diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..752676a
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+/.Build/
+/vendor/
diff --git a/composer.json b/composer.json
new file mode 100644
index 0000000..6f5d9ae
--- /dev/null
+++ b/composer.json
@@ -0,0 +1,41 @@
+{
+    "name": "werkraummedia/calendar",
+    "description": "API for extensions to create calendar",
+    "type": "typo3-cms-extension",
+    "license": "GPL-2.0-or-later",
+    "authors": [
+        {
+            "name": "Daniel Siepmann",
+            "email": "coding@daniel-siepmann.de"
+        }
+    ],
+    "config": {
+        "sort-packages": true
+    },
+    "require": {
+        "typo3/cms-core": "^10.4",
+        "typo3/cms-extbase": "^10.4"
+    },
+    "autoload": {
+        "psr-4": {
+            "WerkraumMedia\\Calendar\\": "Classes/"
+        }
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "WerkraumMedia\\Calendar\\Tests\\": "Tests/"
+        }
+    },
+    "require-dev": {
+        "jangregor/phpstan-prophecy": "^0.6.2",
+        "phpspec/prophecy-phpunit": "^2.0",
+        "phpunit/phpunit": "^9.4"
+    },
+    "extra": {
+        "typo3/cms": {
+            "cms-package-dir": "{$vendor-dir}/typo3/cms",
+            "extension-key": "calendar",
+            "web-dir": ".Build/web"
+        }
+    }
+}