diff --git a/README.md b/README.md
index 6405bc2..19b4d9e 100644
--- a/README.md
+++ b/README.md
@@ -18,10 +18,10 @@ This extension provides the `#mermaid` parser function to support the generation
 
 ## Requirements
 
-Requirements for Mermaid 3.x:
+Requirements for Mermaid 4.x:
 
-- PHP 7.0 or later
-- MediaWiki 1.33 or later
+- PHP 7.4 or later
+- MediaWiki 1.39 or later
 
 You can use an older version of Mermaid for older versions of MediaWiki and/or PHP.
 
diff --git a/composer.json b/composer.json
index b7513a0..7a147b8 100644
--- a/composer.json
+++ b/composer.json
@@ -25,7 +25,7 @@
 	},
 	"extra": {
 		"branch-alias": {
-			"dev-master": "3.x-dev"
+			"dev-master": "4.x-dev"
 		}
 	},
 	"config": {
diff --git a/extension.json b/extension.json
index 716b709..224c117 100644
--- a/extension.json
+++ b/extension.json
@@ -1,6 +1,6 @@
 {
 	"name": "Mermaid",
-	"version": "3.1.1-beta",
+	"version": "4.0.0-alpha",
 	"author": [
 			"James Hong Kong",
 			"Tyler Gibson"