diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..a63eb96
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use asdf
diff --git a/.tool-versions b/.tool-versions
new file mode 100644
index 0000000..95370d5
--- /dev/null
+++ b/.tool-versions
@@ -0,0 +1 @@
+dotnet-core 5.0.100
diff --git a/src/MfGames.Locking/MfGames.Locking.csproj b/src/MfGames.Locking/MfGames.Locking.csproj
index ba6bd73..a2d447d 100644
--- a/src/MfGames.Locking/MfGames.Locking.csproj
+++ b/src/MfGames.Locking/MfGames.Locking.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp2.1</TargetFramework>
+    <TargetFrameworks>netstandard2.0;net45;net5</TargetFrameworks>
     <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
     <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
     <AllowedOutputExtensionsInPackageBuildOutputFolder>$(AllowedOutputExtensionsInPackageBuildOutputFolder);.pdb</AllowedOutputExtensionsInPackageBuildOutputFolder>