diff --git a/src/plugins/asset.ts b/src/plugins/asset.ts
index de2b3f6..db5b935 100644
--- a/src/plugins/asset.ts
+++ b/src/plugins/asset.ts
@@ -173,7 +173,7 @@ export default function assetPlugin(): Plugin {
       if (s) {
         return {
           code: s.toString(),
-          map: sourcemap ? s.generateMap({ hires: true }) : null
+          map: sourcemap ? s.generateMap({ hires: 'boundary' }) : null
         }
       } else {
         return null
diff --git a/src/plugins/bytecode.ts b/src/plugins/bytecode.ts
index 88ecf2e..d740eb5 100644
--- a/src/plugins/bytecode.ts
+++ b/src/plugins/bytecode.ts
@@ -222,7 +222,7 @@ export function bytecodePlugin(options: BytecodeOptions = {}): Plugin | null {
       if (s) {
         return {
           code: s.toString(),
-          map: config.build.sourcemap ? s.generateMap({ hires: true }) : null
+          map: config.build.sourcemap ? s.generateMap({ hires: 'boundary' }) : null
         }
       }
     },
diff --git a/src/plugins/esm.ts b/src/plugins/esm.ts
index 887909f..88fa6de 100644
--- a/src/plugins/esm.ts
+++ b/src/plugins/esm.ts
@@ -56,7 +56,7 @@ export default function esmShimPlugin(): Plugin {
         s.appendRight(indexToAppend, CJSShim)
         return {
           code: s.toString(),
-          map: sourcemap ? s.generateMap({ hires: true }) : null
+          map: sourcemap ? s.generateMap({ hires: 'boundary' }) : null
         }
       }
 
diff --git a/src/plugins/worker.ts b/src/plugins/worker.ts
index 257ed00..b887fa0 100644
--- a/src/plugins/worker.ts
+++ b/src/plugins/worker.ts
@@ -55,7 +55,7 @@ export default function workerPlugin(): Plugin {
 
         return {
           code: s.toString(),
-          map: sourcemap ? s.generateMap({ hires: true }) : null
+          map: sourcemap ? s.generateMap({ hires: 'boundary' }) : null
         }
       }