+    resolving: bool,
+    error: Option<SharedString>,
+    tasks: Vec<Task<Result<(), anyhow::Error>>>,
+    _subscriptions: Vec<Subscription>,
+}
+
+impl SendDialog {
+    fn new(window: &mut Window, cx: &mut Context<Self>) -> Self {
+        let input = cx.new(|cx| {
+            InputState::new(window, cx).placeholder("Search or enter npub or user@address.me")
+        });
+        let amount_input = cx.new(|cx| {
+            InputState::new(window, cx)
+                .placeholder("Amount (sats)")
+                .step(1.)
+                .min(1.)
+        });
+
+        let subscriptions = vec![
+            cx.subscribe_in(&input, window, |this, _input, event, window, cx| {
+                if let InputEvent::PressEnter { .. } = event {
+                    this.submit(window, cx);
+                }
+            }),
+            cx.subscribe_in(&amount_input, window, |this, _input, event, window, cx| {
+                if let InputEvent::PressEnter { .. } = event {
+                    this.send(window, cx);
+                }
+            }),
+        ];
+
+        // Load the contacts once the view is mounted
+        cx.defer_in(window, |this, window, cx| {
+            this.load_contacts(window, cx);
+        });
+
+        Self {
+            input,
+            amount_input,
+            contacts: None,
+            directory: Directory::new(cx),
+            selected: None,
+            resolving: false,
+            error: None,
+            tasks: Vec::new(),
+            _subscriptions: subscriptions,
+        }
+    }
+
+    /// Load the signed-in user's contact list.
+    fn load_contacts(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        if self.contacts.is_some() {
+            return;
+        }
+
+        let nostr = NostrRegistry::global(cx);
+        let client = nostr.read(cx).client();
+
+        let Some(current_user) = nostr.read(cx).current_user() else {
+            return;
+        };
+
+        let task: Task<Result<Vec<PublicKey>, anyhow::Error>> = cx.background_spawn(async move {
+            let filter = Filter::new()
+                .author(current_user)
+                .kind(Kind::ContactList)
+                .limit(1);
+
+            let contacts: Vec<PublicKey> = client
+                .database()
+                .query(filter)
+                .await?
+                .into_iter()
+                .next()
+                .map(|event| event.tags.public_keys().collect())
+                .unwrap_or_default();
+
+            Ok(contacts)
+        });
+
+        self.tasks.push(cx.spawn_in(window, async move |this, cx| {
+            let contacts = task.await;
+
+            this.update_in(cx, |this, _window, cx| {
+                match contacts {
+                    Ok(contacts) => {
+                        this.directory.update(cx, |directory, cx| {
+                            directory.track(contacts.iter().copied(), cx)
+                        });
+                        this.contacts = Some(contacts);
+                    }
+                    Err(error) => this.set_error(error.to_string(), cx),
+                }
+                cx.notify();
+            })?;
+
+            Ok(())
+        }));
+    }
+
+    /// The contacts matching the current input, or every contact when empty.
+    fn filtered_contacts(&self, cx: &Context<Self>) -> Vec<PublicKey> {
+        let Some(contacts) = self.contacts.as_ref() else {
+            return Vec::new();
+        };
+
+        let query = self.input.read(cx).value().trim().to_lowercase();
+
+        if query.is_empty() {
+            return contacts.clone();
+        }
+
+        contacts
+            .iter()
+            .filter(|public_key| {
+                if public_key.to_hex().to_lowercase().contains(&query) {
+                    return true;
+                }
+
+                let name = self.directory.read(cx).person(public_key, cx).name();
+                name.to_lowercase().contains(&query)
+            })
+            .cloned()
+            .collect()
+    }
+
+    /// Resolve the input into a contact selection.
+    fn submit(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        if self.resolving {
+            return;
+        }
+
+        let query = self.input.read(cx).value().trim().to_string();
+
+        if query.is_empty() {
+            return;
+        }
+
+        // A raw public key or an npub can be selected directly.
+        if let Ok(public_key) = PublicKey::parse(&query) {
+            self.select(public_key, cx);
+            self.clear_input(window, cx);
+            return;
+        }
+
+        // A NIP-05 address is resolved before being selected.
+        if let Ok(address) = Nip05Address::parse(&query) {
+            let nostr = NostrRegistry::global(cx);
+            let task = nostr.read(cx).query_address(address, cx);
+
+            self.set_resolving(true, window, cx);
+
+            self.tasks.push(cx.spawn_in(window, async move |this, cx| {
+                let result = task.await;
+
+                this.update_in(cx, |this, window, cx| {
+                    this.set_resolving(false, window, cx);
+
+                    match result {
+                        Ok(public_key) => {
