diff --git a/Runner/RegexDiffJob.cs b/Runner/RegexDiffJob.cs
index dcada4d..1a4ab4e 100644
--- a/Runner/RegexDiffJob.cs
+++ b/Runner/RegexDiffJob.cs
@@ -295,7 +295,7 @@ static string ParseCSharpLiteral(ReadOnlySpan<char> literal, out int indexOfEndi
                         'n' => '\n',
                         'f' => '\f',
                         'r' => '\r',
-                        'e' => '\e',
+                        'e' => (char)27,
                         '\\' => '\\',
                         '0' => '\0',
                         _ => throw new NotImplementedException(literal[i + 1].ToString())
diff --git a/Runner/Runner.csproj b/Runner/Runner.csproj
index 00a4fdc..a372f95 100644
--- a/Runner/Runner.csproj
+++ b/Runner/Runner.csproj
@@ -6,7 +6,6 @@
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <NoWarn>${NoWarn};IDE0305</NoWarn>
-    <LangVersion>preview</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>