diff --git a/src/modules/wallet/services/WalletService.ts b/src/modules/wallet/services/WalletService.ts
index 0448e64..9ef9d84 100644
--- a/src/modules/wallet/services/WalletService.ts
+++ b/src/modules/wallet/services/WalletService.ts
@@ -4,6 +4,9 @@ import { injectService, SERVICE_TOKENS } from '@/core/di-container'
 import { config } from '@/lib/config'
 import { decode as decodeBolt11 } from 'light-bolt11-decoder'
 
+/** The `amount` member of light-bolt11-decoder's `Section` union. */
+type AmountSection = { name: 'amount'; letters: string; value: string }
+
 export interface PayLink {
   id: string
   wallet: string
@@ -344,7 +347,14 @@ export default class WalletService extends BaseService {
   private getInvoiceAmountMsat(bolt11: string): number | null {
     try {
       const decoded = decodeBolt11(bolt11)
-      const section = decoded.sections.find((s: any) => s.name === 'amount')
+      // `sections` is a discriminated union, and not every member carries a
+      // `value` — the "checksum" member has only `letters`. Narrow with a
+      // type predicate so the compiler knows which member we are reading;
+      // an `(s: any)` callback is not a type guard, so `find` still returned
+      // the whole union and `.value` failed to resolve under `vue-tsc -b`.
+      const section = decoded.sections.find(
+        (s): s is AmountSection => s.name === 'amount'
+      )
       if (!section || section.value === undefined || section.value === null) return 0
       return Number(section.value)
     } catch (error) {