+                            this.select(public_key, cx);
+                            this.clear_input(window, cx);
+                        }
+                        Err(error) => this.set_error(error.to_string(), cx),
+                    }
+                })?;
+
+                Ok(())
+            }));
+
+            return;
+        }
+
+        // Fall back to a local search by contact name.
+        let matches = self.filtered_contacts(cx);
+        match matches.len() {
+            0 => self.set_error("Enter a valid npub or NIP-05 address", cx),
+            1 => {
+                let public_key = matches[0];
+                self.select(public_key, cx);
+                self.clear_input(window, cx);
+            }
+            _ => self.set_error("Multiple contacts match, pick one from the list", cx),
+        }
+    }
+
+    /// Select a single recipient for the nutzap.
+    fn select(&mut self, public_key: PublicKey, cx: &mut Context<Self>) {
+        let nostr = NostrRegistry::global(cx);
+
+        if nostr.read(cx).current_user() == Some(public_key) {
+            self.set_error("You cannot send to yourself", cx);
+            return;
+        }
+
+        self.directory
+            .update(cx, |directory, cx| directory.track([public_key], cx));
+        self.selected = Some(public_key);
+        self.error = None;
+        cx.notify();
+    }
+
+    /// Toggle a contact's selection.
+    fn toggle_selection(&mut self, public_key: &PublicKey, cx: &mut Context<Self>) {
+        if self.selected == Some(*public_key) {
+            self.selected = None;
+            cx.notify();
+        } else {
+            self.select(*public_key, cx);
+        }
+    }
+
+    /// Validate the selection and amount, then schedule the nutzap.
+    fn send(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> bool {
+        let Some(recipient) = self.selected else {
+            self.set_error("Select a contact to send to", cx);
+            return false;
+        };
+
+        let Some(amount) = parse_amount(&self.amount_input, cx) else {
+            self.set_error("Enter an amount in sats", cx);
+            return false;
+        };
+
+        WalletRegistry::global(cx).update(cx, |registry, cx| {
+            registry.send_nutzap(recipient, amount, None, None, cx);
+        });
+
+        true
+    }
+
+    fn clear_input(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        self.input.update(cx, |this, cx| {
+            this.set_value("", window, cx);
+        });
+    }
+
+    /// Toggle the input's loading spinner while a NIP-05 address is resolved.
+    fn set_resolving(&mut self, resolving: bool, window: &mut Window, cx: &mut Context<Self>) {
+        self.input.update(cx, |this, cx| {
+            this.set_loading(resolving, window, cx);
+        });
+        self.resolving = resolving;
+        cx.notify();
+    }
+
+    fn set_error(&mut self, message: impl Into<SharedString>, cx: &mut Context<Self>) {
+        self.error = Some(message.into());
+        cx.notify();
+    }
+
+    fn render_contacts(
+        &self,
+        range: Range<usize>,
+        contacts: &[PublicKey],
+        cx: &mut Context<Self>,
+    ) -> Vec<AnyElement> {
+        contacts
+            .get(range)
+            .into_iter()
+            .flatten()
+            .map(|public_key| {
+                let profile = self.directory.read(cx).person(public_key, cx);
+                let public_key = *public_key;
+                let selected = self.selected == Some(public_key);
+                let id = SharedString::from(format!("contact-{}", public_key.to_hex()));
+
+                h_flex()
+                    .id(id)
+                    .w_full()
+                    .h_8()
+                    .px_2()
+                    .gap_2()
+                    .rounded(cx.theme().radius)
+                    .text_sm()
+                    .cursor_pointer()
+                    .hover(|this| this.bg(cx.theme().list_hover))
+                    .when(selected, |this| this.bg(cx.theme().list_active))
+                    .when(!AppSettings::get_hide_avatar(cx), |this| {
+                        this.child(
+                            Avatar::new(profile.avatar())
+                                .seed(profile.avatar_seed())
+                                .small(),
+                        )
+                    })
+                    .child(div().min_w_0().truncate().child(profile.name()))
+                    .on_click(cx.listener(move |this, _event, _window, cx| {
+                        this.toggle_selection(&public_key, cx);
+                    }))
+                    .into_any_element()
+            })
+            .collect()
+    }
+
+    fn render_selected(&self, cx: &mut Context<Self>) -> impl IntoElement {
+        let Some(public_key) = self.selected else {
+            return div().into_any_element();
+        };
+
+        let profile = self.directory.read(cx).person(&public_key, cx);
+        let id = SharedString::from(format!("selected-{}", public_key.to_hex()));
+
+        h_flex()
+            .gap_1()
+            .child(
+                h_flex()
+                    .id(id)
+                    .gap_1()
+                    .p_0p5()
+                    .rounded_full()
