diff --git a/src/Orleans.Multitenant/Extensions.cs b/src/Orleans.Multitenant/Extensions.cs
index 3674740..85db65f 100644
--- a/src/Orleans.Multitenant/Extensions.cs
+++ b/src/Orleans.Multitenant/Extensions.cs
@@ -192,7 +192,12 @@ public static IServiceCollection AddMultitenantGrainStorage<TGrainStorage, TGrai
 /// <param name="providerName">The name - without the tenant id - of the provider; can be used to access named provider services that are not tenant specific</param>
 /// <param name="tenantProviderName">The name - including the tenant id - of the tenant provider; can be used to access named provider services that are tenant specific</param>
 /// <param name="options">The options to pass to the provider. Note that configureTenantOptions and options validation have already been executed on this</param>
-/// <returns>The tenant storage provider construction parameters to pass to DI. Don't include <paramref name="tenantProviderName"/> in these; it is added automatically</returns>
+/// <returns>
+/// The complete set of tenant storage provider construction parameters to pass to DI.<br />
+/// When this factory is provided, it has full ownership of the parameter list — <paramref name="tenantProviderName"/> is NOT prepended automatically.<br />
+/// This allows providers with non-standard constructor signatures (e.g. RavenDbGrainStorage, which does not accept a string name as its first parameter) to work correctly.<br />
+/// For standard providers that DO follow the <c>(string name, TOptions options)</c> convention, omit this factory and rely on the default behavior.
+/// </returns>
 public delegate object[] GrainStorageProviderParametersFactory<in TGrainStorageOptions>(
     IServiceProvider services,
     string providerName,
diff --git a/src/Orleans.Multitenant/Internal/SiloLifecycle.cs b/src/Orleans.Multitenant/Internal/SiloLifecycle.cs
index a8ee23c..ca20492 100644
--- a/src/Orleans.Multitenant/Internal/SiloLifecycle.cs
+++ b/src/Orleans.Multitenant/Internal/SiloLifecycle.cs
@@ -26,7 +26,7 @@ sealed record LifecycleStartupRecording(int HighestCompletedStageOnParticipate,
 
 sealed class SiloLifecycleRepeater : IRepeatedSiloLifecycleObservable
 {
-    internal static int[] AllServiceLifecycleStages { get; } =
+    internal static int[] AllServiceLifecycleStages => field ??=
         [.. typeof(ServiceLifecycleStage).GetFields(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Static).Where(fi => fi.FieldType == typeof(int))
         .Select(fi => (int)(fi.GetValue(null) ?? throw new InvalidCastException("static int field cannot have value null"))).OrderBy(value => value)];
 
diff --git a/src/Orleans.Multitenant/Internal/TenantGrainStorageFactory.cs b/src/Orleans.Multitenant/Internal/TenantGrainStorageFactory.cs
index 87c3ed7..dd621a5 100644
--- a/src/Orleans.Multitenant/Internal/TenantGrainStorageFactory.cs
+++ b/src/Orleans.Multitenant/Internal/TenantGrainStorageFactory.cs
@@ -86,8 +86,15 @@ public IGrainStorage Create(string tenantId)
         if (options is IStorageProviderSerializerOptions serializerOptions && serializerOptions.GrainStorageSerializer == default)
             serializerOptions.GrainStorageSerializer = services.GetKeyedService<IGrainStorageSerializer>(name) ?? services.GetRequiredService<IGrainStorageSerializer>();
 
-        List<object> providerParameters = [tenantProviderName];
-        providerParameters.AddRange(getProviderParameters?.Invoke(services, name, tenantProviderName, options) ?? [options]);
+        // If getProviderParameters is supplied, the caller takes full ownership of the constructor
+        // parameter list (needed for providers like RavenDbGrainStorage whose constructors do not
+        // follow the conventional (string name, TOptions options) signature).
+        // Otherwise, fall back to the original convention: [tenantProviderName, options].
+        // This keeps backward compatibility for standard providers (Azure, AdoNet, etc.) and is
+        // suitable to PR upstream to VincentH-Net/Orleans.Multitenant.
+        List<object> providerParameters = getProviderParameters is not null
+            ? [.. getProviderParameters.Invoke(services, name, tenantProviderName, options)]
+            : [tenantProviderName, options];
 
