diff --git a/.github/workflows/prod-web-deploy.yml b/.github/workflows/prod-web-deploy.yml
index 7b950ed..ec539ee 100644
--- a/.github/workflows/prod-web-deploy.yml
+++ b/.github/workflows/prod-web-deploy.yml
@@ -18,7 +18,8 @@ jobs:
 
       - uses: actions/setup-node@v7
         with:
-          node-version: 20
+          # the site's lockfile resolves mermaid 12 (via @docusaurus/theme-mermaid), which needs node >= 22.12
+          node-version: 22
           cache: yarn
           cache-dependency-path: website/yarn.lock
 
diff --git a/.github/workflows/test-web-deploy.yml b/.github/workflows/test-web-deploy.yml
index 64df0d3..8e5aa9f 100644
--- a/.github/workflows/test-web-deploy.yml
+++ b/.github/workflows/test-web-deploy.yml
@@ -18,7 +18,8 @@ jobs:
 
       - uses: actions/setup-node@v7
         with:
-          node-version: 20
+          # the site's lockfile resolves mermaid 12 (via @docusaurus/theme-mermaid), which needs node >= 22.12
+          node-version: 22
           cache: yarn
           cache-dependency-path: website/yarn.lock
 
diff --git a/website/package.json b/website/package.json
index 3c098a2..78c027c 100644
--- a/website/package.json
+++ b/website/package.json
@@ -67,7 +67,7 @@
     ]
   },
   "engines": {
-    "node": ">=20.0"
+    "node": ">=22.12"
   },
   "license": "MIT"
 }