+                    .bg(cx.theme().secondary)
+                    .hover(|this| this.bg(cx.theme().primary))
+                    .child(
+                        Avatar::new(profile.avatar())
+                            .seed(profile.avatar_seed())
+                            .xsmall(),
+                    )
+                    .child(
+                        div()
+                            .max_w_32()
+                            .truncate()
+                            .text_xs()
+                            .line_height(relative(1.0))
+                            .child(profile.name()),
+                    )
+                    .on_click(cx.listener(move |this, _event, _window, cx| {
+                        this.selected = None;
+                        cx.notify();
+                    })),
+            )
+            .into_any_element()
+    }
+}
+
+impl Render for SendDialog {
+    fn render(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        const NOTICE: &str = "Recipients need a NIP-60 wallet on a mint you both use.";
+
+        let contacts = Rc::new(self.filtered_contacts(cx));
+        let contact_count = contacts.len();
+
+        v_flex()
+            .gap_3()
+            .child(NumberInput::new(&self.amount_input))
+            .child(
+                h_flex()
+                    .gap_1()
+                    .w_full()
+                    .child(Input::new(&self.input).flex_1().cleanable(true))
+                    .child(
+                        Button::new("add")
+                            .icon(IconName::Plus)
+                            .tooltip("Add person")
+                            .ghost()
+                            .large()
+                            .disabled(self.resolving)
+                            .on_click(cx.listener(|this, _event, window, cx| {
+                                this.submit(window, cx);
+                            })),
+                    ),
+            )
+            .when(self.selected.is_some(), |this| {
+                this.child(self.render_selected(cx))
+            })
+            .child(
+                uniform_list(
+                    "send-contacts",
+                    contact_count,
+                    cx.processor(move |this, range, _window, cx| {
+                        this.render_contacts(range, contacts.as_slice(), cx)
+                    }),
+                )
+                .h_64(),
+            )
+            .map(|this| {
+                if let Some(error) = self.error.clone() {
+                    this.child(div().text_xs().text_color(cx.theme().danger).child(error))
+                } else {
+                    this.child(
+                        div()
+                            .text_xs()
+                            .text_color(cx.theme().muted_foreground)
+                            .child(NOTICE),
+                    )
+                }
+            })
+            .child(
+                h_flex()
+                    .gap_1()
+                    .justify_end()
+                    .child(
+                        Button::new("cancel")
+                            .label("Cancel")
+                            .secondary()
+                            .on_click(|_, window, cx| window.close_dialog(cx)),
+                    )
+                    .child(
+                        Button::new("send")
+                            .label("Send")
+                            .primary()
+                            .on_click(cx.listener(move |this, _event, window, cx| {
+                                if this.send(window, cx) {
+                                    window.close_dialog(cx);
+                                }
+                            })),
+                    ),
+            )
+    }
+}
+
+/// Create a lightning invoice or redeem a pasted cashu token
+fn open_receive_dialog(window: &mut Window, cx: &mut App) {
+    let amount_input = cx.new(|cx| InputState::new(window, cx).placeholder("Amount (sats)"));
+    let token_input = cx.new(|cx| InputState::new(window, cx).placeholder("cashu…"));
+
+    let create_invoice: SubmitFn = {
+        let wallet = WalletRegistry::global(cx);
+        let input = amount_input.clone();
+        Rc::new(move |_, window, cx| {
+            let Some(amount) = parse_amount(&input, cx) else {
+                window.push_notification(Notification::error("Enter an amount in sats"), cx);
+                return false;
+            };
+
+            wallet.update(cx, |registry, cx| {
+                registry.create_mint_quote(amount, cx);
+            });
+
+            true
+        })
+    };
+
+    let redeem: SubmitFn = {
+        let wallet = WalletRegistry::global(cx);
+        let input = token_input.clone();
+        Rc::new(move |_, window, cx| {
+            let token = input.read(cx).value().trim().to_string();
+
+            if token.is_empty() {
+                window.push_notification(Notification::error("Paste a cashu token"), cx);
+                return false;
+            }
+
+            wallet.update(cx, |registry, cx| {
+                registry.receive_token(token, cx);
+            });
+
+            true
+        })
+    };
+
+    window.open_dialog(cx, move |this, _window, _cx| {
