diff --git a/src/Directory.Build.props b/src/Directory.Build.props
index e869350d2..37442164d 100644
--- a/src/Directory.Build.props
+++ b/src/Directory.Build.props
@@ -11,6 +11,13 @@
     <!-- Audit all package dependencies (direct + transitive) for known CVEs during restore.
          Defaults to "direct" in the SDK; "all" provides broader security coverage. -->
     <NuGetAuditMode>all</NuGetAuditMode>
+
+    <!-- Treat compiler warnings as errors across all source projects.
+         Keeps the warning count at zero and prevents silent warning accumulation
+         that is later expensive to clean up. Individual projects may suppress a
+         specific warning via <NoWarn> only when the warning is intentional and
+         the suppression is documented. -->
+    <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
   </PropertyGroup>
 
 </Project>
diff --git a/src/OpenClaw.Shared/OpenClaw.Shared.csproj b/src/OpenClaw.Shared/OpenClaw.Shared.csproj
index 82b057ea2..cead66ca8 100644
--- a/src/OpenClaw.Shared/OpenClaw.Shared.csproj
+++ b/src/OpenClaw.Shared/OpenClaw.Shared.csproj
@@ -5,6 +5,12 @@
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <RootNamespace>OpenClaw.Shared</RootNamespace>
+    <!-- CS8524: switch expression on an enum without a _ arm — intentional in
+         ExecApprovalsCoordinator so the compiler flags any new enum member that
+         is added without a corresponding case.  The remaining int-cast space
+         (e.g. (ExecApprovalPromptOutcome)4) is an acceptable gap given that all
+         callers produce only named values. -->
+    <NoWarn>$(NoWarn);CS8524</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>