diff --git a/Requests/CreateTTSVoice.cs b/Requests/CreateTTSVoice.cs
index 4b49813..b5da7e5 100644
--- a/Requests/CreateTTSVoice.cs
+++ b/Requests/CreateTTSVoice.cs
@@ -13,7 +13,7 @@ namespace HermesSocketServer.Requests
         private ILogger _logger;
         private Random _random;
 
-        public CreateTTSVoice(VoiceStore voices, ILogger logger)
+        public CreateTTSVoice(IStore<string, TTSVoice> voices, ILogger logger)
         {
             _voices = voices;
             _logger = logger;
diff --git a/Requests/DeleteTTSVoice.cs b/Requests/DeleteTTSVoice.cs
index 0142097..c18b4a5 100644
--- a/Requests/DeleteTTSVoice.cs
+++ b/Requests/DeleteTTSVoice.cs
@@ -12,7 +12,7 @@ namespace HermesSocketServer.Requests
         private IStore<string, TTSVoice> _voices;
         private ILogger _logger;
 
-        public DeleteTTSVoice(VoiceStore voices, ILogger logger)
+        public DeleteTTSVoice(IStore<string, TTSVoice> voices, ILogger logger)
         {
             _voices = voices;
             _logger = logger;
diff --git a/Requests/GetDefaultTTSVoice.cs b/Requests/GetDefaultTTSVoice.cs
index b85de29..3d61a98 100644
--- a/Requests/GetDefaultTTSVoice.cs
+++ b/Requests/GetDefaultTTSVoice.cs
@@ -8,11 +8,11 @@ namespace HermesSocketServer.Requests
     {
         public string Name => "get_default_tts_voice";
         public string[] RequiredKeys => [];
-        private readonly UserStore _users;
+        private readonly IStore<string, User> _users;
         private readonly ServerConfiguration _configuration;
         private readonly ILogger _logger;
 
-        public GetDefaultTTSVoice(UserStore users, ServerConfiguration configuration, ILogger logger)
+        public GetDefaultTTSVoice(IStore<string, User> users, ServerConfiguration configuration, ILogger logger)
         {
             _users = users;
             _configuration = configuration;
diff --git a/Requests/GetTTSVoices.cs b/Requests/GetTTSVoices.cs
index 9763438..c6bcd83 100644
--- a/Requests/GetTTSVoices.cs
+++ b/Requests/GetTTSVoices.cs
@@ -9,10 +9,10 @@ namespace HermesSocketServer.Requests
     {
         public string Name => "get_tts_voices";
         public string[] RequiredKeys => [];
-        private VoiceStore _voices;
+        private IStore<string, TTSVoice> _voices;
         private ILogger _logger;
 
-        public GetTTSVoices(VoiceStore voices, ILogger logger)
+        public GetTTSVoices(IStore<string, TTSVoice> voices, ILogger logger)
         {
             _voices = voices;
             _logger = logger;
diff --git a/Requests/UpdateDefaultTTSVoice.cs b/Requests/UpdateDefaultTTSVoice.cs
index 6dfc2f3..e4d58aa 100644
--- a/Requests/UpdateDefaultTTSVoice.cs
+++ b/Requests/UpdateDefaultTTSVoice.cs
@@ -8,10 +8,10 @@ namespace HermesSocketServer.Requests
     {
         public string Name => "update_default_tts_voice";
         public string[] RequiredKeys => ["user", "voice"];
-        private UserStore _users;
+        private IStore<string, User> _users;
         private ILogger _logger;
 
-        public UpdateDefaultTTSVoice(UserStore users, ILogger logger)
+        public UpdateDefaultTTSVoice(IStore<string, User> users, ILogger logger)
         {
             _users = users;
             _logger = logger;
diff --git a/Requests/UpdateRedeemableAction.cs b/Requests/UpdateRedeemableAction.cs
index 820db3a..70b560b 100644
--- a/Requests/UpdateRedeemableAction.cs
+++ b/Requests/UpdateRedeemableAction.cs
@@ -41,11 +41,7 @@ namespace HermesSocketServer.Requests
                 Type = type,
             };
 
