diff --git a/ext/spec_1.json b/ext/spec_1.json
new file mode 100644
index 0000000..50e1a60
--- /dev/null
+++ b/ext/spec_1.json
@@ -0,0 +1,80 @@
+{
+  "$ref": "#/definitions/event",
+  "definitions": {
+    "specversion": {
+      "type": "string",
+      "minLength": 1,
+      "const": "1.0"
+    },
+    "datacontenttype": {
+      "type": "string"
+    },
+    "data": {
+      "type": ["object", "string"]
+    },
+    "data_base64": {
+      "type": "string"
+    },
+    "event": {
+      "properties": {
+        "specversion": {
+          "$ref": "#/definitions/specversion"
+        },
+        "datacontenttype": {
+          "$ref": "#/definitions/datacontenttype"
+        },
+        "data": {
+          "$ref": "#/definitions/data"
+        },
+        "data_base64": {
+          "$ref": "#/definitions/data_base64"
+        },
+        "id": {
+          "$ref": "#/definitions/id"
+        },
+        "time": {
+          "$ref": "#/definitions/time"
+        },
+        "dataschema": {
+          "$ref": "#/definitions/dataschema"
+        },
+        "subject": {
+          "$ref": "#/definitions/subject"
+        },
+        "type": {
+          "$ref": "#/definitions/type"
+        },
+        "source": {
+          "$ref": "#/definitions/source"
+        }
+      },
+      "required": ["specversion", "id", "type", "source"],
+      "type": "object"
+    },
+    "id": {
+      "type": "string",
+      "minLength": 1
+    },
+    "time": {
+      "format": "date-time",
+      "type": "string"
+    },
+    "dataschema": {
+      "type": "string",
+      "format": "uri"
+    },
+    "subject": {
+      "type": "string",
+      "minLength": 1
+    },
+    "type": {
+      "type": "string",
+      "minLength": 1
+    },
+    "source": {
+      "format": "uri-reference",
+      "type": "string"
+    }
+  },
+  "type": "object"
+}