+        this.width(px(420.))
+            .title("Receive")
+            .on_ok({
+                let token_input = token_input.clone();
+                let create_invoice = create_invoice.clone();
+                let redeem = redeem.clone();
+                move |_event, window, cx| {
+                    if !token_input.read(cx).value().trim().is_empty() {
+                        redeem(_event, window, cx)
+                    } else {
+                        create_invoice(_event, window, cx)
+                    }
+                }
+            })
+            .child(
+                v_flex()
+                    .gap_3()
+                    .child(
+                        v_flex()
+                            .gap_1p5()
+                            .child(div().text_xs().font_semibold().child("Lightning invoice:"))
+                            .child(
+                                h_flex()
+                                    .gap_1()
+                                    .w_full()
+                                    .child(Input::new(&amount_input).cleanable(true))
+                                    .child(
+                                        Button::new("invoice")
+                                            .label("Invoice")
+                                            .secondary()
+                                            .w_24()
+                                            .on_click({
+                                                let create_invoice = create_invoice.clone();
+                                                move |event, window, cx| {
+                                                    if create_invoice(event, window, cx) {
+                                                        window.close_dialog(cx);
+                                                    }
+                                                }
+                                            }),
+                                    ),
+                            ),
+                    )
+                    .child(Separator::horizontal())
+                    .child(
+                        v_flex()
+                            .gap_1p5()
+                            .child(div().text_xs().font_semibold().child("Cashu token:"))
+                            .child(
+                                h_flex()
+                                    .gap_1()
+                                    .w_full()
+                                    .child(Input::new(&token_input).cleanable(true))
+                                    .child(
+                                        Button::new("redeem")
+                                            .label("Redeem")
+                                            .secondary()
+                                            .w_24()
+                                            .on_click({
+                                                let redeem = redeem.clone();
+                                                move |event, window, cx| {
+                                                    if redeem(event, window, cx) {
+                                                        window.close_dialog(cx);
+                                                    }
+                                                }
+                                            }),
+                                    ),
+                            ),
+                    ),
+            )
+    });
+}
+
+fn parse_amount(input: &Entity<InputState>, cx: &App) -> Option<u64> {
+    match input.read(cx).value().trim().parse::<u64>() {
+        Ok(amount) if amount > 0 => Some(amount),
+        _ => None,
+    }
+}
+
+impl gpui_kit::component::dock::BasePanel for WalletPanel {
+    fn panel_name(&self) -> &'static str {
+        "Wallet"
+    }
+}
+
+impl Panel for WalletPanel {
+    fn title(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        h_flex()
+            .gap_1p5()
+            .child(
+                Icon::new(IconName::Wallet)
+                    .small()
+                    .text_color(cx.theme().muted_foreground),
+            )
+            .child(self.name.clone())
+            .into_any_element()
+    }
+}
+
+impl EventEmitter<PanelEvent> for WalletPanel {}
+
+impl Focusable for WalletPanel {
+    fn focus_handle(&self, _: &App) -> FocusHandle {
+        self.focus_handle.clone()
+    }
+}
+
+impl Render for WalletPanel {
+    fn render(&mut self, _window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
+        let history = WalletRegistry::global(cx).read(cx).history().to_vec();
+
+        v_flex()
+            .size_full()
+            .p_3()
+            .gap_4()
+            .text_xs()
+            .child(self.render_balance(cx))
+            .child(self.render_actions())
+            .child(
+                v_flex()
+                    .gap_2()
+                    .child(
+                        div()
+                            .text_xs()
+                            .font_semibold()
+                            .text_color(cx.theme().muted_foreground)
+                            .child("History"),
+                    )
+                    .child(self.render_history(history, cx)),
+            )
+    }
+}