-            bool result = channel.Actions.Modify(name, action =>
-            {
-                action.Type = type;
-                action.Data = dict;
-            });
+            bool result = channel.Actions.Modify(name, action);
             if (result)
             {
                 _logger.Information($"Added redeemable action to channel [name: {name}][type: {type}][channel: {channel.Id}]");
diff --git a/Requests/UpdateRedemption.cs b/Requests/UpdateRedemption.cs
index 77205b1..f623dff 100644
--- a/Requests/UpdateRedemption.cs
+++ b/Requests/UpdateRedemption.cs
@@ -1,3 +1,4 @@
+using HermesSocketLibrary.Requests.Messages;
 using HermesSocketServer.Models;
 using ILogger = Serilog.ILogger;
 
@@ -25,16 +26,16 @@ namespace HermesSocketServer.Requests
                 return Task.FromResult(RequestResult.Failed("Order must be an integer."));
             bool state = data["state"].ToString()?.ToLower() == "true";
 
-            bool result = channel.Redemptions.Modify(id, r =>
-            {
-                if (r.UserId != channel.Id)
-                    return;
+            Redemption redemption = new Redemption() {
+                Id = id,
+                UserId = channel.Id,
+                RedemptionId = redemptionId,
+                ActionName = actionName,
+                Order = order,
+                State = state,
+            };
 
-                r.RedemptionId = redemptionId;
-                r.ActionName = actionName;
-                r.Order = order;
-                r.State = state;
-            });
+            bool result = channel.Redemptions.Modify(id, redemption);
 
             var r = channel.Redemptions.Get(id);
             if (result)
diff --git a/Requests/UpdateTTSFilter.cs b/Requests/UpdateTTSFilter.cs
index 93af209..d1df472 100644
--- a/Requests/UpdateTTSFilter.cs
+++ b/Requests/UpdateTTSFilter.cs
@@ -35,12 +35,7 @@ namespace HermesSocketServer.Requests
                 Flag = flag,
             };
 
-            bool result = channel.Filters.Modify(id, f => {
-                f.Search = search;
-                f.Replace = replace;
-                if (flag >= 0)
-                    f.Flag = flag;
-            });
+            bool result = channel.Filters.Modify(id, filter);
 
             if (result)
             {
diff --git a/Requests/UpdateTTSVoice.cs b/Requests/UpdateTTSVoice.cs
index f9bce32..ed8b13b 100644
--- a/Requests/UpdateTTSVoice.cs
+++ b/Requests/UpdateTTSVoice.cs
@@ -12,7 +12,7 @@ namespace HermesSocketServer.Requests
         private IStore<string, TTSVoice> _voices;
         private ILogger _logger;
 
-        public UpdateTTSVoice(VoiceStore voices, ILogger logger)
+        public UpdateTTSVoice(IStore<string, TTSVoice> voices, ILogger logger)
         {
             _voices = voices;
             _logger = logger;
diff --git a/Services/ChannelManager.cs b/Services/ChannelManager.cs
index df71f14..1f7f676 100644
--- a/Services/ChannelManager.cs
+++ b/Services/ChannelManager.cs
@@ -7,14 +7,14 @@ namespace HermesSocketServer.Services
 {
     public class ChannelManager
     {
-        private readonly UserStore _users;
+        private readonly IStore<string, User> _users;
         private readonly Database _database;
         private readonly ServerConfiguration _configuration;
         private readonly Serilog.ILogger _logger;
         private readonly IDictionary<string, Channel> _channels;
         private readonly object _lock;
 
-        public ChannelManager(UserStore users, Database database, ServerConfiguration configuration, Serilog.ILogger logger)
+        public ChannelManager(IStore<string, User> users, Database database, ServerConfiguration configuration, Serilog.ILogger logger)
         {
             _users = users;
             _database = database;
diff --git a/Services/DatabaseService.cs b/Services/DatabaseService.cs
index 39f12ee..1b6463d 100644
--- a/Services/DatabaseService.cs
+++ b/Services/DatabaseService.cs
@@ -1,4 +1,6 @@
 using HermesSocketLibrary.db;
+using HermesSocketLibrary.Requests.Messages;
+using HermesSocketServer.Models;
 using HermesSocketServer.Store;
 
 namespace HermesSocketServer.Services
@@ -6,12 +8,12 @@ namespace HermesSocketServer.Services
     public class DatabaseService : BackgroundService
     {
         private readonly ChannelManager _channels;
-        private readonly VoiceStore _voices;
-        private readonly UserStore _users;
+        private readonly IStore<string, TTSVoice> _voices;
+        private readonly IStore<string, User> _users;
         private readonly ServerConfiguration _configuration;
         private readonly Serilog.ILogger _logger;
 
