fix(wallets): preserve USDT transaction history precision

src/app/wallets/get-transactions-for-wallet.ts

@@ -77,7 +77,7 @@ export const toWalletTransactions = (ibexResp: GResponse200): IbexTransaction[]
     const baseTrx: BaseWalletTransaction = {
       walletId: (trx.accountId || "") as WalletId, 
       settlementAmount: toSettlementAmount(trx.amount, trx.transactionTypeId, currency),
-      settlementFee: asCurrency(trx.networkFee, currency),
+      settlementFee: toSettlementMinorUnit(trx.networkFee, currency),
       settlementCurrency: currency, 
       settlementDisplayAmount: `${trx.amount}`, 
       settlementDisplayFee: `${trx.networkFee}`, 
@@ -118,24 +118,49 @@ export const toWalletTransactions = (ibexResp: GResponse200): IbexTransaction[]
   })
 }
 
-const asCurrency = (amount: number | undefined, currency: WalletCurrency): Satoshis | UsdCents => {
-  return currency === "USD" ? amount as UsdCents : amount as Satoshis
+type SettlementMinorUnitAmount = Satoshis | UsdCents | UsdtMicros
+
+const toUsdtMicros = (amount: number): UsdtMicros => {
+  const usdtAmount = USDTAmount.fromNumber(amount.toString())
+  if (usdtAmount instanceof Error) {
+    baseLogger.error({ err: usdtAmount, amount }, "Failed to parse IBEX USDT amount")
+    return 0 as UsdtMicros
+  }
+  return Number(usdtAmount.asSmallestUnits()) as UsdtMicros
+}
+
+const zeroSettlementMinorUnit = (
+  currency: WalletCurrency,
+): SettlementMinorUnitAmount => {
+  if (currency === WalletCurrency.Usd) return 0 as UsdCents
+  if (currency === WalletCurrency.Usdt) return 0 as UsdtMicros
+  return 0 as Satoshis
+}
+
+const toSettlementMinorUnit = (
+  amount: number | undefined,
+  currency: WalletCurrency,
+): SettlementMinorUnitAmount => {
+  if (amount === undefined) return zeroSettlementMinorUnit(currency)
+  if (currency === WalletCurrency.Usd) return amount as UsdCents
+  if (currency === WalletCurrency.Usdt) return toUsdtMicros(amount)
+  return amount as Satoshis
 }
 
 const toSettlementAmount = (
   ibexAmount: number | undefined, 
   transactionTypeId: number | undefined, 
   currency: WalletCurrency
-): Satoshis | UsdCents => {
+): SettlementMinorUnitAmount => {
   if (ibexAmount === undefined) {
     baseLogger.warn("Ibex did not return transaction amount")
-    return asCurrency(ibexAmount, currency) 
+    return toSettlementMinorUnit(ibexAmount, currency)
   }
   // When sending, make negative
   const amt = (transactionTypeId === 2 || transactionTypeId === 4) 
     ? -1 * ibexAmount 
     : ibexAmount
-  return asCurrency(amt, currency)
+  return toSettlementMinorUnit(amt, currency)
 }
 
 enum SortOrder {

src/domain/shared/index.types.d.ts

@@ -49,6 +49,7 @@ type WalletDescriptor<T extends WalletCurrency> = PartialWalletDescriptor<T> & {
 
 type BtcPaymentAmount = PaymentAmount<"BTC">
 type UsdPaymentAmount = PaymentAmount<"USD">
+type UsdtMicros = number & { readonly brand: unique symbol }
 
 type RequireField<T, K extends keyof T> = T & Required<Pick<T, K>>
 

src/domain/wallets/index.types.d.ts

@@ -71,8 +71,8 @@ type PartialBaseWalletTransaction = {
 
 type BaseWalletTransaction = {
   readonly walletId: WalletId | undefined
-  readonly settlementAmount: Satoshis | UsdCents
-  readonly settlementFee: Satoshis | UsdCents
+  readonly settlementAmount: Satoshis | UsdCents | UsdtMicros
+  readonly settlementFee: Satoshis | UsdCents | UsdtMicros
   readonly settlementCurrency: WalletCurrency
 
   readonly settlementDisplayAmount: DisplayCurrencyMajorAmount

test/flash/unit/app/wallets/get-transactions-for-wallet.spec.ts

@@ -12,6 +12,7 @@ import {
 import { WalletCurrency } from "@domain/shared"
 import { WalletType } from "@domain/wallets"
 import Ibex from "@services/ibex/client"
+import { baseLogger } from "@services/logger"
 import { GResponse200 } from "ibex-client"
 