crates/workspace/Cargo.toml

@@ -9,11 +9,11 @@ ui = { path = "../ui" }
 gpui-kit.workspace = true
 common = { path = "../common" }
 state = { path = "../state" }
+nip29 = { path = "../nip29" }
+nip29_ui = { path = "../nip29_ui" }
 nip4e = { path = "../nip4e" }
 chat = { path = "../chat" }
 chat_ui = { path = "../chat_ui" }
-nip29 = { path = "../nip29" }
-nip29_ui = { path = "../nip29_ui" }
 settings = { path = "../settings" }
 speech = { path = "../speech" }
 person = { path = "../person" }
@@ -30,3 +30,7 @@ serde.workspace = true
 log.workspace = true
 rand.workspace = true
 smallvec.workspace = true
+
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+nip60 = { path = "../nip60" }
+nip60_ui = { path = "../nip60_ui" }

crates/workspace/src/dialogs/join_group.rs

@@ -1,11 +1,11 @@
+use std::rc::Rc;
+
+use gpui::{App, AppContext, ClickEvent, ParentElement, Styled, Window, px};
 use gpui_kit::assets::IconName;
 use gpui_kit::component::button::{Button, ButtonVariants};
 use gpui_kit::component::input::{Input, InputState};
 use gpui_kit::component::notification::Notification;
 use gpui_kit::component::{WindowExt, h_flex, v_flex};
-use std::rc::Rc;
-
-use gpui::{App, AppContext, ClickEvent, ParentElement, Styled, Window, px};
 use nip29::{GroupReference, GroupsRegistry};
 
 type SubmitFn = Rc<dyn Fn(&ClickEvent, &mut Window, &mut App) -> bool>;

crates/workspace/src/dialogs/settings.rs

@@ -41,6 +41,8 @@ pub struct Preferences {
     radius_input: Entity<InputState>,
     radius_lg_input: Entity<InputState>,
     #[cfg(not(target_arch = "wasm32"))]
+    mint_input: Entity<InputState>,
+    #[cfg(not(target_arch = "wasm32"))]
     _speech_poll: Task<()>,
     /// Keeps the control subscriptions alive while the dialog is open
     _subscriptions: Vec<Subscription>,
@@ -90,6 +92,9 @@ impl Preferences {
                 .max(RADIUS_RANGE.1 as f64)
         });
 
+        #[cfg(not(target_arch = "wasm32"))]
+        let mint_input = cx.new(|cx| InputState::new(window, cx).placeholder("https://mint…"));
+
         let subscriptions = vec![
             Self::wire_number_input(&font_size_input, FONT_SIZE_RANGE, cx, |value, cx| {
                 if let Some(font_size) = value {
@@ -140,6 +145,8 @@ impl Preferences {
             radius_input,
             radius_lg_input,
             #[cfg(not(target_arch = "wasm32"))]
+            mint_input,
+            #[cfg(not(target_arch = "wasm32"))]
             _speech_poll,
             _subscriptions: subscriptions,
         }
@@ -185,6 +192,56 @@ impl Preferences {
         }
     }
 