-        public DatabaseService(ChannelManager channels, VoiceStore voices, UserStore users, ServerConfiguration configuration, Serilog.ILogger logger)
+        public DatabaseService(ChannelManager channels, IStore<string, TTSVoice> voices, IStore<string, User> users, ServerConfiguration configuration, Serilog.ILogger logger)
         {
             _channels = channels;
             _voices = voices;
diff --git a/Socket/Handlers/HermesLoginHandler.cs b/Socket/Handlers/HermesLoginHandler.cs
index 730edef..78f05c4 100644
--- a/Socket/Handlers/HermesLoginHandler.cs
+++ b/Socket/Handlers/HermesLoginHandler.cs
@@ -12,14 +12,14 @@ namespace HermesSocketServer.Socket.Handlers
         public int OperationCode { get; } = 1;
 
         private readonly ChannelManager _manager;
-        private readonly VoiceStore _voices;
+        private readonly IStore<string, TTSVoice> _voices;
         private readonly ServerConfiguration _configuration;
         private readonly Database _database;
         private readonly HermesSocketManager _sockets;
         private readonly ILogger _logger;
         private readonly object _lock;
 
-        public HermesLoginHandler(ChannelManager manager, VoiceStore voices, ServerConfiguration configuration, Database database, HermesSocketManager sockets, ILogger logger)
+        public HermesLoginHandler(ChannelManager manager, IStore<string, TTSVoice> voices, ServerConfiguration configuration, Database database, HermesSocketManager sockets, ILogger logger)
         {
             _manager = manager;
             _voices = voices;
diff --git a/Startup.cs b/Startup.cs
index 907449a..0eb66bf 100644
--- a/Startup.cs
+++ b/Startup.cs
@@ -17,6 +17,8 @@ using HermesSocketServer.Store;
 using HermesSocketServer.Services;
 using HermesSocketServer.Store.Internal;
 using Microsoft.Extensions.DependencyInjection;
+using HermesSocketLibrary.Requests.Messages;
+using HermesSocketServer.Models;
 
 
 var yamlDeserializer = new DeserializerBuilder()
@@ -88,8 +90,8 @@ if (configuration.Database.Tables != null)
 }
 
 // Stores
-s.AddSingleton<VoiceStore>();
-s.AddSingleton<UserStore>();
+s.AddSingleton<IStore<string, TTSVoice>, VoiceStore>();
+s.AddSingleton<IStore<string, User>, UserStore>();
 
 // Request handlers
 s.AddSingleton<IRequest, CreatePolicy>();
diff --git a/Store/ActionStore.cs b/Store/ActionStore.cs
index 2b12b00..27352fe 100644
--- a/Store/ActionStore.cs
+++ b/Store/ActionStore.cs
@@ -40,10 +40,23 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, RedeemableAction value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.UserId, nameof(value.UserId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.Name, nameof(value.Name));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.Type, nameof(value.Type));
+            ArgumentNullException.ThrowIfNull(value.Data, nameof(value.Data));
         }
 
-        protected override void OnInitialModify(string key, RedeemableAction value)
+        protected override void OnInitialModify(string key, RedeemableAction oldValue, RedeemableAction newValue)
         {
+            ArgumentNullException.ThrowIfNull(newValue, nameof(newValue));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.UserId, nameof(newValue.UserId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.Name, nameof(newValue.Name));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.Type, nameof(newValue.Type));
+            ArgumentNullException.ThrowIfNull(newValue.Data, nameof(newValue.Data));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.UserId, newValue.UserId, nameof(oldValue.UserId));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.Name, newValue.Name, nameof(oldValue.Name));
         }
     }
 }
\ No newline at end of file
diff --git a/Store/ChatterStore.cs b/Store/ChatterStore.cs
index 8a8091b..5f62150 100644
--- a/Store/ChatterStore.cs
+++ b/Store/ChatterStore.cs
@@ -38,10 +38,21 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, ChatterVoice value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.UserId, nameof(value.UserId));
+            ArgumentOutOfRangeException.ThrowIfNegativeOrZero(value.ChatterId, nameof(value.ChatterId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.VoiceId, nameof(value.VoiceId));
         }
 
