diff --git a/build.gradle.kts b/build.gradle.kts
index 5fee651..2df4c11 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -7,6 +7,9 @@ plugins {
 
 dependencies {
     modImplementation("io.gitlab.jfronny.libjf:libjf-config-core-v1:${prop("libjf_version")}")
+    include(modImplementation(fabricApi.module("fabric-message-api-v1", prop("fabric_version")))!!)
+    include(modImplementation(fabricApi.module("fabric-command-api-v2", prop("fabric_version")))!!)
+    modImplementation(fabricApi.module("fabric-networking-api-v1", prop("fabric_version")))
 
     // Dev env
     modLocalRuntime("io.gitlab.jfronny.libjf:libjf-config-ui-tiny-v1:${prop("libjf_version")}")
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/ChatTransform.java b/src/client/java/io/gitlab/jfronny/chattransform/ChatTransform.java
deleted file mode 100644
index dc9c301..0000000
--- a/src/client/java/io/gitlab/jfronny/chattransform/ChatTransform.java
+++ /dev/null
@@ -1,13 +0,0 @@
-package io.gitlab.jfronny.chattransform;
-
-import io.gitlab.jfronny.commons.log.Logger;
-import net.fabricmc.api.ClientModInitializer;
-
-public class ChatTransform implements ClientModInitializer {
-    public static final Logger LOG = Logger.forName("chat-transform");
-
-    @Override
-    public void onInitializeClient() {
-        LOG.info("Loaded chat-transform");
-    }
-}
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/ITextFieldWidget.java b/src/client/java/io/gitlab/jfronny/chattransform/client/ITextFieldWidget.java
similarity index 69%
rename from src/client/java/io/gitlab/jfronny/chattransform/ITextFieldWidget.java
rename to src/client/java/io/gitlab/jfronny/chattransform/client/ITextFieldWidget.java
index 3690188..d893074 100644
--- a/src/client/java/io/gitlab/jfronny/chattransform/ITextFieldWidget.java
+++ b/src/client/java/io/gitlab/jfronny/chattransform/client/ITextFieldWidget.java
@@ -1,4 +1,4 @@
-package io.gitlab.jfronny.chattransform;
+package io.gitlab.jfronny.chattransform.client;
 
 public interface ITextFieldWidget {
     void chattransform$activate();
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/Substitution.java b/src/client/java/io/gitlab/jfronny/chattransform/client/Substitution.java
similarity index 84%
rename from src/client/java/io/gitlab/jfronny/chattransform/Substitution.java
rename to src/client/java/io/gitlab/jfronny/chattransform/client/Substitution.java
index 82cecc7..a52b4a3 100644
--- a/src/client/java/io/gitlab/jfronny/chattransform/Substitution.java
+++ b/src/client/java/io/gitlab/jfronny/chattransform/client/Substitution.java
@@ -1,4 +1,4 @@
-package io.gitlab.jfronny.chattransform;
+package io.gitlab.jfronny.chattransform.client;
 
 public record Substitution(int start, int end, long time) {
     public Substitution(int start, int end) {
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/TransformStart.java b/src/client/java/io/gitlab/jfronny/chattransform/client/TransformStart.java
similarity index 96%
rename from src/client/java/io/gitlab/jfronny/chattransform/TransformStart.java
rename to src/client/java/io/gitlab/jfronny/chattransform/client/TransformStart.java
index 2987f83..ca23da3 100644
--- a/src/client/java/io/gitlab/jfronny/chattransform/TransformStart.java
+++ b/src/client/java/io/gitlab/jfronny/chattransform/client/TransformStart.java
@@ -1,4 +1,4 @@
-package io.gitlab.jfronny.chattransform;
+package io.gitlab.jfronny.chattransform.client;
 
 public class TransformStart {
     private boolean available = false;
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/client/mixin/ChatScreenMixin.java b/src/client/java/io/gitlab/jfronny/chattransform/client/mixin/ChatScreenMixin.java
new file mode 100644
index 0000000..a7c9315
--- /dev/null
+++ b/src/client/java/io/gitlab/jfronny/chattransform/client/mixin/ChatScreenMixin.java
@@ -0,0 +1,27 @@
+package io.gitlab.jfronny.chattransform.client.mixin;
+
