feat: add multi-account support for batch builder

CHANGELOG.md

@@ -10,7 +10,7 @@
 ### Enhancements
 
 * [FEATURE][web,react] AggLayer bridge-out (B2AGG) note support. `client.transactions.bridge({ account, bridgeAccount, token, amount, destinationNetwork, destinationAddress })` bridges a fungible asset out to another network — emitting a single public B2AGG (Bridge-to-AggLayer) note that the bridge account consumes, burning the asset so it can be claimed at the destination Ethereum address on the AggLayer-assigned `destinationNetwork`. The lower-level builders are also exposed: `Note.createB2AggNote(sender, bridgeAccount, assets, destinationNetwork, destinationAddress)` and `client.newB2AggTransactionRequest(...)`. A new `EthAddress` class carries the 20-byte destination address (`EthAddress.fromHex("0x…")` / `EthAddress.fromBytes(bytes)`, with `toHex()` / `toBytes()`). The `@miden-sdk/react` `useBridge()` hook wraps the build-and-submit flow: `bridge({ from, bridgeAccount, assetId, amount, destinationNetwork, destinationAddress })`. Builds on the `miden-agglayer` re-export already present in the bundled `miden-client` — no new dependency. (closes [#173](https://github.com/0xMiden/web-sdk/issues/173))
-* [FEATURE][web] Added `client.transactions.batch({ account, operations })` to `MidenClient` for atomic multi-tx batches against a single account. Operations are discriminated by `kind` (`"send" | "mint" | "consume" | "swap" | "execute" | "custom"`) and reuse the same options shape as their singular counterparts. Returns `{ blockNumber }`. Companion `submitBatch(account, requests, options?)` is the lower-level escape hatch for pre-built `TransactionRequest`s. Wraps the underlying WASM `submitNewTransactionBatch` so consumers don't have to call `.serialize()` themselves. ([web-sdk#31](https://github.com/0xMiden/web-sdk/pull/31), client [#2109](https://github.com/0xMiden/miden-client/pull/2109))
+* [FEATURE][web] Added `client.transactions.batch({ operations })` to `MidenClient` for atomic multi-tx batches across one or more local accounts. Each operation specifies its executing `account`; a batch may mix operations across any combination of tracked accounts, and a later transaction may consume a note produced by an earlier one (cross-account in-batch note flow supported). Operations are discriminated by `kind` (`"send" | "mint" | "consume" | "swap" | "execute" | "custom"`) and reuse the same options shape as their singular counterparts. Returns `{ blockNumber }`. Companion `submitBatch(items, options?)` takes an array of `{ account, request }` pairs and is the lower-level escape hatch for pre-built `TransactionRequest`s. Wraps the underlying WASM `submitNewTransactionBatch(items: BatchItem[])`, where each `BatchItem` is a `(AccountId, TransactionRequest)` pair built via `new BatchItem(accountId, request)`. ([web-sdk#31](https://github.com/0xMiden/web-sdk/pull/31), client [#2109](https://github.com/0xMiden/miden-client/pull/2109), [#2177](https://github.com/0xMiden/miden-client/pull/2177))
 
 ## 0.15.3 (2026-06-25)
 

crates/idxdb-store/src/account/mod.rs

@@ -1,4 +1,4 @@
-use alloc::collections::BTreeMap;
+use alloc::collections::{BTreeMap, BTreeSet};
 use alloc::string::{String, ToString};
 use alloc::vec::Vec;
 