         var configuredOptions = providerParameters.OfType<TGrainStorageOptions>().SingleOrDefault();
         if (configuredOptions is not null)
diff --git a/src/Tests/UnitTests/GrainStorageProviderParametersTests.cs b/src/Tests/UnitTests/GrainStorageProviderParametersTests.cs
new file mode 100644
index 0000000..f5b77ce
--- /dev/null
+++ b/src/Tests/UnitTests/GrainStorageProviderParametersTests.cs
@@ -0,0 +1,93 @@
+using Microsoft.Extensions.DependencyInjection;
+using Orleans.Configuration;
+using Orleans.Storage;
+using Orleans.TestingHost;
+
+namespace OrleansMultitenant.Tests.UnitTests;
+
+public interface ITestGrain : IGrainWithStringKey
+{
+    Task UseStorage();
+}
+
+public class TestGrain([PersistentState("state")] IPersistentState<TestState> state) : Grain, ITestGrain
+{
+    public Task UseStorage() => state.ReadStateAsync();
+}
+
+[GenerateSerializer]
+public class TestState { }
+
+public sealed class GrainStorageProviderParametersTests(GrainStorageProviderParametersTests.ClusterFixture fixture) : IClassFixture<GrainStorageProviderParametersTests.ClusterFixture>
+{
+    readonly TestCluster cluster = fixture.Cluster;
+
+    [Fact]
+    public async Task CustomStorageProvider_IsInstantiatedWithCorrectParameters()
+    {
+        string tenantId = "TenantA";
+        var grain = cluster.Client.ForTenant(tenantId).GetGrain<ITestGrain>(Guid.NewGuid().ToString());
+
+        await grain.UseStorage();
+
+        object[]? parameters = CustomGrainStorage.GetLastParameters();
+        Assert.NotNull(parameters);
+        Assert.Equal(3, parameters.Length);
+        Assert.StartsWith("TenantA_", (string)parameters[0], StringComparison.Ordinal);
+        _ = Assert.IsType<CustomOptions>(parameters[1]);
+        Assert.Equal("ExtraValue", (string)parameters[2]);
+    }
+
+    public class CustomGrainStorage : IGrainStorage
+    {
+        static object[]? lastParameters;
+        public static object[]? GetLastParameters() => lastParameters;
+
+        public CustomGrainStorage(string name, CustomOptions options, string extraParameter)
+            => lastParameters = [name, options, extraParameter];
+
+        public Task ClearStateAsync<T>(string stateName, GrainId grainId, IGrainState<T> grainState) => Task.CompletedTask;
+        public Task ReadStateAsync<T>(string stateName, GrainId grainId, IGrainState<T> grainState) => Task.CompletedTask;
+        public Task WriteStateAsync<T>(string stateName, GrainId grainId, IGrainState<T> grainState) => Task.CompletedTask;
+    }
+
+    public class CustomOptions
+    {
+        public string SomeValue { get; set; } = string.Empty;
+    }
+
+    public class CustomOptionsValidator(CustomOptions options, string name) : IConfigurationValidator
+    {
+        public void ValidateConfiguration()
+        {
+            _ = options;
+            _ = name;
+        }
+    }
+
+    public sealed class ClusterFixture : IDisposable
+    {
+        public ClusterFixture()
+        {
+            var builder = new TestClusterBuilder()
+                .AddSiloBuilderConfigurator<SiloConfigurator>();
+
+            Cluster = builder.Build();
+            Cluster.Deploy();
+        }
+
+        public void Dispose() => Cluster.StopAllSilos();
+
+        public TestCluster Cluster { get; }
+
+        sealed class SiloConfigurator : ISiloConfigurator
+        {
+            public void Configure(ISiloBuilder siloBuilder) => siloBuilder
+                .AddMultitenantGrainStorageAsDefault<CustomGrainStorage, CustomOptions, CustomOptionsValidator>(
+                    (siloBuilder, name) => siloBuilder.ConfigureServices(services =>
+                        services.AddKeyedSingleton<IGrainStorage>(name, (sp, key) => new CustomGrainStorage((string)key!, new CustomOptions(), "default"))),
+                    getProviderParameters: (services, name, tenantProviderName, options) => [tenantProviderName, options, "ExtraValue"]
+                );
+        }
+    }
+}