+import io.gitlab.jfronny.chattransform.*;
+import io.gitlab.jfronny.chattransform.client.ITextFieldWidget;
+import net.minecraft.client.gui.screen.ChatScreen;
+import net.minecraft.client.gui.widget.TextFieldWidget;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.*;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(ChatScreen.class)
+public abstract class ChatScreenMixin {
+    @Shadow protected TextFieldWidget chatField;
+
+    @Inject(at = @At("RETURN"), method = "init()V")
+    void init(CallbackInfo ci) {
+        if (Cfg.Client.mode == Cfg.Mode.Live) ((ITextFieldWidget) chatField).chattransform$activate();
+    }
+
+    @Redirect(method = "keyPressed(III)Z", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/gui/widget/TextFieldWidget;getText()Ljava/lang/String;"))
+    String finalizeTransforms(TextFieldWidget instance) {
+        String text = ((ITextFieldWidget) chatField).chattransform$finalize();
+        if (Cfg.Client.mode == Cfg.Mode.OnSend) text = ChatTransform.transform(text);
+        return text;
+    }
+}
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/mixin/TextFieldWidgetMixin.java b/src/client/java/io/gitlab/jfronny/chattransform/client/mixin/TextFieldWidgetMixin.java
similarity index 98%
rename from src/client/java/io/gitlab/jfronny/chattransform/mixin/TextFieldWidgetMixin.java
rename to src/client/java/io/gitlab/jfronny/chattransform/client/mixin/TextFieldWidgetMixin.java
index 9e73e45..eb55f5a 100644
--- a/src/client/java/io/gitlab/jfronny/chattransform/mixin/TextFieldWidgetMixin.java
+++ b/src/client/java/io/gitlab/jfronny/chattransform/client/mixin/TextFieldWidgetMixin.java
@@ -1,8 +1,8 @@
-package io.gitlab.jfronny.chattransform.mixin;
+package io.gitlab.jfronny.chattransform.client.mixin;
 
 import io.gitlab.jfronny.chattransform.*;
+import io.gitlab.jfronny.chattransform.client.*;
 import net.minecraft.client.font.TextRenderer;
-import net.minecraft.client.gui.DrawableHelper;
 import net.minecraft.client.gui.screen.Screen;
 import net.minecraft.client.gui.widget.ClickableWidget;
 import net.minecraft.client.gui.widget.TextFieldWidget;
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/mixin/ChatScreenMixin.java b/src/client/java/io/gitlab/jfronny/chattransform/mixin/ChatScreenMixin.java
deleted file mode 100644
index 9dea623..0000000
--- a/src/client/java/io/gitlab/jfronny/chattransform/mixin/ChatScreenMixin.java
+++ /dev/null
@@ -1,44 +0,0 @@
-package io.gitlab.jfronny.chattransform.mixin;
-
-import io.gitlab.jfronny.chattransform.Cfg;
-import io.gitlab.jfronny.chattransform.ITextFieldWidget;
-import net.minecraft.client.gui.screen.ChatScreen;
-import net.minecraft.client.gui.widget.TextFieldWidget;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.*;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-
-import java.util.*;
-import java.util.regex.Pattern;
-import java.util.stream.Collectors;
-
-@Mixin(ChatScreen.class)
-public abstract class ChatScreenMixin {
-    @Shadow protected TextFieldWidget chatField;
-
-    @Inject(at = @At("RETURN"), method = "init()V")
-    void init(CallbackInfo ci) {
-        if (Cfg.mode == Cfg.Mode.Live) ((ITextFieldWidget) chatField).chattransform$activate();
-    }
-
-    @Redirect(method = "keyPressed(III)Z", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/gui/widget/TextFieldWidget;getText()Ljava/lang/String;"))
-    String finalizeTransforms(TextFieldWidget instance) {
-        String str = ((ITextFieldWidget) chatField).chattransform$finalize();
-        if (Cfg.mode == Cfg.Mode.OnSend) {
-            for (Map.Entry<String, String> e : Cfg.substitutions
-                    .entrySet()
-                    .stream()
-                    .collect(Collectors.groupingBy(s -> s.getKey().length()))
-                    .entrySet()
-                    .stream()
-                    .sorted(Map.Entry.<Integer, List<Map.Entry<String, String>>>comparingByKey().reversed())