@@ -343,8 +343,7 @@ impl IdxdbStore {
                 }
             },
             AccountStorageFilter::SlotNames(names) => {
-                let wanted: alloc::collections::BTreeSet<&str> =
-                    names.iter().map(StorageSlotName::as_str).collect();
+                let wanted: BTreeSet<&str> = names.iter().map(StorageSlotName::as_str).collect();
                 account_storage_idxdb
                     .into_iter()
                     .filter(|s| wanted.contains(s.slot_name.as_str()))

crates/idxdb-store/src/transaction/mod.rs

@@ -326,8 +326,9 @@ impl IdxdbStore {
 
         // Simulates read-writes across batch transactions, since nothing is persisted to
         // IndexedDB until the single Dexie transaction at the end.
-        let mut vault_overlay: BTreeMap<AssetVaultKey, Option<Asset>> = BTreeMap::new();
-        let mut map_roots_overlay: BTreeMap<StorageSlotName, Word> = BTreeMap::new();
+        let mut vault_overlay: BTreeMap<(AccountId, AssetVaultKey), Option<Asset>> =
+            BTreeMap::new();
+        let mut map_roots_overlay: BTreeMap<(AccountId, StorageSlotName), Word> = BTreeMap::new();
 
         for update in &tx_updates {
             let (payload, account_id) = self
@@ -377,8 +378,8 @@ impl IdxdbStore {
     async fn prepare_update_for_batch(
         &self,
         update: &TransactionStoreUpdate,
-        vault_overlay: &mut BTreeMap<AssetVaultKey, Option<Asset>>,
-        map_roots_overlay: &mut BTreeMap<StorageSlotName, Word>,
+        vault_overlay: &mut BTreeMap<(AccountId, AssetVaultKey), Option<Asset>>,
+        map_roots_overlay: &mut BTreeMap<(AccountId, StorageSlotName), Word>,
     ) -> Result<(BatchUpdatePayload, AccountId), StoreError> {
         let executed_tx = update.executed_transaction();
         let delta = executed_tx.account_delta();
@@ -422,14 +423,14 @@ impl IdxdbStore {
 
             // Seed overlays with the new full account state so subsequent non-full-state
             // preparations in the same batch see post-this-tx values.
-            vault_overlay.clear();
+            vault_overlay.retain(|(acc, _), _| *acc != account_id);
             for asset in account.vault().assets() {
-                vault_overlay.insert(asset.vault_key(), Some(asset));
+                vault_overlay.insert((account_id, asset.vault_key()), Some(asset));
             }
-            map_roots_overlay.clear();
+            map_roots_overlay.retain(|(acc, _), _| *acc != account_id);
             for slot in account.storage().slots() {
                 if let StorageSlotContent::Map(map) = slot.content() {
-                    map_roots_overlay.insert(slot.name().clone(), map.root());
+                    map_roots_overlay.insert((account_id, slot.name().clone()), map.root());
                 }
             }
 
@@ -474,7 +475,7 @@ impl IdxdbStore {
             let mut old_vault_assets: Vec<Asset> = Vec::new();
             let mut vault_keys_to_fetch: Vec<String> = Vec::new();
             for (vault_key, _) in delta.vault().fungible().iter() {
-                match vault_overlay.get(vault_key) {
+                match vault_overlay.get(&(account_id, *vault_key)) {
                     Some(Some(asset)) => old_vault_assets.push(*asset),
                     Some(None) => { /* key was removed earlier in the batch; treat as empty */ },
                     None => vault_keys_to_fetch.push(vault_key.to_string()),
@@ -488,7 +489,7 @@ impl IdxdbStore {
             let mut old_map_roots: BTreeMap<StorageSlotName, Word> = BTreeMap::new();
             let mut map_slot_names_to_fetch: Vec<String> = Vec::new();
             for (slot_name, _) in delta.storage().maps() {
-                if let Some(root) = map_roots_overlay.get(slot_name) {
+                if let Some(root) = map_roots_overlay.get(&(account_id, slot_name.clone())) {
                     old_map_roots.insert(slot_name.clone(), *root);
                 } else {
                     map_slot_names_to_fetch.push(slot_name.to_string());
@@ -547,16 +548,16 @@ impl IdxdbStore {
                 smt_forest.stage_roots(account_id, final_roots);
 
