diff --git a/src/AgileConfig.Server.Apisite/Controllers/api/ConfigController.cs b/src/AgileConfig.Server.Apisite/Controllers/api/ConfigController.cs
index f7042dd0..59c1f277 100644
--- a/src/AgileConfig.Server.Apisite/Controllers/api/ConfigController.cs
+++ b/src/AgileConfig.Server.Apisite/Controllers/api/ConfigController.cs
@@ -24,7 +24,7 @@ public class ConfigController : Controller
         private readonly IUserService _userService;
         private readonly IMemoryCache _cacheMemory;
         private readonly ITinyEventBus _tinyEventBus;
-        private readonly MeterService _meterService;
+        private readonly IMeterService _meterService;
 
         public ConfigController(
             IConfigService configService,
@@ -32,7 +32,7 @@ public ConfigController(
             IUserService userService,
             IMemoryCache cacheMemory,
             ITinyEventBus tinyEventBus,
-            MeterService meterService
+            IMeterService meterService
             )
         {
             _configService = configService;
@@ -95,7 +95,7 @@ public async Task<ActionResult<List<ApiConfigVM>>> GetAppConfig(string appId, [F
                 .SetAbsoluteExpiration(TimeSpan.FromSeconds(5));
             _cacheMemory?.Set(cacheKey, vms, cacheOp);
 
-            _meterService.PullAppConfigCounter.Add(1, new("appId", appId), new("env", env));
+            _meterService.PullAppConfigCounter?.Add(1, new("appId", appId), new("env", env));
 
             return vms;
         }
diff --git a/src/AgileConfig.Server.Apisite/InitService.cs b/src/AgileConfig.Server.Apisite/InitService.cs
index 5ffd055a..3fec6521 100644
--- a/src/AgileConfig.Server.Apisite/InitService.cs
+++ b/src/AgileConfig.Server.Apisite/InitService.cs
@@ -22,7 +22,7 @@ public class InitService : IHostedService
         private readonly IServiceScope _localServiceScope;
         public InitService(IServiceScopeFactory serviceScopeFactory,
             ISystemInitializationService systemInitializationService,
-            MeterService meterService,
+            IMeterService meterService,
             ILogger<InitService> logger)
         {
             _logger = logger;
diff --git a/src/AgileConfig.Server.Apisite/Metrics/IMeterService.cs b/src/AgileConfig.Server.Apisite/Metrics/IMeterService.cs
new file mode 100644
index 00000000..120456fd
--- /dev/null
+++ b/src/AgileConfig.Server.Apisite/Metrics/IMeterService.cs
@@ -0,0 +1,16 @@
+using System.Diagnostics.Metrics;
+
+namespace AgileConfig.Server.Apisite.Metrics
+{
+    public interface IMeterService
+    {
+        ObservableGauge<int> AppGauge { get; }
+        ObservableGauge<int> ClientGauge { get; }
+        ObservableGauge<int> ConfigGauge { get; }
+        ObservableGauge<int> NodeGauge { get; }
+        Counter<long> PullAppConfigCounter { get; }
+        ObservableGauge<int> ServiceGauge { get; }
+
+        void Start();
+    }
+}
\ No newline at end of file
diff --git a/src/AgileConfig.Server.Apisite/Metrics/MeterService.cs b/src/AgileConfig.Server.Apisite/Metrics/MeterService.cs
index 943c3941..d734660d 100644
--- a/src/AgileConfig.Server.Apisite/Metrics/MeterService.cs
+++ b/src/AgileConfig.Server.Apisite/Metrics/MeterService.cs
@@ -6,7 +6,7 @@
 
 namespace AgileConfig.Server.Apisite.Metrics
 {
-    public class MeterService
+    public class MeterService : IMeterService
     {
         public const string MeterName = "AgileConfigMeter";
 
diff --git a/src/AgileConfig.Server.Apisite/Startup.cs b/src/AgileConfig.Server.Apisite/Startup.cs
index 238aa422..151b058a 100644
--- a/src/AgileConfig.Server.Apisite/Startup.cs
+++ b/src/AgileConfig.Server.Apisite/Startup.cs
@@ -92,7 +92,7 @@ public void ConfigureServices(IServiceCollection services)
 
             services.AddOIDC();
 
-            services.AddSingleton<MeterService>();
+            services.AddSingleton<IMeterService, MeterService>();
 
             services.AddOpenTelemetry()
                     .ConfigureResource(resource => resource.AddService(Program.AppName))
diff --git a/test/ApiSiteTests/TestApiConfigController.cs b/test/ApiSiteTests/TestApiConfigController.cs
index 4624cf29..22593b05 100644
--- a/test/ApiSiteTests/TestApiConfigController.cs
+++ b/test/ApiSiteTests/TestApiConfigController.cs
@@ -9,6 +9,7 @@
 using Microsoft.Extensions.Caching.Memory;
 using AgileConfig.Server.Apisite.Controllers.api.Models;
 using AgileConfig.Server.Common.EventBus;
+using AgileConfig.Server.Apisite.Metrics;
 
 namespace ApiSiteTests;
 
@@ -64,12 +65,15 @@ List<Config> newConfigs()
         var appBasicAuthService = new Mock<IAppBasicAuthService>();
         var userSErvice = new Mock<IUserService>();
         var eventBus = new Mock<ITinyEventBus>();
+        var meterService = new Mock<IMeterService>();
 
         var ctrl = new ConfigController(
             configService.Object,
             appService.Object,
             userSErvice.Object,
-            memoryCache, eventBus.Object);
+            memoryCache, eventBus.Object,
+            meterService.Object
+            );
         var act = await ctrl.GetAppConfig("001", "DEV");
 
         Assert.IsNotNull(act);
@@ -91,7 +95,9 @@ App newApp1()
             configService.Object,
             appService.Object,
             userSErvice.Object,
-            memoryCache, eventBus.Object);
+            memoryCache, eventBus.Object,
+            meterService.Object
+            );
         act = await ctrl.GetAppConfig("001", "DEV");
 
         Assert.IsNotNull(act);