-                    .map(Map.Entry::getValue)
-                    .flatMap(Collection::stream)
-                    .toList()) {
-                str = str.replaceAll(Pattern.quote(e.getKey()), e.getValue());
-            }
-        }
-        return str;
-    }
-}
diff --git a/src/client/resources/assets/chat-transform/lang/en_us.json b/src/client/resources/assets/chat-transform/lang/en_us.json
index 953c8f6..dde0aca 100644
--- a/src/client/resources/assets/chat-transform/lang/en_us.json
+++ b/src/client/resources/assets/chat-transform/lang/en_us.json
@@ -2,10 +2,20 @@
   "chat-transform.jfconfig.title": "Chat-Transform",
   "chat-transform.jfconfig.substitutions": "Substitutions",
   "chat-transform.jfconfig.substitutions.tooltip": "The substitutions to perform on text sent in the chat. See the presets for examples",
-  "chat-transform.jfconfig.mode": "Mode",
-  "chat-transform.jfconfig.mode.tooltip": "When to perform replacements",
-  "chat-transform.jfconfig.visualize": "Visualize",
-  "chat-transform.jfconfig.visualize.tooltip": "Visualize transformations as you type in live mode",
+  "chat-transform.jfconfig.client.title": "Client Settings",
+  "chat-transform.jfconfig.client.mode": "Mode",
+  "chat-transform.jfconfig.client.mode.tooltip": "When to perform replacements",
   "chat-transform.jfconfig.enum.Mode.Live": "Live",
-  "chat-transform.jfconfig.enum.Mode.OnSend": "On Send"
+  "chat-transform.jfconfig.enum.Mode.OnSend": "On Send",
+  "chat-transform.jfconfig.client.visualize": "Visualize",
+  "chat-transform.jfconfig.client.visualize.tooltip": "Visualize transformations as you type in live mode",
+  "chat-transform.jfconfig.server.title": "Server Settings",
+  "chat-transform.jfconfig.server.messageOnFirstConnect": "Message on first connect",
+  "chat-transform.jfconfig.server.messageOnFirstConnect.tooltip": "Whether to send a chat message to players about chat-transform when they first connect",
+  "chat-transform.jfconfig.server.playerStates": "Player States",
+  "chat-transform.jfconfig.server.playerStates.tooltip": "For which players messages should be transformed",
+  "chat-transform.jfconfig.server.playerConfigurable": "Player Configurable",
+  "chat-transform.jfconfig.server.playerConfigurable.tooltip": "Whether players should be able to toggle chat transformation",
+  "chat-transform.jfconfig.server.defaultEnable": "Default Enable",
+  "chat-transform.jfconfig.server.defaultEnable.tooltip": "Whether players' chat should be transformed by default"
 }
\ No newline at end of file
diff --git a/src/client/resources/chat-transform.client.mixins.json b/src/client/resources/chat-transform.client.mixins.json
index 426ff91..987e296 100644
--- a/src/client/resources/chat-transform.client.mixins.json
+++ b/src/client/resources/chat-transform.client.mixins.json
@@ -1,7 +1,7 @@
 {
   "required": true,
   "minVersion": "0.8",
-  "package": "io.gitlab.jfronny.chattransform.mixin",
+  "package": "io.gitlab.jfronny.chattransform.client.mixin",
   "compatibilityLevel": "JAVA_17",
   "client": [
     "ChatScreenMixin",
diff --git a/src/main/java/io/gitlab/jfronny/chattransform/Cfg.java b/src/main/java/io/gitlab/jfronny/chattransform/Cfg.java
new file mode 100644
index 0000000..10fe8c0
--- /dev/null
+++ b/src/main/java/io/gitlab/jfronny/chattransform/Cfg.java
@@ -0,0 +1,78 @@
+package io.gitlab.jfronny.chattransform;
+
+import io.gitlab.jfronny.commons.serialize.gson.api.v1.Ignore;
+import io.gitlab.jfronny.libjf.config.api.v1.*;
+
+import java.util.*;
+
+@JfConfig
+public class Cfg {
+    @Entry public static Map<String, String> substitutions = Map.of();
+
+    @Category
+    public static class Client {
+        @Entry public static Mode mode = Mode.Live;
+        @Entry public static boolean visualize = true;
+    }
+
+    @Category
+    public static class Server {