 const accountId = "account-id" as AccountId
@@ -28,20 +29,108 @@ const wallet = ({ id, currency }: { id: string; currency: WalletCurrency }): Wal
   }) as Wallet
 
 describe("toWalletTransactions", () => {
-  it("maps IBEX USDT currency id to USDT wallet currency", () => {
+  it("maps IBEX USDT currency id to USDT wallet currency with integer micros", () => {
+    const transactions = toWalletTransactions([
+      {
+        id: "trx-id-1",
+        accountId: "wallet-id",
+        amount: 0.17531,
+        currencyId: 29,
+        transactionTypeId: 1,
+        createdAt: "2026-05-13T00:00:00.000Z",
+      },
+      {
+        id: "trx-id-2",
+        accountId: "wallet-id",
+        amount: 9.824690376349,
+        currencyId: 29,
+        transactionTypeId: 1,
+        createdAt: "2026-05-13T00:00:00.000Z",
+      },
+    ] as GResponse200)
+
+    expect(transactions).toHaveLength(2)
+    expect(transactions[0].settlementCurrency).toBe(WalletCurrency.Usdt)
+    expect(transactions[0].settlementAmount).toBe(175_310)
+    expect(transactions[1].settlementAmount).toBe(9_824_690)
+    expect(
+      transactions.reduce((sum, transaction) => sum + transaction.settlementAmount, 0),
+    ).toBe(10_000_000)
+  })
+
+  it("maps IBEX USDT send amounts to negative integer micros", () => {
+    const [transaction] = toWalletTransactions([
+      {
+        id: "trx-id",
+        accountId: "wallet-id",
+        amount: 0.5,
+        networkFee: 0.000001,
+        currencyId: 29,
+        transactionTypeId: 2,
+        createdAt: "2026-05-13T00:00:00.000Z",
+      },
+    ] as GResponse200)
+
+    expect(transaction.settlementCurrency).toBe(WalletCurrency.Usdt)
+    expect(transaction.settlementAmount).toBe(-500_000)
+    expect(transaction.settlementFee).toBe(1)
+  })
+
+  it("defaults omitted IBEX USDT amount and network fee to zero micros", () => {
     const [transaction] = toWalletTransactions([
       {
         id: "trx-id",
         accountId: "wallet-id",
-        amount: 19446,
         currencyId: 29,
         transactionTypeId: 1,
         createdAt: "2026-05-13T00:00:00.000Z",
       },
     ] as GResponse200)
 
     expect(transaction.settlementCurrency).toBe(WalletCurrency.Usdt)
-    expect(transaction.settlementAmount).toBe(19446)
+    expect(transaction.settlementAmount).toBe(0)
+    expect(transaction.settlementFee).toBe(0)
+  })
+
+  it("logs USDT conversion errors with error details", () => {
+    const errorSpy = jest.spyOn(baseLogger, "error").mockImplementation()
+
+    const [transaction] = toWalletTransactions([
+      {
+        id: "trx-id",
+        accountId: "wallet-id",
+        amount: Number.NaN,
+        currencyId: 29,
+        transactionTypeId: 1,
+        createdAt: "2026-05-13T00:00:00.000Z",
+      },
+    ] as GResponse200)
+
+    expect(transaction.settlementAmount).toBe(0)
+    expect(errorSpy).toHaveBeenCalledWith(
+      expect.objectContaining({ err: expect.any(Error), amount: expect.any(Number) }),
+      "Failed to parse IBEX USDT amount",
+    )
+
+    errorSpy.mockRestore()
+  })
+
+  it("keeps IBEX USD amounts in integer cents", () => {
+    const [transaction] = toWalletTransactions([
+      {
+        id: "trx-id",
+        accountId: "wallet-id",
+        amount: 500,
+        networkFee: 12,
+        currencyId: 3,
+        transactionTypeId: 1,
+        createdAt: "2026-05-13T00:00:00.000Z",
+      },
+    ] as GResponse200)
+
+    expect(transaction.settlementCurrency).toBe(WalletCurrency.Usd)
+    expect(transaction.settlementAmount).toBe(500)
+    expect(transaction.settlementFee).toBe(12)
   })
 
   it("does not silently classify unknown IBEX currency ids as BTC", () => {