diff --git a/CHANGELOG.md b/CHANGELOG.md
index 53a325b..32789e6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,3 @@
 ### What's New
 
-* Updated Dark Matter.
\ No newline at end of file
+* Fixed startup crash and default linkers in 1.21.
\ No newline at end of file
diff --git a/build.gradle b/build.gradle
index 448786f..9f50bab 100644
--- a/build.gradle
+++ b/build.gradle
@@ -148,6 +148,7 @@ publishMods {
         projectId = "sc4Mu9Zu"
         accessToken = providers.environmentVariable("MODRINTH_TOKEN")
         minecraftVersions.add("${project.minecraft_version}")
+        minecraftVersions.add("1.21")
 
         requires("fabric-api")
         embeds("dark-matter")
@@ -156,6 +157,7 @@ publishMods {
         projectId = "622736"
         accessToken = providers.environmentVariable("CURSEFORGE_TOKEN")
         minecraftVersions.add("${project.minecraft_version}")
+        minecraftVersions.add("1.21")
 
         requires("fabric-api")
         embeds("dark-matter")
diff --git a/gradle.properties b/gradle.properties
index 0bdd252..d6c2fae 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -5,6 +5,6 @@ org.gradle.jvmargs=-Xmx1G
 minecraft_version=1.20.6
 yarn_mappings=1.20.6+build.3
 # Mod Properties
-mod_version=5.4.4
+mod_version=5.4.5
 maven_group=com.github.vini2003.linkart
 archives_base_name=linkart
diff --git a/src/main/java/com/github/vini2003/linkart/Linkart.java b/src/main/java/com/github/vini2003/linkart/Linkart.java
index 746263a..371ce0e 100644
--- a/src/main/java/com/github/vini2003/linkart/Linkart.java
+++ b/src/main/java/com/github/vini2003/linkart/Linkart.java
@@ -26,7 +26,7 @@ public class Linkart implements ModInitializer {
     public static final ConfigManager<LinkartConfiguration> CONFIG_MANAGER = ConfigManager.of(LinkartConfiguration.class, ID, LinkartConfiguration::new)
             .exceptionHandler((e, stage, path) -> LOGGER.error("Failed to {} {}", stage.name().toLowerCase(), FabricLoader.getInstance().getGameDir().relativize(path)));
     private static LinkartConfiguration CONFIG;
-    public static final TagKey<Item> LINKERS = TagKey.of(itemKey(), new Identifier(ID, "linkers"));
+    public static final TagKey<Item> LINKERS = TagKey.of(itemKey(), Identifier.of(ID, "linkers"));
 
     static {
         loadConfig();
diff --git a/src/main/resources/data/linkart/tags/item/linkers.json b/src/main/resources/data/linkart/tags/item/linkers.json
new file mode 100644
index 0000000..5cae040
--- /dev/null
+++ b/src/main/resources/data/linkart/tags/item/linkers.json
@@ -0,0 +1,6 @@
+{
+  "replace": false,
+  "values": [
+    "minecraft:chain"
+  ]
+}
\ No newline at end of file