+        @Entry public static boolean messageOnFirstConnect = true;
+        @Entry public static Map<String, Boolean> playerStates = new HashMap<>();
+        @Entry public static boolean playerConfigurable = true;
+        @Entry public static boolean defaultEnable = true;
+    }
+
+    public enum Mode {
+        Live, OnSend
+    }
+
+    @Preset
+    public static void owo() {
+        substitutions = new LinkedHashMap<>();
+        substitutions.put("r", "w");
+        substitutions.put("l", "w");
+        substitutions.put("R", "W");
+        substitutions.put("L", "W");
+        substitutions.put("no", "nu");
+        substitutions.put("has", "haz");
+        substitutions.put("have", "haz");
+        substitutions.put("you", "uu");
+        substitutions.put("the ", "da ");
+        substitutions.put("The ", "Da ");
+    }
+
+    @Preset
+    public static void demonstrationPurposesOnly() {
+        substitutions = new LinkedHashMap<>();
+        substitutions.put("chat-transform", "Chat-Transform (this mod)");
+        substitutions.put(":tm:", "™");
+        substitutions.put("(c)", "©");
+    }
+
+    @Ignore private static final char[] consonants = "bcdfghjklmprstwz".toCharArray();
+
+    @Preset
+    public static void katakana() {
+        substitutions = new LinkedHashMap<>();
+        substitutions.put("-", "ー");
+        for (char c : consonants) {
+            substitutions.put("" + c + c, "ッ" + c);
+        }
+        substitutions.put("nn", "ン");
+        JapaneseMap.fromTable(JapaneseMap.katakanaTable, substitutions::put);
+        System.out.println("katakana " + substitutions);
+    }
+
+    @Preset
+    public static void hiragana() {
+        substitutions = new LinkedHashMap<>();
+        substitutions.put("-", "ー");
+        for (char c : consonants) {
+            substitutions.put("" + c + c, "っ" + c);
+        }
+        substitutions.put("nn", "ん");
+        JapaneseMap.fromTable(JapaneseMap.hiraganaTable, substitutions::put);
+        System.out.println("hiragana " + substitutions);
+    }
+}
diff --git a/src/main/java/io/gitlab/jfronny/chattransform/ChatTransform.java b/src/main/java/io/gitlab/jfronny/chattransform/ChatTransform.java
new file mode 100644
index 0000000..73cb843
--- /dev/null
+++ b/src/main/java/io/gitlab/jfronny/chattransform/ChatTransform.java
@@ -0,0 +1,28 @@
+package io.gitlab.jfronny.chattransform;
+
+import io.gitlab.jfronny.commons.log.Logger;
+
+import java.util.*;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+public class ChatTransform {
+    public static final String MOD_ID = "chat-transform";
+    public static final Logger LOG = Logger.forName(MOD_ID);
+
+    public static String transform(String text) {
+        for (Map.Entry<String, String> e : Cfg.substitutions
+                .entrySet()
+                .stream()
+                .collect(Collectors.groupingBy(s -> s.getKey().length()))
+                .entrySet()
+                .stream()
+                .sorted(Map.Entry.<Integer, List<Map.Entry<String, String>>>comparingByKey().reversed())
+                .map(Map.Entry::getValue)
+                .flatMap(Collection::stream)
+                .toList()) {
+            text = text.replaceAll(Pattern.quote(e.getKey()), e.getValue());
+        }
+        return text;
+    }
+}
diff --git a/src/client/java/io/gitlab/jfronny/chattransform/Cfg.java b/src/main/java/io/gitlab/jfronny/chattransform/JapaneseMap.java
similarity index 56%
rename from src/client/java/io/gitlab/jfronny/chattransform/Cfg.java
rename to src/main/java/io/gitlab/jfronny/chattransform/JapaneseMap.java
index d849d9b..d7ffb54 100644
--- a/src/client/java/io/gitlab/jfronny/chattransform/Cfg.java
+++ b/src/main/java/io/gitlab/jfronny/chattransform/JapaneseMap.java
@@ -1,45 +1,9 @@
 package io.gitlab.jfronny.chattransform;
 
-import io.gitlab.jfronny.commons.serialize.gson.api.v1.Ignore;
