diff --git a/ManagedCode.FeatureChecker/Feature.cs b/ManagedCode.FeatureChecker/Feature.cs
deleted file mode 100644
index bb59474..0000000
--- a/ManagedCode.FeatureChecker/Feature.cs
+++ /dev/null
@@ -1,6 +0,0 @@
-namespace ManagedCode.FeatureChecker;
-public class Feature
-{
-    public string Name { get; set; } = null!;
-    public FeatureStatus Status { get; set; }
-}
diff --git a/ManagedCode.FeatureChecker/FeatureChecker.cs b/ManagedCode.FeatureChecker/FeatureChecker.cs
index 40c5b95..79569d3 100644
--- a/ManagedCode.FeatureChecker/FeatureChecker.cs
+++ b/ManagedCode.FeatureChecker/FeatureChecker.cs
@@ -1,110 +1,46 @@
-namespace ManagedCode.FeatureChecker;
+using System.Collections.Immutable;
+
+namespace ManagedCode.FeatureChecker;
 
 public class FeatureChecker
 {
-    private readonly Dictionary<string, Feature> _features;
-
-    public FeatureChecker()
-    {
-        _features = new Dictionary<string, Feature>();
-    }
-
-    public event EventHandler FeatureAdded;
-    public event EventHandler FeatureRemoved;
-    public event EventHandler FeatureStatusChanged;
+    private readonly ImmutableDictionary<string, FeatureStatus> _features;
 
+    public int Count => _features.Count;
 
-    public bool TryAddFeature(string name, FeatureStatus status)
+    public FeatureChecker(FeatureHolder featureHolder)
     {
-        var feature = new Feature()
-        {
-            Name = name,
-            Status = status
-        };
-
-        return TryAddFeature(feature);
+        _features = featureHolder.Features;
     }
 
-    public bool TryAddFeature(Feature newFeature)
-    {
-        ThrowIfNull(newFeature, nameof(newFeature));
-        ValidateModel(newFeature);
-
-        return _features.TryAdd(newFeature.Name, newFeature);
-    }
-
-
-    public void RemoveFeature(string name)
-    {
-        ThrowIfNullOrEmpty(name, nameof(name));
-        _features.Remove(name);
-    }
-
-    public void RemoveAllFeatures() => _features.Clear();
-
-
     public bool IsFeatureExists(string name)
     {
-        ThrowIfNullOrEmpty(name, nameof(name));
-
-        return _features.ContainsKey(name);
+        return ValidateFeatureName(name)
+            ? _features.ContainsKey(name)
+            : false;
     }
 
     public bool TryGetFeatureStatus(string name, out FeatureStatus status)
     {
-        var result = TryGetFeatureByName(name, out Feature? feature);
-        status = feature?.Status ?? default;
+        status = default;
 
-        return result;
+        return ValidateFeatureName(name)
+            ? _features.TryGetValue(name, out status)
+            : false;
     }
 
-    public bool TryGetFeatureByName(string name, out Feature? feature)
+    public List<string> GetFeaturesByStatus(FeatureStatus status)
     {
-        ThrowIfNullOrEmpty(name, nameof(name));
-
-        return _features.TryGetValue(name, out feature);
+        return _features
+            .Where(x => x.Value == status)
+            .Select(x => x.Key)
+            .ToList();
     }
 
 
-    public Feature[] GetExistFeatures() => _features.Values.ToArray();
-
-    public IEnumerable<Feature> GetFeaturesByStatus(FeatureStatus status)
+    private bool ValidateFeatureName(string featureName)
     {
-        return _features.Values.Where(x => x.Status == status);
+        return !string.IsNullOrWhiteSpace(featureName);
     }
 
