diff --git a/data/example.json b/data/example.json
index c07cbbc..5ea2f80 100644
--- a/data/example.json
+++ b/data/example.json
@@ -23,13 +23,15 @@
 		{
 			"id": 1,
 			"name": "house",
-			"public": false,
-			"members": [
-				{
-					"user_id": 1,
-					"role": "editor"
-				}
-			],
+			"access": {
+				"default_level": "none",
+				"attributed": [
+					{
+						"user_id": 1,
+						"level": "edit"
+					}
+				]
+			},
 			"resource": {
 				"kind": "local",
 				"data": {
@@ -86,17 +88,19 @@
 		{
 			"id": 2,
 			"name": "turf",
-			"public": false,
-			"members": [
-				{
-					"user_id": 1,
-					"role": "viewer"
-				},
-				{
-					"user_id": 2,
-					"role": "editor"
-				}
-			],
+			"access": {
+				"default_level": "none",
+				"attributed": [
+					{
+						"user_id": 1,
+						"level": "view"
+					},
+					{
+						"user_id": 2,
+						"level": "edit"
+					}
+				]
+			},
 			"resource": {
 				"kind": "local",
 				"data": {
@@ -138,21 +142,23 @@
 		{
 			"id": 3,
 			"name": "town",
-			"public": true,
-			"members": [
-				{
-					"user_id": 1,
-					"role": "viewer"
-				},
-				{
-					"user_id": 2,
-					"role": "viewer"
-				},
-				{
-					"user_id": 3,
-					"role": "editor"
-				}
-			],
+			"access": {
+				"default_level": "none",
+				"attributed": [
+					{
+						"user_id": 1,
+						"level": "view"
+					},
+					{
+						"user_id": 2,
+						"level": "view"
+					},
+					{
+						"user_id": 3,
+						"level": "edit"
+					}
+				]
+			},
 			"resource": {
 				"kind": "local",
 				"data": {
diff --git a/source/api/actions/calendar_add.ts b/source/api/actions/calendar_add.ts
new file mode 100644
index 0000000..7718c1a
--- /dev/null
+++ b/source/api/actions/calendar_add.ts
@@ -0,0 +1,50 @@
+
+namespace _zeitbild.api
+{
+	
+	/**
+	 */
+	export function register_calendar_list(
+		rest_subject : lib_plankton.rest.type_rest
+	) : void
+	{
+		register<
+			{
+				name : string;
+				public : boolean;
+				members : Array<
+					{
+						user_id : user_id;
+						role : role;
+					}
+				>;
+				resource_id : resource_id;
+			},
+			int
+		>(
+			rest_subject,
+			lib_plankton.http.enum_method.post,
+			"/calendar/add",
+			{
+				"description": "erstellt einen Kalender",
+				"output_schema": () => ({
+					"nullable": true,
+					"type": "integer",
+				}),
+				"restriction": restriction_logged_in,
+				"execution": async (stuff) => {
+					return (
+						_zeitbild.service.calendar.overview(user_id)
+						.then(
+							data => Promise.resolve({
+								"status_code": 200,
+								"data": data,
+							})
+						)
+					);
+				}
+			}
+		);
+	}
+	
+}
diff --git a/source/api/actions/calendar_list.ts b/source/api/actions/calendar_list.ts
index 9dc4d21..494da2e 100644
--- a/source/api/actions/calendar_list.ts
+++ b/source/api/actions/calendar_list.ts
@@ -12,10 +12,9 @@ namespace _zeitbild.api
 			null,
 			Array<
 				{
-					id : _zeitbild.type.calendar_id;
+					id : int;
 					name : string;
-					public : boolean;
-					role : (null | _zeitbild.type.role);
+					access_level : string;
 				}
 			>
 		>(
@@ -41,13 +40,10 @@ namespace _zeitbild.api
 								"type": "string",
 								"nullable": false,
 							},
-							"public": {
-								"type": "boolean",
-								"nullable": false,
-							},
-							"role": {
+							"access_level": {
 								"type": "string",
 								"nullable": true,
+								"enum": ["none", "edit", "view", "admin"]
 							},
 						},
 						"required": [
@@ -66,7 +62,19 @@ namespace _zeitbild.api
 					return (
 						_zeitbild.service.calendar.overview(user_id)
 						.then(
-							data => Promise.resolve({
+							(data_raw) => Promise.resolve(
+								data_raw
+								.map(
+									(entry) => ({
+										"id": entry.id,
