diff --git a/.github/workflows/master.yml b/.github/workflows/master.yml
index 815e0d9..57e6e64 100644
--- a/.github/workflows/master.yml
+++ b/.github/workflows/master.yml
@@ -18,10 +18,10 @@ jobs:
         with:
           fetch-depth: 0
 
-      - name: Setup Deno v1.25.2
+      - name: Setup Deno v1.30.1
         uses: denoland/setup-deno@v1
         with:
-          deno-version: v1.25.2
+          deno-version: v1.30.1
 
       - name: Verify formatting
         run: deno fmt mod.ts src/ --options-single-quote --options-line-width=120 --check
diff --git a/README.md b/README.md
index f08a1b5..19145e8 100644
--- a/README.md
+++ b/README.md
@@ -177,3 +177,24 @@ For convenience, an implementation of a domain version checker is available if y
 ```ts
 Switcher.checkSnapshot();
 ```
+
+# Developer Hints
+
+## VS Code - Deno Extension
+You may want to set this vscode settings if you use VSCode with Deno extension.
+
+1. Create folder/file .vscode/settings.json
+2. Add the following content:
+
+```json
+{
+    "deno.enable": true,
+    "deno.enablePaths": [],
+    "[typescript]": {
+        "editor.defaultFormatter": "denoland.vscode-deno"
+    },
+    "[typescriptreact]": {
+        "editor.defaultFormatter": "denoland.vscode-deno"
+    }
+}
+```
\ No newline at end of file