diff --git a/EnvelopeGenerator.GeneratorAPI/Program.cs b/EnvelopeGenerator.GeneratorAPI/Program.cs
index fbc06fd9..02390820 100644
--- a/EnvelopeGenerator.GeneratorAPI/Program.cs
+++ b/EnvelopeGenerator.GeneratorAPI/Program.cs
@@ -129,7 +129,7 @@ try
                 {
                     var clientParams = deferredProvider.GetOptions<ClientParams>();
                     var publicKey = clientParams!.PublicKeys.Get(authTokenKeys.Issuer, authTokenKeys.Audience);
-                    return new List<SecurityKey>() { publicKey.SecurityKey };
+                    return [publicKey.SecurityKey];
                 },
                 ValidateIssuer = true,
                 ValidIssuer = authTokenKeys.Issuer,
@@ -205,10 +205,10 @@ try
     app.UseCors("AllowSpecificOriginsPolicy");
 
     // Localizer
-    string[] supportedCultureNames = { "de-DE", "en-US" };
-    IList<CultureInfo> list = supportedCultureNames.Select((string cn) => new CultureInfo(cn)).ToList();
-    CultureInfo cultureInfo = list.FirstOrDefault() ?? throw new ArgumentNullException("supportedCultureNames", "Supported cultures cannot be empty.");
-    RequestLocalizationOptions requestLocalizationOptions = new RequestLocalizationOptions
+    string[] supportedCultureNames = ["de-DE", "en-US"];
+    IList<CultureInfo> list = [.. supportedCultureNames.Select(cn => new CultureInfo(cn))];
+    var cultureInfo = list.FirstOrDefault() ?? throw new InvalidOperationException("There is no supported culture.");
+    var requestLocalizationOptions = new RequestLocalizationOptions
     {
         SupportedCultures = list,
         SupportedUICultures = list