-import io.gitlab.jfronny.libjf.config.api.v1.*;
+import java.util.function.BiConsumer;
 
-import java.util.LinkedHashMap;
-import java.util.Map;
-
-@JfConfig
-public class Cfg {
-    @Entry public static Map<String, String> substitutions = Map.of();
-    @Entry public static Mode mode = Mode.Live;
-    @Entry public static boolean visualize = true;
-
-    public enum Mode {
-        Live, OnSend
-    }
-
-    @Preset
-    public static void owo() {
-        substitutions = new LinkedHashMap<>();
-        substitutions.put("r", "w");
-        substitutions.put("l", "w");
-        substitutions.put("R", "W");
-        substitutions.put("L", "W");
-        substitutions.put("no", "nu");
-        substitutions.put("has", "haz");
-        substitutions.put("have", "haz");
-        substitutions.put("you", "uu");
-        substitutions.put("the ", "da ");
-        substitutions.put("The ", "Da ");
-    }
-
-    @Preset
-    public static void demonstrationPurposesOnly() {
-        substitutions = new LinkedHashMap<>();
-        substitutions.put("chat-transform", "Chat-Transform (this mod)");
-        substitutions.put(":tm:", "™");
-        substitutions.put("(c)", "©");
-    }
-
-    @Ignore private static final String katakanaTable = """
+public class JapaneseMap {
+    public static final String katakanaTable = """
             	a	i	u	e	o	n
             	ア	イ	ウ	エ	オ	ン
             x	ァ	ィ	ゥ	ェ	ォ
@@ -72,7 +36,7 @@ public class Cfg {
             py	ピャ		ピュ		ピョ
             v			ゔ""";
 
-    @Ignore private static final String hiraganaTable = """
+    public static final String hiraganaTable = """
             	a	i	u	e	o	n
             	あ	い	う	え	お	ん
             x	ぁ	ぃ	ぅ	ぇ	ぉ
@@ -105,9 +69,7 @@ public class Cfg {
             py	ぴゃ		ぴゅ		ぴょ
             v			ゔ""";
 
-    @Ignore private static final char[] consonants = "bcdfghjklmprstwz".toCharArray();
-
-    private static void fromTable(String table) {
+    public static void fromTable(String table, BiConsumer<String, String> target) {
         String[] rows = table.split("\n");
         String[] colNames = rows[0].split("\t");
         for (int i = 1; i < rows.length; i++) {
@@ -120,34 +82,10 @@ public class Cfg {
                 String[] kanas = kana.split("/");
                 for (String singleKana : kanas) {
                     if (!singleKana.isEmpty()) {
-                        substitutions.put(value, singleKana);
+                        target.accept(value, singleKana);
                     }
                 }
             }
         }
     }
-
-    @Preset
-    public static void katakana() {
-        substitutions = new LinkedHashMap<>();
-        substitutions.put("-", "ー");
-        for (char c : consonants) {
-            substitutions.put("" + c + c, "ッ" + c);
-        }
-        substitutions.put("nn", "ン");
-        fromTable(katakanaTable);
-        System.out.println("katakana " + substitutions);
-    }
-
-    @Preset
-    public static void hiragana() {
-        substitutions = new LinkedHashMap<>();
-        substitutions.put("-", "ー");
-        for (char c : consonants) {
-            substitutions.put("" + c + c, "っ" + c);
-        }
-        substitutions.put("nn", "ん");
-        fromTable(hiraganaTable);
-        System.out.println("hiragana " + substitutions);
-    }
 }
diff --git a/src/main/java/io/gitlab/jfronny/chattransform/server/ChatTransformServer.java b/src/main/java/io/gitlab/jfronny/chattransform/server/ChatTransformServer.java
new file mode 100644
index 0000000..bbc7b2a
--- /dev/null
+++ b/src/main/java/io/gitlab/jfronny/chattransform/server/ChatTransformServer.java
@@ -0,0 +1,143 @@
+package io.gitlab.jfronny.chattransform.server;
+
+import com.mojang.brigadier.Command;
+import io.gitlab.jfronny.chattransform.Cfg;
+import io.gitlab.jfronny.chattransform.ChatTransform;
+import io.gitlab.jfronny.libjf.config.api.v1.ConfigInstance;
