diff --git a/docfx/.vscode/launch.json b/docfx/.vscode/launch.json
index cc795dfba..a68b06d46 100644
--- a/docfx/.vscode/launch.json
+++ b/docfx/.vscode/launch.json
@@ -12,6 +12,12 @@
             "args": [
                 "copy-csproj"
             ]
+        },
+        {
+            "name": "watch-build",
+            "type": "python",
+            "request": "launch",
+            "program": "${workspaceFolder}/watch_build.py",
         }
     ]
 }
\ No newline at end of file
diff --git a/docfx/README.md b/docfx/README.md
index 93fa056cf..1d68830df 100644
--- a/docfx/README.md
+++ b/docfx/README.md
@@ -6,6 +6,8 @@
 
 * [docfx](https://dotnet.github.io/docfx/)(2系)
 * python3
+  * pip install invoke
+  * pip install watchdog
 
 # 記事の更新
 
@@ -59,3 +61,40 @@ docfx$ docfx --serve
 ```
 docfx$ docfx build
 ```
+
+## github actions
+
+`.github/workflows/docfx.yml`
+
+```yml
+name: DocFX
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: windows-2019
+    
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          fetch-depth: 1
+
+      # build docfx site to docfx/_site
+      - name: DocFX
+        shell: cmd
+        run: |
+          choco install docfx -y
+          docfx docfx\docfx.json
+
+      # push docfx/_site to gh-pages 
+      - name: Publish Documentation on GitHub Pages
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: docfx/_site
+```
diff --git a/docfx/index.md b/docfx/index.md
index 3ae250636..8403b212c 100644
--- a/docfx/index.md
+++ b/docfx/index.md
@@ -1,4 +1,3 @@
-# This is the **HOMEPAGE**.
-Refer to [Markdown](http://daringfireball.net/projects/markdown/) for how to write markdown files.
-## Quick Start Notes:
-1. Add images to the *images* folder if the file is referencing an image.
+# UniVRM Programming Document
+
+index
diff --git a/docfx/watch_build.py b/docfx/watch_build.py
new file mode 100644
index 000000000..19a98c6b5
--- /dev/null
+++ b/docfx/watch_build.py
@@ -0,0 +1,45 @@
+import sys
+import time
+import subprocess
+from watchdog.observers import Observer
+from watchdog.events import PatternMatchingEventHandler
+import pathlib
+
+HERE = pathlib.Path(__file__).absolute().parent
+
+
+class MyHandler(PatternMatchingEventHandler):
+    def __init__(self):
+        super(MyHandler, self).__init__(patterns='*.yml;*.md')
+
+    def _run_command(self):
+        subprocess.call(['docfx.exe', 'build'])
+
+    def on_moved(self, event):
+        self._run_command()
+
+    def on_created(self, event):
+        self._run_command()
+
+    def on_deleted(self, event):
+        self._run_command()
+
+    def on_modified(self, event):
+        self._run_command()
+
+
+def watch():
+    event_handler = MyHandler()
+    observer = Observer()
+    observer.schedule(event_handler, HERE, recursive=True)
+    observer.start()
+    try:
+        while True:
+            time.sleep(1)
+    except KeyboardInterrupt:
+        observer.stop()
+    observer.join()
+
+
+if __name__ == "__main__":
+    watch()