+										"name": entry.name,
+										"access_level": _zeitbild.value_object.access_level.to_string(entry.access_level),
+									})
+								)
+							)
+						)
+						.then(
+							(data) => Promise.resolve({
 								"status_code": 200,
 								"data": data,
 							})
diff --git a/source/api/actions/events.ts b/source/api/actions/events.ts
index 37725c7..a5661c4 100644
--- a/source/api/actions/events.ts
+++ b/source/api/actions/events.ts
@@ -142,9 +142,8 @@ namespace _zeitbild.api
 								)
 							)
 						)
-						// @ts-ignore
-						.toSorted()
 					);
+					calendar_ids.sort();
 					const data = await _zeitbild.service.calendar.gather_events(
 						calendar_ids,
 						from,
diff --git a/source/main.ts b/source/main.ts
index cc5846c..aedad07 100644
--- a/source/main.ts
+++ b/source/main.ts
@@ -14,13 +14,15 @@ type type_data = {
 		{
 			id : int;
 			name : string;
-			public : boolean;
-			members : Array<
-				{
-					user_id : int;
-					role : _zeitbild.type.role;
-				}
-			>;
+			access : {
+				default_level : ("none" | "view" | "edit" | "admin");
+				attributed : Array<
+					{
+						user_id : int;
+						level : ("none" | "view" | "edit" | "admin");
+					}
+				>;
+			};
 			resource : _zeitbild.type.resource_object;
 		}
 	>;
@@ -47,11 +49,12 @@ async function data_init(
 		"calendar": {},
 	};
 	for await (const user_raw of data.users) {
+		const user_object : _zeitbild.type.user_object = {
+			"name": user_raw.name,
+			"email_address": user_raw.email_address,
+		};
 		const user_id : _zeitbild.type.user_id = await _zeitbild.service.user.add(
-			{
-				"name": user_raw.name,
-				"email_address": user_raw.email_address,
-			}
+			user_object
 		);
 		await _zeitbild.service.auth_internal.set(
 			user_raw.name,
@@ -60,24 +63,35 @@ async function data_init(
 		track.user[user_raw.id] = user_id;
 	}
 	for await (const calendar_raw of data.calendars) {
+		const resource_object : _zeitbild.type.resource_object = calendar_raw.resource;
 		const resource_id : _zeitbild.type.resource_id = await _zeitbild.service.resource.add(
-			calendar_raw.resource
+			resource_object
 		);
-		const calendar_id : _zeitbild.type.calendar_id = await _zeitbild.service.calendar.add(
-			{
-				"name": calendar_raw.name,
-				"public": calendar_raw.public,
-				"members": (
-					calendar_raw.members
-					.map(
-						(member_raw) => ({
-							"user_id": track.user[member_raw.user_id],
-							"role": member_raw.role,
-						})
+		const calendar_object : _zeitbild.type.calendar_object = {
+			"name": calendar_raw.name,
+			"access": {
+				"default_level": _zeitbild.value_object.access_level.from_string(calendar_raw.access.default_level),
+				"attributed": lib_plankton.map.hashmap.implementation_map(
+					lib_plankton.map.hashmap.make(
+						x => x.toFixed(0),
+						{
+							"pairs": (
+								calendar_raw.access.attributed
+								.map(
+									(entry) => ({
+										"key": track.user[entry.user_id],
+										"value": _zeitbild.value_object.access_level.from_string(entry.level),
+									})
+								)
+							),
+						}
 					)
 				),
-				"resource_id": resource_id,
-			}
+			},
+			"resource_id": resource_id,
+		};
+		const calendar_id : _zeitbild.type.calendar_id = await _zeitbild.service.calendar.add(
+			calendar_object
 		);
 		track.calendar[calendar_raw.id] = calendar_id;
 	}
diff --git a/source/repositories/calendar.ts b/source/repositories/calendar.ts
index af7561e..df4943d 100644
--- a/source/repositories/calendar.ts
+++ b/source/repositories/calendar.ts
@@ -9,7 +9,7 @@ namespace _zeitbild.repository.calendar
 			string,
 			any
 		>;
-		member_rows : Array<
+		access_attributed_rows : Array<
 			Record<
 				string,
 				any
@@ -35,7 +35,7 @@ namespace _zeitbild.repository.calendar
 	
