diff --git a/Lib9c/Lib9c.csproj b/Lib9c/Lib9c.csproj
index 8defb1aac9..b867a86a58 100644
--- a/Lib9c/Lib9c.csproj
+++ b/Lib9c/Lib9c.csproj
@@ -23,6 +23,7 @@
     <PackageReference Include="DecimalMath.DecimalEx" Version="1.0.2" />
     <PackageReference Include="OptimizedPriorityQueue" Version="4.2.0" />
     <PackageReference Include="Serilog" Version="2.10.0" />
+    <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="8.0.0" />
     <PackageReference Include="SonarAnalyzer.CSharp" Version="8.38.0.46746">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>