                 // Propagate this tx's post-state into the overlays so subsequent preparations
-                // in the same batch see these updates.
+                // against this same account in the batch see these updates.
                 for asset in &updated_assets {
-                    vault_overlay.insert(asset.vault_key(), Some(*asset));
+                    vault_overlay.insert((account_id, asset.vault_key()), Some(*asset));
                 }
                 for vault_key in &removed_vault_keys {
-                    vault_overlay.insert(*vault_key, None);
+                    vault_overlay.insert((account_id, *vault_key), None);
                 }
                 for (slot_name, (new_root, slot_type)) in &updated_storage_slots {
                     if *slot_type == StorageSlotType::Map {
-                        map_roots_overlay.insert(slot_name.clone(), *new_root);
+                        map_roots_overlay.insert((account_id, slot_name.clone()), *new_root);
                     }
                 }
 

crates/web-client/README.md

@@ -454,35 +454,32 @@ console.log(`Balance: ${balance}`);
 
 ### Batch Operations
 
-Submit multiple operations against a single account as one atomic batch — every transaction in the batch lands together or none does. Each operation builds its own `TransactionRequest` internally; you don't have to assemble or serialize them yourself.
+Submit multiple operations across one or more local accounts as one atomic batch — every transaction in the batch lands together or none does. Each operation builds its own `TransactionRequest` internally; you don't have to assemble or serialize them yourself.
 
 ```typescript
 const { blockNumber } = await client.transactions.batch({
-  account: wallet,
   operations: [
-    { kind: "send", to: alice, token: dagToken, amount: 50n, type: "public" },
-    { kind: "send", to: bob,   token: dagToken, amount: 30n, type: "public" },
-    { kind: "consume", notes: pendingNotes },
+    { kind: "send", account: alice, to: bob, token: dagToken, amount: 50n, type: "public" },
+    { kind: "send", account: alice, to: carol, token: dagToken, amount: 30n, type: "public" },
+    { kind: "consume", account: bob, notes: pendingNotes },
   ],
   waitForConfirmation: true,
 });
 console.log(`Batch landed in block ${blockNumber}`);
 ```
 
-Operations are discriminated by `kind`: `"send"`, `"mint"`, `"consume"`, `"swap"`, `"execute"`, and `"custom"` (escape hatch for a pre-built `TransactionRequest`). The shape of each operation mirrors the singular options object (`SendOptions`, `MintOptions`, …) minus the `account` field, which is set once at the batch level.
-
-V1 supports only same-account batches — every operation must execute against the `account` passed at the top level. Mixing accounts in one batch is not supported.
+Operations are discriminated by `kind`: `"send"`, `"mint"`, `"consume"`, `"swap"`, `"execute"`, and `"custom"` (escape hatch for a pre-built `TransactionRequest`). Each operation specifies its executing `account`; a batch may mix any combination of tracked local accounts, and a later transaction may consume a note produced by an earlier one in the same batch.
 
-For callers that already hold pre-built `TransactionRequest`s, `submitBatch` skips the high-level builders:
+For callers that already hold pre-built `TransactionRequest`s, `submitBatch` skips the high-level builders. Pass an array of `{ account, request }` pairs:
 
 ```typescript
-const { blockNumber } = await client.transactions.submitBatch(wallet, [
-  request1,
-  request2,
+const { blockNumber } = await client.transactions.submitBatch([
+  { account: alice, request: request1 },
+  { account: bob, request: request2 },
 ]);
 ```
 
-The V1 batch primitive returns only the block number — there are no per-tx ids in the result. `waitForConfirmation` polls local sync height until it reaches `blockNumber` (rather than per-tx polling like singular `send` / `consume`).
+The batch primitive returns only the block number — there are no per-tx ids in the result. `waitForConfirmation` polls local sync height until it reaches `blockNumber` (rather than per-tx polling like singular `send` / `consume`).
 
 ### Partial-Swap (PSWAP) Orders