 	/**
 	 */
-	var _member_chest : (
+	var _access_attributed_chest : (
 		null
 		|
 		lib_plankton.storage.type_chest<
@@ -77,7 +77,7 @@ namespace _zeitbild.repository.calendar
 	
 	/**
 	 */
-	function get_member_chest(
+	function get_access_attributed_chest(
 	) : lib_plankton.storage.type_chest<
 		Array<any>,
 		Record<string, any>,
@@ -86,11 +86,11 @@ namespace _zeitbild.repository.calendar
 		Record<string, any>
 	>
 	{
-		if (_member_chest === null) {
-			_member_chest = lib_plankton.storage.sql_table_common.chest(
+		if (_access_attributed_chest === null) {
+			_access_attributed_chest = lib_plankton.storage.sql_table_common.chest(
 				{
 					"database_implementation": _zeitbild.database.get_implementation(),
-					"table_name": "calendar_members",
+					"table_name": "calendar_access_attributed",
 					"key_names": ["calendar_id","user_id"],
 				}
 			);
@@ -98,7 +98,41 @@ namespace _zeitbild.repository.calendar
 		else {
 			// do nothing
 		}	
-		return _member_chest;
+		return _access_attributed_chest;
+	}
+	
+	
+	/**
+	 */
+	function encode_access_level(
+		access_level : _zeitbild.type.enum_access_level
+	) : int
+	{
+		return (
+			[
+				_zeitbild.type.enum_access_level.none,
+				_zeitbild.type.enum_access_level.view,
+				_zeitbild.type.enum_access_level.edit,
+				_zeitbild.type.enum_access_level.admin,
+			].indexOf(access_level)
+		);
+	}
+	
+	
+	/**
+	 */
+	function decode_access_level(
+		access_level_encoded : int
+	) : _zeitbild.type.enum_access_level
+	{
+		return (
+			[
+				_zeitbild.type.enum_access_level.none,
+				_zeitbild.type.enum_access_level.view,
+				_zeitbild.type.enum_access_level.edit,
+				_zeitbild.type.enum_access_level.admin,
+			][access_level_encoded]
+		);
 	}
 	
 	
@@ -111,16 +145,16 @@ namespace _zeitbild.repository.calendar
 		return {
 			"core_row": {
 				"name": object.name,
-				"public": object.public,
+				"access_level_default": encode_access_level(object.access.default_level),
 				"resource_id": object.resource_id,
 			},
-			"member_rows": (
-				object.members
+			"access_attributed_rows": (
+				lib_plankton.map.dump(object.access.attributed)
 				.map(
-					(member) => ({
+					({"key": user_id, "value": level}) => ({
 						// "calendar_id": calendar_id,
-						"user_id": member.user_id,
-						"role": member.role,
+						"user_id": user_id,
+						"level": encode_access_level(level),
 					})
 				)
 			),
@@ -136,17 +170,19 @@ namespace _zeitbild.repository.calendar
 	{
 		return {
 			"name": dispersal.core_row["name"],
-			"public": dispersal.core_row["public"],
-			"members": (
-				dispersal.member_rows
-				.map(
-					(member_row) => ({
-						"calendar_id": member_row["calendar_id"],
-						"user_id": member_row["user_id"],
-						"role": member_row["role"],
-					})
-				)
-			),
+			"access": {
+				"default_level": decode_access_level(dispersal.core_row["access_level_default"]),
+				"attributed": Object.fromEntries(
+					dispersal.access_attributed_rows
+					.map(
+						(access_attributed_row) => ([
+							// "calendar_id": access_attributed_row["calendar_id"],
+							access_attributed_row["user_id"],
+							decode_access_level(access_attributed_row["level"]),
+						])
+					)
+				),
+			},
 			"resource_id": dispersal.core_row["resource_id"],
 		};
 	}
@@ -213,7 +249,7 @@ namespace _zeitbild.repository.calendar
 			get_core_store().read(id)
 			.then(
 				(core_row) => (
-					get_member_chest().search(
+					get_access_attributed_chest().search(
 						{
 							"expression": "(calendar_id = $calendar_id)",
 							"arguments": {
@@ -222,10 +258,10 @@ namespace _zeitbild.repository.calendar
 						}
 					)
 					.then(
-						(member_rows) => Promise.resolve<type_dispersal>(
+						(access_attributed_rows) => Promise.resolve<type_dispersal>(
 							{
 								"core_row": core_row,
-								"member_rows": member_rows,
+								"access_attributed_rows": access_attributed_rows,
 							}
 						)
 					)
@@ -257,11 +293,11 @@ namespace _zeitbild.repository.calendar
 					.then<_zeitbild.type.calendar_id>(
 						(calendar_id) => (
 							Promise.all(
-								dispersal.member_rows
+								dispersal.access_attributed_rows
 								.map(
-									(member_row) => get_member_chest().write(
-										[calendar_id, member_row["user_id"]],
-										{"role": member_row["role"]}
+									(access_attributed_row) => get_access_attributed_chest().write(
+										[calendar_id, access_attributed_row["user_id"]],
+										{"level": access_attributed_row["level"]}
 									)
 								)
 							)
@@ -277,51 +313,43 @@ namespace _zeitbild.repository.calendar
 	