-        protected override void OnInitialModify(string key, ChatterVoice value)
+        protected override void OnInitialModify(string key, ChatterVoice oldValue, ChatterVoice newValue)
         {
+            ArgumentNullException.ThrowIfNull(newValue, nameof(newValue));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.UserId, nameof(newValue.UserId));
+            ArgumentOutOfRangeException.ThrowIfNegativeOrZero(newValue.ChatterId, nameof(newValue.ChatterId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.VoiceId, nameof(newValue.VoiceId));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.UserId, newValue.UserId, nameof(oldValue.UserId));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.ChatterId, newValue.ChatterId, nameof(oldValue.ChatterId));
         }
     }
 }
\ No newline at end of file
diff --git a/Store/IStore.cs b/Store/IStore.cs
index 09814c0..ac75903 100644
--- a/Store/IStore.cs
+++ b/Store/IStore.cs
@@ -5,9 +5,10 @@ namespace HermesSocketServer.Store
         V? Get(K key);
         IDictionary<K, V> Get();
         Task Load();
-        bool Modify(K? key, Action<V> action);
+        bool Modify(K? key, Action<V> modify);
+        bool Modify(K? key, V value);
         bool Remove(K? key);
         Task Save();
-        bool Set(K? key, V? value);
+        bool Set(K? key, V value);
     }
 }
\ No newline at end of file
diff --git a/Store/Internal/ComplexAutoSavedStore.cs b/Store/Internal/ComplexAutoSavedStore.cs
index d648fb2..03bdfd1 100644
--- a/Store/Internal/ComplexAutoSavedStore.cs
+++ b/Store/Internal/ComplexAutoSavedStore.cs
@@ -48,7 +48,7 @@ namespace HermesSocketServer.Store.Internal
                 async (query, list) => await _generator.DoPreparedStatement(_database, query, list, _table.KeyColumns));
         }
 
-        private async Task GenerateQuery(IList<K> keys, Func<int, string> generate, Func<string, IEnumerable<K>, IEnumerable<V>, Task<int>> execute)
+        private async Task GenerateQuery(IList<K> keys, Func<int, string> generate, Func<string, IEnumerable<K>, IEnumerable<V?>, Task<int>> execute)
         {
             ImmutableList<K>? list = null;
             lock (_lock)
diff --git a/Store/Internal/GroupedSaveStore.cs b/Store/Internal/GroupedSaveStore.cs
index a891b2d..50585b7 100644
--- a/Store/Internal/GroupedSaveStore.cs
+++ b/Store/Internal/GroupedSaveStore.cs
@@ -24,7 +24,7 @@ namespace HermesSocketServer.Store.Internal
 
         public abstract Task Load();
         protected abstract void OnInitialAdd(K key, V value);
-        protected abstract void OnInitialModify(K key, V value);
+        protected abstract void OnInitialModify(K key, V value, V newValue);
         protected abstract void OnPostRemove(K key, V value);
         public abstract Task Save();
 
@@ -46,7 +46,28 @@ namespace HermesSocketServer.Store.Internal
             }
         }
 
-        public bool Modify(K? key, Action<V> action)
+        public bool Modify(K? key, V value)
+        {
+            if (key == null)
+                return false;
+
+            lock (_lock)
+            {
+                if (_store.TryGetValue(key, out V? oldValue))
+                {
+                    OnInitialModify(key, oldValue, value);
+                    _store[key] = value;
+                    if (!_added.Contains(key) && !_modified.Contains(key))
+                    {
+                        _modified.Add(key);
+                    }
+                    return true;
+                }
+            }
+            return false;
+        }
+
+        public bool Modify(K? key, Action<V> modify)
         {
             if (key == null)
                 return false;
@@ -55,11 +76,7 @@ namespace HermesSocketServer.Store.Internal
             {
                 if (_store.TryGetValue(key, out V? value))
                 {
-                    if (value == null)
-                        return false;
-
-                    OnInitialModify(key, value);
-                    action(value);
+                    modify(value);
                     if (!_added.Contains(key) && !_modified.Contains(key))
                     {
                         _modified.Add(key);
@@ -97,9 +114,9 @@ namespace HermesSocketServer.Store.Internal
             return false;
         }
 
