diff --git a/src/main/java/net/fabricmc/loom/LoomGradleExtension.java b/src/main/java/net/fabricmc/loom/LoomGradleExtension.java
index b116bdc2..82279a06 100644
--- a/src/main/java/net/fabricmc/loom/LoomGradleExtension.java
+++ b/src/main/java/net/fabricmc/loom/LoomGradleExtension.java
@@ -83,7 +83,7 @@ public class LoomGradleExtension {
 	public boolean shareCaches = false;
 	@Deprecated
 	public String mixinConfig = null; // FORGE: Passed to Minecraft
-	public List<String> mixinConfigs = null; // FORGE: Passed to Minecraft
+	public List<String> mixinConfigs = new ArrayList<>(); // FORGE: Passed to Minecraft
 	public boolean useFabricMixin = false; // FORGE: Use Fabric Mixin for better refmap resolutions
 
 	private final ConfigurableFileCollection unmappedMods;