 	
 	/**
-	 * @todo sort for role, public and id
 	 */
-	export function overview(
+	export async function overview(
 		user_id : _zeitbild.type.user_id
 	) : Promise<
 		Array<
 			{
 				id : _zeitbild.type.calendar_id;
 				name : string;
-				public : boolean;
-				role : (null | _zeitbild.type.role);
+				access_level : _zeitbild.type.enum_access_level;
 			}
 		>
 	>
 	{
 		return (
-			_zeitbild.database.get_implementation().query_free_get(
-				{
-					"template": "SELECT x.id AS id, x.name AS name, x.public AS public, MAX(y.role) AS role FROM calendars AS x LEFT OUTER JOIN calendar_members AS y ON (x.id = y.calendar_id) WHERE (x.public OR (y.user_id = $user_id)) GROUP BY x.id;",
-					"arguments": {
-						"user_id": user_id,
+			lib_plankton.file.read("sql/calendar_overview.sql")
+			.then(
+				(template) => _zeitbild.database.get_implementation().query_free_get(
+					{
+						"template": template,
+						"arguments": {
+							"user_id": user_id,
+						}
 					}
-				}
+				)
 			)
 			.then(
 				(rows) => Promise.resolve(
-					rows.map(
+					rows
+					.map(
 						(row) => ({
 							"id": row["id"],
 							"name": row["name"],
-							"public": (row["public"] === 1),
-							"role": row["role"],
+							"access_level": decode_access_level(row["access_level"]),
 						})
 					)
 				)
 			)
-			/*
-			.then(
-				(entries) => Promise.resolve(
-					entries.toSorted(
-						(x, y) => (x
-					)
-				)
-			)
-			 */
 		)
 	}
 }
diff --git a/source/repositories/sql/calendar_overview.sql b/source/repositories/sql/calendar_overview.sql
new file mode 100644
index 0000000..7fb2808
--- /dev/null
+++ b/source/repositories/sql/calendar_overview.sql
@@ -0,0 +1,20 @@
+SELECT
+	x.id AS id,
+	x.name AS name,
+	(
+		CASE
+			WHEN MAX(y.level) IS NULL THEN x.access_level_default
+			ELSE MAX(y.level)
+		END
+	) AS access_level
+FROM
+	calendars AS x
+	LEFT OUTER JOIN calendar_access_attributed AS y ON ((x.id = y.calendar_id) AND (y.user_id = $user_id))
+GROUP BY
+	x.id
+HAVING
+	(access_level > 0)
+ORDER BY
+	access_level,
+	id
+;
diff --git a/source/services/calendar.ts b/source/services/calendar.ts
index 48d3da2..3866d8b 100644
--- a/source/services/calendar.ts
+++ b/source/services/calendar.ts
@@ -50,8 +50,7 @@ namespace _zeitbild.service.calendar
 			{
 				id : _zeitbild.type.calendar_id;
 				name : string;
-				public : boolean;
-				role : (null | _zeitbild.type.role);
+				access_level : _zeitbild.type.enum_access_level;
 			}
 		>
 	>
diff --git a/source/types.ts b/source/types.ts
index 54c48db..c73fcd7 100644
--- a/source/types.ts
+++ b/source/types.ts
@@ -6,13 +6,12 @@ namespace _zeitbild.type
 	
 	/**
 	 */
-	export type role = (
-		"admin"
-		|
-		"editor"
-		|
-		"viewer"
-	);
+	export enum enum_access_level {
+		none,
+		view,
+		edit,
+		admin
+	}
 	
