diff --git a/README.md b/README.md
index bedf7ee..816a123 100644
--- a/README.md
+++ b/README.md
@@ -317,6 +317,7 @@ Following static methods are available:
 
 ## Release History
 
+- 2.2.4 *Bugfix: wrong `const`-ness in the async generator branch (thx [Patrick Pang](https://github.com/patrickpang)).*
 - 2.2.3 *Technical release. No need to upgrade.*
 - 2.2.2 *Technical release. No need to upgrade.*
 - 2.2.1 *Technical release: new symbols namespace, explicit license (thx [Keen Yee Liau](https://github.com/kyliau)), added Greenkeeper.*
diff --git a/package-lock.json b/package-lock.json
index f40e18c..476b61d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,8 +1,42 @@
 {
   "name": "stream-chain",
-  "version": "2.2.3",
-  "lockfileVersion": 1,
+  "version": "2.2.4",
+  "lockfileVersion": 2,
   "requires": true,
+  "packages": {
+    "": {
+      "version": "2.2.4",
+      "license": "BSD-3-Clause",
+      "devDependencies": {
+        "heya-unit": "^0.3.0"
+      }
+    },
+    "node_modules/heya-ice": {
+      "version": "0.1.11",
+      "resolved": "https://registry.npmjs.org/heya-ice/-/heya-ice-0.1.11.tgz",
+      "integrity": "sha1-XW2lnGC1nHAjqDRw+26XcddwWEk=",
+      "dev": true
+    },
+    "node_modules/heya-unify": {
+      "version": "0.2.7",
+      "resolved": "https://registry.npmjs.org/heya-unify/-/heya-unify-0.2.7.tgz",
+      "integrity": "sha512-d/4NacYl52tt4ofbP7gz+YmbjLrI2jkrRxSSd1a26yXfRS1vQxmZkZ6L+O1xUsgDSwx4HCDWR5U+ZFykdoHVig==",
+      "dev": true,
+      "dependencies": {
+        "heya-ice": "^0.1.11"
+      }
+    },
+    "node_modules/heya-unit": {
+      "version": "0.3.0",
+      "resolved": "https://registry.npmjs.org/heya-unit/-/heya-unit-0.3.0.tgz",
+      "integrity": "sha1-eXR4IIyBnUxbf+NWrEwbhO67ubc=",
+      "dev": true,
+      "dependencies": {
+        "heya-ice": ">=0.1",
+        "heya-unify": ">=0.2"
+      }
+    }
+  },
   "dependencies": {
     "heya-ice": {
       "version": "0.1.11",
diff --git a/package.json b/package.json
index 34ac1db..eb3c9ed 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "stream-chain",
-  "version": "2.2.3",
+  "version": "2.2.4",
   "description": "Chain functions as transform streams.",
   "main": "index.js",
   "scripts": {