-        public bool Set(K? key, V? value)
+        public bool Set(K? key, V value)
         {
-            if (key == null || value == null)
+            if (key == null)
                 return false;
 
             lock (_lock)
@@ -108,7 +125,7 @@ namespace HermesSocketServer.Store.Internal
                 {
                     if (fetched != value)
                     {
-                        OnInitialModify(key, value);
+                        OnInitialModify(key, fetched, value);
                         _store[key] = value;
                         if (!_added.Contains(key) && !_modified.Contains(key))
                         {
diff --git a/Store/PolicyStore.cs b/Store/PolicyStore.cs
index 28868e7..7924e34 100644
--- a/Store/PolicyStore.cs
+++ b/Store/PolicyStore.cs
@@ -41,10 +41,29 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, Policy value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.UserId, nameof(value.UserId));
+            ArgumentOutOfRangeException.ThrowIfEqual(value.GroupId, default, nameof(value.GroupId));
+            ArgumentOutOfRangeException.ThrowIfNegativeOrZero(value.Usage, nameof(value.Usage));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Usage, 99, nameof(value.Usage));
+            ArgumentOutOfRangeException.ThrowIfNegativeOrZero(value.Span, nameof(value.Span));
+            ArgumentOutOfRangeException.ThrowIfLessThan(value.Span, 1000, nameof(value.Span));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Span, 86400, nameof(value.Span));
         }
 
-        protected override void OnInitialModify(string key, Policy value)
+        protected override void OnInitialModify(string key, Policy oldValue, Policy newValue)
         {
+            ArgumentNullException.ThrowIfNull(newValue, nameof(newValue));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.UserId, nameof(newValue.UserId));
+            ArgumentOutOfRangeException.ThrowIfEqual(newValue.GroupId, default, nameof(newValue.GroupId));
+            ArgumentOutOfRangeException.ThrowIfNegativeOrZero(newValue.Usage, nameof(newValue.Usage));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(newValue.Usage, 99, nameof(newValue.Usage));
+            ArgumentOutOfRangeException.ThrowIfNegativeOrZero(newValue.Span, nameof(newValue.Span));
+            ArgumentOutOfRangeException.ThrowIfLessThan(newValue.Span, 1000, nameof(newValue.Span));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(newValue.Span, 86400, nameof(newValue.Span));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.Id, newValue.Id, nameof(oldValue.Id));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.UserId, newValue.UserId, nameof(oldValue.UserId));
         }
 
         protected override void OnPostRemove(string key, Policy value)
diff --git a/Store/RedemptionStore.cs b/Store/RedemptionStore.cs
index 6bb1bf7..515e7d6 100644
--- a/Store/RedemptionStore.cs
+++ b/Store/RedemptionStore.cs
@@ -41,13 +41,32 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, Redemption value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.UserId, nameof(value.UserId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.RedemptionId, nameof(value.RedemptionId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.ActionName, nameof(value.ActionName));
+            ArgumentNullException.ThrowIfNull(value.State, nameof(value.State));
+            ArgumentNullException.ThrowIfNull(value.Order, nameof(value.Order));
+            ArgumentOutOfRangeException.ThrowIfNegative(value.Order, nameof(value.Order));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Order, 99, nameof(value.Order));
         }
 
-        protected override void OnInitialModify(string key, Redemption value)
+        protected override void OnInitialModify(string key, Redemption oldValue, Redemption newValue)
         {
+            ArgumentNullException.ThrowIfNull(newValue);
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.UserId, nameof(newValue.UserId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.RedemptionId, nameof(newValue.RedemptionId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.ActionName, nameof(newValue.ActionName));
+            ArgumentNullException.ThrowIfNull(newValue.State, nameof(newValue.State));
+            ArgumentNullException.ThrowIfNull(newValue.Order, nameof(newValue.Order));
+            ArgumentOutOfRangeException.ThrowIfNegative(newValue.Order, nameof(newValue.Order));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(newValue.Order, 99, nameof(newValue.Order));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.Id, newValue.Id, nameof(newValue.Id));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.UserId, newValue.UserId, nameof(newValue.UserId));
         }
 
-        protected override void OnPostRemove(string key, Redemption value)
+        protected override void OnPostRemove(string key, Redemption? value)
         {
         }
     }
diff --git a/Store/TTSFilterStore.cs b/Store/TTSFilterStore.cs
index 34b1b41..8295563 100644
--- a/Store/TTSFilterStore.cs
+++ b/Store/TTSFilterStore.cs
@@ -1,3 +1,4 @@
+using System.Text.RegularExpressions;
 using HermesSocketLibrary.db;
 using HermesSocketLibrary.Requests.Messages;
 using HermesSocketServer.Store.Internal;
@@ -40,10 +41,27 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, TTSWordFilter value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.Id, nameof(value.Id));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.UserId, nameof(value.UserId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.Search, nameof(value.Search));
+            ArgumentNullException.ThrowIfNull(value.Replace, nameof(value.Replace));
+            ArgumentOutOfRangeException.ThrowIfNegative(value.Flag, nameof(value.Flag));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Flag, 2047, nameof(value.Flag));
         }
 