+    /// Create the NIP-60 wallet or add a mint to it
+    #[cfg(not(target_arch = "wasm32"))]
+    fn setup_mint(&mut self, window: &mut Window, cx: &mut Context<Self>) {
+        let mint = self.mint_input.read(cx).value().trim().to_string();
+        if mint.is_empty() {
+            window.push_notification(Notification::error("Enter a mint URL"), cx);
+            return;
+        }
+
+        nip60::WalletRegistry::global(cx).update(cx, |registry, cx| {
+            registry.setup(mint, cx);
+        });
+    }
+
+    /// The NIP-60 wallet block; absent from the web build
+    fn render_wallet(
+        &mut self,
+        #[cfg_attr(target_arch = "wasm32", allow(unused_variables))] cx: &mut Context<Self>,
+    ) -> AnyElement {
+        #[cfg(target_arch = "wasm32")]
+        {
+            return div().into_any_element();
+        }
+
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            const WALLET: &str = "Cashu mint for your NIP-60 wallet. Set up creates the wallet, Add extends it with another mint.";
+            let has_wallet = nip60::WalletRegistry::global(cx).read(cx).has_wallet();
+
+            settings_block(
+                "Wallet",
+                WALLET,
+                h_flex()
+                    .gap_1()
+                    .child(div().flex_1().child(Input::new(&self.mint_input)))
+                    .child(
+                        Button::new("setup-mint")
+                            .label(if has_wallet { "Add" } else { "Set up" })
+                            .ghost()
+                            .size_8()
+                            .on_click(cx.listener(move |this, _ev, window, cx| {
+                                this.setup_mint(window, cx);
+                            })),
+                    ),
+                cx,
+            )
+            .into_any_element()
+        }
+    }
+
     /// Set the appearance mode (system, light or dark)
     fn set_appearance_mode(mode: AppearanceMode, cx: &mut App) {
         AppSettings::update_appearance_mode(mode, cx);
@@ -546,5 +603,7 @@ impl Render for Preferences {
                     ),
                 cx,
             ))
+            .child(Separator::horizontal())
+            .child(self.render_wallet(cx))
     }
 }

crates/workspace/src/lib.rs

@@ -61,6 +61,7 @@ enum Command {
     ShowContactList,
     ShowInbox,
     ShowBrowse,
+    ShowWallet,
     NewChat,
     NewGroup,
     JoinGroup,
@@ -196,6 +197,30 @@ impl Workspace {
             }),
         );
 
+        #[cfg(not(target_arch = "wasm32"))]
+        {
+            let wallet = ::nip60::WalletRegistry::global(cx);
+
+            subscriptions.push(cx.subscribe_in(
+                &wallet,
+                window,
+                |_this, _wallet, event, window, cx| match event {
+                    ::nip60::WalletEvent::Error(error) => {
+                        window.push_notification(Notification::error(error.clone()), cx);
+                    }
+                    ::nip60::WalletEvent::TokenCreated(_) => {
+                        window.push_notification(
+                            Notification::new()
+                                .message("Cashu token created, copy it from the wallet panel")
+                                .with_type(NotificationType::Success),
+                            cx,
+                        );
+                    }
+                    ::nip60::WalletEvent::Updated => {}
+                },
+            ));
+        }
+
         App::on_action(cx, {
             let workspace = workspace.clone();
             move |action, cx| {
@@ -307,6 +332,13 @@ impl Workspace {
                 let panel = browse::init(self.dock.downgrade(), window, cx);
                 self.add_panel_to_dock(panel, DockPlacement::Center, window, cx);
             }
+            Command::ShowWallet => {
+                #[cfg(not(target_arch = "wasm32"))]
+                {
+                    let panel = nip60_ui::wallet::init(window, cx);
+                    self.add_panel_to_dock(panel, DockPlacement::Center, window, cx);
+                }
+            }
             Command::NewChat => {
                 new_chat::open(self.dock.downgrade(), window, cx);
             }

crates/workspace/src/sidebar/list.rs

@@ -39,7 +39,6 @@ impl Sidebar {
         let requests_open = self.requests_open;
         let contacts_open = self.contacts_open && !requests_open;
         let rows = Rc::new(self.rows_for(cx));
-
         // Whether to show the create button for the contact picker
         let create_button = contacts_open && !self.selected_contacts.is_empty();
 
@@ -60,12 +59,25 @@ impl Sidebar {
             .flex_1()
             .min_h_0()
             .relative()
+            .border_l_1()
+            .border_color(cx.theme().sidebar_border)
             .child(
                 v_flex()
                     .px_2()
                     .gap_1()
                     .items_start()
                     .justify_start()
+                    .when(cfg!(not(target_arch = "wasm32")), |this| {
+                        this.child(
+                            Nav::new("wallet")
+                                .prefix(Icon::new(gpui_kit::assets::IconName::Wallet).small())
+                                .label("Wallet")
+                                .text_sm()
+                                .on_click(|_, window, cx| {
+                                    window.dispatch_action(Box::new(crate::Command::ShowWallet), cx)
+                                }),
+                        )
+                    })
                     .child(
                         Nav::new("browse")
                             .prefix(Icon::new(IconName::Compass).small())