diff --git a/pkgs/native_toolchain_c/lib/src/cbuilder/cbuilder.dart b/pkgs/native_toolchain_c/lib/src/cbuilder/cbuilder.dart
index c3a97f8b7..62ec22015 100644
--- a/pkgs/native_toolchain_c/lib/src/cbuilder/cbuilder.dart
+++ b/pkgs/native_toolchain_c/lib/src/cbuilder/cbuilder.dart
@@ -68,7 +68,7 @@ class CBuilder extends CTool implements Builder {
     super.language = Language.c,
     super.cppLinkStdLib,
     super.linkModePreference,
-    super.optimizationLevel = OptimizationLevel.oS,
+    super.optimizationLevel = OptimizationLevel.o3,
   }) : super(type: OutputType.library);
 
   CBuilder.executable({
@@ -89,7 +89,7 @@ class CBuilder extends CTool implements Builder {
     super.std,
     super.language = Language.c,
     super.cppLinkStdLib,
-    super.optimizationLevel = OptimizationLevel.oS,
+    super.optimizationLevel = OptimizationLevel.o3,
   }) : super(
           type: OutputType.executable,
           assetName: null,
diff --git a/pkgs/native_toolchain_c/lib/src/cbuilder/clinker.dart b/pkgs/native_toolchain_c/lib/src/cbuilder/clinker.dart
index 9a10f504a..b79174967 100644
--- a/pkgs/native_toolchain_c/lib/src/cbuilder/clinker.dart
+++ b/pkgs/native_toolchain_c/lib/src/cbuilder/clinker.dart
@@ -37,7 +37,7 @@ class CLinker extends CTool implements Linker {
     super.language = Language.c,
     super.cppLinkStdLib,
     super.linkModePreference,
-    super.optimizationLevel = OptimizationLevel.oS,
+    super.optimizationLevel = OptimizationLevel.o3,
   }) : super(type: OutputType.library);
 
   /// Runs the C Linker with on this C build spec.