+import net.fabricmc.api.DedicatedServerModInitializer;
+import net.fabricmc.fabric.api.command.v2.CommandRegistrationCallback;
+import net.fabricmc.fabric.api.message.v1.ServerMessageDecoratorEvent;
+import net.fabricmc.fabric.api.networking.v1.ServerLoginConnectionEvents;
+import net.fabricmc.fabric.api.networking.v1.ServerPlayConnectionEvents;
+import net.minecraft.network.packet.s2c.play.ChatMessageS2CPacket;
+import net.minecraft.network.packet.s2c.play.GameMessageS2CPacket;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.text.*;
+import org.spongepowered.asm.mixin.Mutable;
+
+import java.util.Arrays;
+import java.util.Objects;
+import java.util.concurrent.CompletableFuture;
+
+import static net.minecraft.server.command.CommandManager.*;
+
+public class ChatTransformServer implements DedicatedServerModInitializer {
+    public static final ConfigInstance CONFIG_INSTANCE = Objects.requireNonNull(ConfigInstance.get(ChatTransform.MOD_ID));
+
+    @Override
+    public void onInitializeServer() {
+        CommandRegistrationCallback.EVENT.register((dispatcher, registryAccess, environment) -> {
+            var root = literal(ChatTransform.MOD_ID).executes(context -> {
+                context.getSource().sendMessage(Text.literal(ChatTransform.MOD_ID + " is " + (get(context.getSource().getPlayer()) ? "enabled" : "disabled") + " for you."));
+                return Command.SINGLE_SUCCESS;
+            });
+            root.then(literal("opt-in").requires(src -> Cfg.Server.playerConfigurable).executes(context -> {
+                if (context.getSource().getPlayer() == null) {
+                    context.getSource().sendError(Text.literal("You are not a player."));
+                    return Command.SINGLE_SUCCESS;
+                }
+                if (get(context.getSource().getPlayer())) {
+                    context.getSource().sendError(Text.literal("You are already opted in to using chat-transform."));
+                    return Command.SINGLE_SUCCESS;
+                }
+                set(context.getSource().getPlayer(), true);
+                context.getSource().sendMessage(Text.literal("Toggled " + ChatTransform.MOD_ID + " on"));
+                return Command.SINGLE_SUCCESS;
+            }));
+            root.then(literal("opt-out").requires(src -> Cfg.Server.playerConfigurable).executes(context -> {
+                if (context.getSource().getPlayer() == null) {
+                    context.getSource().sendError(Text.literal("You are not a player."));
+                    return Command.SINGLE_SUCCESS;
+                }
+                if (!get(context.getSource().getPlayer())) {
+                    context.getSource().sendError(Text.literal("You are already opted out of using chat-transform."));
+                    return Command.SINGLE_SUCCESS;
+                }
+                set(context.getSource().getPlayer(), false);
+                context.getSource().sendMessage(Text.literal("Toggled " + ChatTransform.MOD_ID + " off"));
+                return Command.SINGLE_SUCCESS;
+            }));
+            root.then(literal("reset").requires(src -> Cfg.Server.playerConfigurable).executes(context -> {
+                if (context.getSource().getPlayer() == null) {
+                    context.getSource().sendError(Text.literal("You are not a player."));
+                    return Command.SINGLE_SUCCESS;
+                }
+                reset(context.getSource().getPlayer());
+                context.getSource().sendMessage(Text.literal("Reset " + ChatTransform.MOD_ID + " to " + (Cfg.Server.defaultEnable ? "on" : "off")));
+                return Command.SINGLE_SUCCESS;
+            }));
+            root.then(literal("reset-all").requires(src -> src.hasPermissionLevel(4)).executes(context -> {
+                Cfg.Server.playerStates.clear();
+                CONFIG_INSTANCE.write();