 	
 	/**
@@ -91,13 +90,13 @@ namespace _zeitbild.type
 	 */
 	export type calendar_object = {
 		name : string;
-		public : boolean;
-		members : Array<
-			{
-				user_id : user_id;
-				role : role;
-			}
-		>;
+		access : {
+			default_level : enum_access_level;
+			attributed : lib_plankton.map.type_map<
+				user_id,
+				enum_access_level
+			>;
+		};
 		resource_id : resource_id;
 	};
 	
diff --git a/source/value_objects/access_level.ts b/source/value_objects/access_level.ts
new file mode 100644
index 0000000..6c97d58
--- /dev/null
+++ b/source/value_objects/access_level.ts
@@ -0,0 +1,55 @@
+
+/**
+ */
+namespace _zeitbild.value_object.access_level
+{
+	
+	/**
+	 */
+	export function to_string(
+		access_level : _zeitbild.type.enum_access_level
+	) : string
+	{
+		switch (access_level) {
+			case _zeitbild.type.enum_access_level.none: {return "none";}
+			case _zeitbild.type.enum_access_level.view: {return "view";}
+			case _zeitbild.type.enum_access_level.edit: {return "edit";}
+			case _zeitbild.type.enum_access_level.admin: {return "admin";}
+			default: {throw (new Error("invalid access level: " + String(access_level)));}
+		}
+	}
+	
+	
+	/**
+	 */
+	export function from_string(
+		access_level_ : string
+	) : _zeitbild.type.enum_access_level
+	{
+		switch (access_level_) {
+			case "none": {return _zeitbild.type.enum_access_level.none;}
+			case "view": {return _zeitbild.type.enum_access_level.view;}
+			case "edit": {return _zeitbild.type.enum_access_level.edit;}
+			case "admin": {return _zeitbild.type.enum_access_level.admin;}
+			default: {throw (new Error("invalid encoded access level: " + String(access_level_)));}
+		}
+	}
+	
+	
+	/**
+	 */
+	export function order(
+		x : _zeitbild.type.enum_access_level,
+		y : _zeitbild.type.enum_access_level
+	) : boolean
+	{
+		const list : Array<_zeitbild.type.enum_access_level> = [
+			_zeitbild.type.enum_access_level.none,
+			_zeitbild.type.enum_access_level.view,
+			_zeitbild.type.enum_access_level.edit,
+			_zeitbild.type.enum_access_level.admin,
+		];
+		return (list.indexOf(x) <= list.indexOf(y));
+	}
+	
+}
diff --git a/tools/makefile b/tools/makefile
index 24533e2..8e61c4e 100644
--- a/tools/makefile
+++ b/tools/makefile
@@ -18,11 +18,14 @@ cmd_tsc := ${dir_tools}/typescript/node_modules/.bin/tsc
 ## rules
 
 .PHONY: default
-default: ${dir_build}/zeitbild node_modules
+default: sql ${dir_build}/zeitbild node_modules
 
-.PHONY: node_modules
-node_modules:
-	@ cd ${dir_build} && npm install sqlite3 bcrypt
+.PHONY: sql
+sql: \
+		$(wildcard ${dir_source}/repositories/sql/*)
+	@ ${cmd_log} "sql …"
+	@ ${cmd_mkdir} ${dir_build}/sql
+	@ ${cmd_cp} -r -u $^ ${dir_build}/sql/
 
 ${dir_temp}/conf.ts: \
 		${dir_source}/conf.ts.tpl \
@@ -37,6 +40,7 @@ ${dir_temp}/zeitbild-unlinked.js: \
 		${dir_source}/database.ts \
 		${dir_source}/auth.ts \
 		${dir_source}/types.ts \
+		${dir_source}/value_objects/access_level.ts \
 		${dir_source}/repositories/auth_internal.ts \
 		${dir_source}/repositories/user.ts \
 		${dir_source}/repositories/resource.ts \
@@ -72,3 +76,7 @@ ${dir_build}/zeitbild: \
 	@ ${cmd_mkdir} $(dir $@)
 	@ ${cmd_cat} $^ > $@
 	@ ${cmd_chmod} +x $@
+
+.PHONY: node_modules
+node_modules:
+	@ cd ${dir_build} && npm install sqlite3 bcrypt