-
-    public bool TryUpdateFeatureStatus(string name, FeatureStatus status)
-    {
-        var result = TryGetFeatureByName(name, out Feature? feature);
-
-        if(result && feature != null)
-        {
-            feature.Status = FeatureStatus.Disabled;
-        }
-
-        return result;
-    }
-
-
-    private static void ThrowIfNull(object obj, string paramName)
-    {
-        if(obj == null)
-        {
-            throw new ArgumentNullException(paramName, $"Parameter is null.");
-        }
-    }
-
-    private static void ThrowIfNullOrEmpty(string arg, string argName)
-    {
-        if(string.IsNullOrWhiteSpace(arg))
-        {
-            throw new ArgumentException($"Invalid parameter '{argName}': {arg}.");
-        }
-    }
-
-    private static void ValidateModel(Feature feature)
-    {
-        //do some validation
-    }
 }
diff --git a/ManagedCode.FeatureChecker/FeatureHolder.cs b/ManagedCode.FeatureChecker/FeatureHolder.cs
new file mode 100644
index 0000000..a11ed60
--- /dev/null
+++ b/ManagedCode.FeatureChecker/FeatureHolder.cs
@@ -0,0 +1,61 @@
+using System.Collections.Immutable;
+using System.Text.Json.Serialization;
+
+namespace ManagedCode.FeatureChecker;
+public class FeatureHolder
+{
+    private Dictionary<string, FeatureStatus> _features;
+
+    [JsonInclude]
+    public ImmutableDictionary<string, FeatureStatus> Features
+    {
+        get => _features.ToImmutableDictionary();
+        private set => _features = new Dictionary<string, FeatureStatus>(value);
+    }
+
+
+    public FeatureHolder()
+    {
+        _features = new Dictionary<string, FeatureStatus>();
+    }
+
+    public bool TryAddFeature(string featureName, FeatureStatus status)
+    {
+        return ValidateFeatureName(featureName)
+            ? _features.TryAdd(featureName, status)
+            : false;
+    }
+
+    public bool TryGetFeatureStatus(string featureName, out FeatureStatus status)
+    {
+        status = default;
+
+        return ValidateFeatureName(featureName)
+            ? _features.TryGetValue(featureName, out status)
+            : false;
+    }
+
+    public void RemoveFeature(string featureName)
+    {
+        if(ValidateFeatureName(featureName))
+        {
+            _features.Remove(featureName);
+        }
+    }
+
+    public void UpdateFeatureStatus(string featureName, FeatureStatus status)
+    {
+        if(!ValidateFeatureName(featureName))
+        {
+            return;
+        }
+
+        _features[featureName] = status;
+    }
+
+
+    private bool ValidateFeatureName(string featureName)
+    {
+        return !string.IsNullOrWhiteSpace(featureName);
+    }
+}
diff --git a/ManagedCode.FeatureChecker/FeatureStatus.cs b/ManagedCode.FeatureChecker/FeatureStatus.cs
index 46edc00..00bfba5 100644
--- a/ManagedCode.FeatureChecker/FeatureStatus.cs
+++ b/ManagedCode.FeatureChecker/FeatureStatus.cs
@@ -3,6 +3,6 @@
 public enum FeatureStatus
 {
     Disabled,
-    Eanabled,
+    Enabled,
     Debug,
 }
diff --git a/ManagedCode.FeatureChecker/ManagedCode.FeatureChecker.csproj b/ManagedCode.FeatureChecker/ManagedCode.FeatureChecker.csproj
index 5f33f2c..f2075a7 100644
--- a/ManagedCode.FeatureChecker/ManagedCode.FeatureChecker.csproj
+++ b/ManagedCode.FeatureChecker/ManagedCode.FeatureChecker.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
         <ImplicitUsings>enable</ImplicitUsings>
@@ -15,7 +15,9 @@
         <PackageTags>managedcode, Tests, Detector, TestsDetector, unit tests</PackageTags>
     </PropertyGroup>
     <ItemGroup>
-      <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="7.0.0" />
+        <PackageReference Include="Microsoft.Extensions.Hosting.Abstractions" Version="7.0.0" />
+		<PackageReference Include="System.Collections.Immutable" Version="7.0.0" />
+		<PackageReference Include="System.Text.Json" Version="7.0.2" />
     </ItemGroup>
     
 </Project>
diff --git a/README.md b/README.md
index 52f0cc7..cc922d6 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,40 @@
 # FeatureChecker
+
+## Usage
+
+```js
+        var holder = new FeatureHolder();
+
+        holder.TryAddFeature("feature 1", default);
+        holder.TryAddFeature("feature 2", FeatureStatus.Enabled);
+        holder.TryAddFeature("feature 3", FeatureStatus.Debug);
+
+        holder.UpdateFeatureStatus("feature 3", FeatureStatus.Enabled);
+
+
+        var checker = new FeatureChecker(holder);
+
+        if(checker.IsFeatureExists("feature_name"))
+        {
+            //do some things...
+        }
+
+
+        var enabledFeatures = checker.GetFeaturesByStatus(FeatureStatus.Enabled);
+
+        foreach(var feat in enabledFeatures)
+        {
+            Console.WriteLine(feat);
+            //other code...
+        }
+
+
+        bool result = checker.TryGetFeatureStatus("myFeature", out FeatureStatus status);
+
+        if(result)
+        {
+            Console.WriteLine(status);
+            //other code...
+        }
+
+```
\ No newline at end of file