-        protected override void OnInitialModify(string key, TTSWordFilter value)
+        protected override void OnInitialModify(string key, TTSWordFilter oldValue, TTSWordFilter newValue)
         {
+            ArgumentNullException.ThrowIfNull(newValue, nameof(newValue));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.Id, nameof(newValue.Id));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.UserId, nameof(newValue.UserId));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.Search, nameof(newValue.Search));
+            ArgumentNullException.ThrowIfNull(newValue.Replace, nameof(newValue.Replace));
+            ArgumentOutOfRangeException.ThrowIfNegative(newValue.Flag, nameof(newValue.Flag));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(newValue.Flag, 2047, nameof(newValue.Flag));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.Id, newValue.Id, nameof(oldValue.Id));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.UserId, newValue.UserId, nameof(oldValue.UserId));
         }
 
         protected override void OnPostRemove(string key, TTSWordFilter value)
diff --git a/Store/UserStore.cs b/Store/UserStore.cs
index 787e643..fff9284 100644
--- a/Store/UserStore.cs
+++ b/Store/UserStore.cs
@@ -39,7 +39,7 @@ namespace HermesSocketServer.Store
         {
         }
 
-        protected override void OnInitialModify(string key, User value)
+        protected override void OnInitialModify(string key, User oldValue, User newValue)
         {
         }
 
diff --git a/Store/VoiceStateStore.cs b/Store/VoiceStateStore.cs
index 60855b8..394b974 100644
--- a/Store/VoiceStateStore.cs
+++ b/Store/VoiceStateStore.cs
@@ -41,11 +41,23 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, TTSVoiceState value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
             _idValidator.Check(value.Id);
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.Id, nameof(value.Id));
+            ArgumentException.ThrowIfNullOrWhiteSpace(value.UserId, nameof(value.UserId));
+            ArgumentNullException.ThrowIfNull(value.Enabled, nameof(value.Enabled));
         }
 
-        protected override void OnInitialModify(string key, TTSVoiceState value)
+        protected override void OnInitialModify(string key, TTSVoiceState oldValue, TTSVoiceState newValue)
         {
+            ArgumentNullException.ThrowIfNull(newValue, nameof(newValue));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.Id, nameof(newValue.Id));
+            ArgumentException.ThrowIfNullOrWhiteSpace(newValue.UserId, nameof(newValue.UserId));
+            ArgumentNullException.ThrowIfNull(newValue.Enabled, nameof(newValue.Enabled));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.Id, newValue.Id, nameof(oldValue.Id));
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.UserId, newValue.UserId, nameof(oldValue.UserId));
+            ArgumentOutOfRangeException.ThrowIfEqual(oldValue.Enabled, newValue.Enabled, nameof(oldValue.Enabled));
         }
 
         protected override void OnPostRemove(string key, TTSVoiceState value)
diff --git a/Store/VoiceStore.cs b/Store/VoiceStore.cs
index c42644f..828695b 100644
--- a/Store/VoiceStore.cs
+++ b/Store/VoiceStore.cs
@@ -39,13 +39,19 @@ namespace HermesSocketServer.Store
 
         protected override void OnInitialAdd(string key, TTSVoice value)
         {
+            ArgumentException.ThrowIfNullOrWhiteSpace(key, nameof(key));
+            ArgumentNullException.ThrowIfNull(value, nameof(value));
             _idValidator.Check(value.Id);
             _nameValidator.Check(value.Name);
         }
 
-        protected override void OnInitialModify(string key, TTSVoice value)
+        protected override void OnInitialModify(string key, TTSVoice oldValue, TTSVoice newValue)
         {
-            _nameValidator.Check(value.Name);
+            ArgumentNullException.ThrowIfNull(newValue, nameof(newValue));
+            _idValidator.Check(newValue.Id);
+            _nameValidator.Check(newValue.Name);
+            ArgumentOutOfRangeException.ThrowIfNotEqual(oldValue.Id, newValue.Id, nameof(oldValue.Id));
+            ArgumentOutOfRangeException.ThrowIfEqual(oldValue.Name, newValue.Name, nameof(oldValue.Name));
         }
 
         protected override void OnPostRemove(string key, TTSVoice value)