+                context.getSource().sendMessage(Text.literal("Reset all player states"));
+                return Command.SINGLE_SUCCESS;
+            }));
+            dispatcher.register(root);
+        });
+
+        ServerPlayConnectionEvents.JOIN.register((handler, sender, server) -> {
+            if (Cfg.Server.messageOnFirstConnect && !has(handler.getPlayer())) {
+                set(handler.getPlayer(), Cfg.Server.defaultEnable);
+                MutableText text = Text.literal("This server uses " + ChatTransform.MOD_ID + " to transform messages you send.");
+                if (Cfg.Server.playerConfigurable) {
+                    text.append(" To turn it " + (Cfg.Server.defaultEnable ? "off" : "on") + ", use ");
+                    String command = "/" + ChatTransform.MOD_ID + " opt-" + (Cfg.Server.defaultEnable ? "out" : "in");
+                    text.append(Text.literal(command)
+                            .styled(s -> s.withClickEvent(new ClickEvent(ClickEvent.Action.RUN_COMMAND, command)))
+                    );
+                    text.append(".");
+                }
+                handler.getPlayer().sendMessage(text);
+            }
+        });
+
+        ServerMessageDecoratorEvent.EVENT.register(ServerMessageDecoratorEvent.CONTENT_PHASE, (sender, message) -> {
+            return CompletableFuture.completedFuture(sender != null && get(sender) ? transform(message) : message);
+        });
+    }
+
+    private boolean has(ServerPlayerEntity player) {
+        return Cfg.Server.playerStates.containsKey(player.getUuidAsString());
+    }
+
+    private boolean get(ServerPlayerEntity player) {
+        return Cfg.Server.playerStates.computeIfAbsent(player.getUuidAsString(), k -> Cfg.Server.defaultEnable);
+    }
+
+    private void set(ServerPlayerEntity player, boolean value) {
+        Cfg.Server.playerStates.put(player.getUuidAsString(), value);
+        CONFIG_INSTANCE.write();
+    }
+
+    private void reset(ServerPlayerEntity player) {
+        Cfg.Server.playerStates.remove(player.getUuidAsString());
+        CONFIG_INSTANCE.write();
+    }
+
+    private Text transform(Text source) {
+        MutableText result = MutableText.of(transform(source.getContent()))
+                .setStyle(source.getStyle());
+        for (Text sibling : source.getSiblings()) {
+            result.append(transform(sibling));
+        }
+        return result;
+    }
+
+    private TextContent transform(TextContent source) {
+        if (source instanceof TranslatableTextContent tx) {
+            Object[] args = tx.getArgs();
+            args = Arrays.copyOf(args, args.length);
+            for (int i = 0; i < args.length; i++) {
+                if (args[i] instanceof Text tx1) args[i] = transform(tx1);
+                else if (args[i] instanceof TextContent tx1) args[i] = transform(tx1);
+                else if (args[i] instanceof String tx1) args[i] = ChatTransform.transform(tx1);
+                else args[i] = args[i];
+            }
+            return new TranslatableTextContent(tx.getKey(), ChatTransform.transform(tx.getFallback()), args);
+        } else if (source instanceof LiteralTextContent tx) {
+            return new LiteralTextContent(ChatTransform.transform(tx.string()));
+        } else {
+            return source;
+        }
+    }
+}
diff --git a/src/main/resources/fabric.mod.json b/src/main/resources/fabric.mod.json
index 4c66686..c367c23 100644
--- a/src/main/resources/fabric.mod.json
+++ b/src/main/resources/fabric.mod.json
@@ -13,9 +13,9 @@
   },
   "license": "MIT",
   "icon": "assets/chat-transform/icon.png",
-  "environment": "client",
+  "environment": "*",
   "entrypoints": {
-    "client": ["io.gitlab.jfronny.chattransform.ChatTransform"],
+    "server": ["io.gitlab.jfronny.chattransform.server.ChatTransformServer"],
     "libjf:config": ["io.gitlab.jfronny.chattransform.JFC_Cfg"]
   },
   "mixins": [