diff --git a/source/api/actions/davina_calendars.ts b/source/api/actions/davina_calendars.ts
deleted file mode 100644
index 7314b0f..0000000
--- a/source/api/actions/davina_calendars.ts
+++ /dev/null
@@ -1,68 +0,0 @@
-
-namespace _zeitbild.api
-{
-	
-	/**
-	 */
-	export function register_davina_calendars(
-		rest_subject : lib_plankton.rest_caldav.type_rest
-	) : void
-	{
-		register<
-			null,
-			(
-				null
-				|
-				Array<
-					{
-						id : int;
-						name : string;
-						access_level : string;
-					}
-				>
-			)
-		>
-		(
-			rest_subject,
-			lib_plankton.http.enum_method.get,
-			"/davina/calendars",
-			{
-				"input_schema": () => ({
-					"nullable": true,
-				}),
-				"output_schema": () => ({
-					"nullable": false,
-					"type": "boolean",
-				}),
-				"restriction": restriction_web_auth,
-				"execution": async (stuff) => {
-					const user : {id : _zeitbild.type_user_id; object : _zeitbild.type_user_object;} = await _zeitbild.api.user_from_web_auth(stuff);
-					
-					return (
-						_zeitbild.service.calendar.overview(user.id)
-						.then(
-							(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/davina_check.ts b/source/api/actions/davina_check.ts
deleted file mode 100644
index 264f4f6..0000000
--- a/source/api/actions/davina_check.ts
+++ /dev/null
@@ -1,50 +0,0 @@
-
-namespace _zeitbild.api
-{
-	
-	/**
-	 */
-	export function register_davina_check(
-		rest_subject : lib_plankton.rest_caldav.type_rest
-	) : void
-	{
-		register<
-			null,
-			null
-		>
-		(
-			rest_subject,
-			lib_plankton.http.enum_method.get,
-			"/davina/check",
-			{
-				"input_schema": () => ({
-					"nullable": true,
-				}),
-				"output_schema": () => ({
-					"nullable": true,
-				}),
-				"query_parameters": () => ([
-					{
-						"name": "username",
-						"required": true,
-						"description": "username",
-					},
-					{
-						"name": "password",
-						"required": true,
-						"description": "password",
-					},
-				]),
-				"restriction": restriction_web_auth,
-				"execution": async (stuff) => {
-					return Promise.resolve({
-						"status_code": 200,
-						"data": null,
-					});
-				},
-			}
-		);
-	}
-	
-}
-
diff --git a/source/api/actions/davina_event_get.ts b/source/api/actions/davina_event_get.ts
deleted file mode 100644
index 157c091..0000000
--- a/source/api/actions/davina_event_get.ts
+++ /dev/null
@@ -1,69 +0,0 @@
-
-namespace _zeitbild.api
-{
-	
-	/**
-	 */
-	export function register_davina_event_get(
-		rest_subject : lib_plankton.rest_caldav.type_rest
-	) : void
-	{
-		register<
-			null,
-			(null | lib_plankton.ical.type_vcalendar)
-		>(
-			rest_subject,
-			lib_plankton.http.enum_method.get,
-			"/davina/event_get",
-			{
-				"query_parameters": () => ([
-					{
-						"name": "calendar_id",
-						"required": true,
-						"description": "calendar ID",
-					},
-					{
-						"name": "event_id",
-						"required": true,
-						"description": "event ID",
-					},
-				]),
-				"output_schema": () => ({
-					"nullable": false,
-					"type": "string",
-				}),
-				"response_body_mimetype": "text/calendar",
-				"response_body_encode": (output) => Buffer.from(
-					(typeof(output) === "string")
-					?
-					output
-					:
-					(
-						lib_plankton.ical.ics_encode(output)
-						/**
-						 * @todo add event encoder function to plankton
-						 */
-						// .replace(new RegExp("[\\s\\S]*BEGIN:VEVENT([\\s\\S]*)END:VEVENT[\\s\\S]*", "m"), "BEGIN:VEVENT$1END:VEVENT")
-					)
-				),
-				"restriction": restriction_web_auth,
-				"execution": async (stuff) => {
-					const user : {id : _zeitbild.type_user_id; object : _zeitbild.type_user_object;} = await _zeitbild.api.user_from_web_auth(stuff);
-					
-					const calendar_id : int = parseInt(stuff.query_parameters["calendar_id"]);
-					const calendar_object : _zeitbild.type_calendar_object = await _zeitbild.service.calendar.get(calendar_id, user.id);
-					const event_id : int = parseInt(stuff.query_parameters["event_id"]);
-					const event_object : _zeitbild.type_event_object = await _zeitbild.service.resource.event_get(calendar_object.resource_id, event_id);
-					
-					return Promise.resolve(
-						{
-							"status_code": 200,
-							"data": _zeitbild.helpers.ical_vcalendar_from_own_event_list([event_object]),
-						}
-					);
-				}
-			}
-		);
-	}
-	
-}
diff --git a/source/api/actions/davina_event_list.ts b/source/api/actions/davina_event_list.ts
deleted file mode 100644
index 447cca4..0000000
--- a/source/api/actions/davina_event_list.ts
+++ /dev/null
@@ -1,98 +0,0 @@
-
-namespace _zeitbild.api
-{
-	
-	/**
-	 */
-	export function register_davina_event_list(
-		rest_subject : lib_plankton.rest_caldav.type_rest
-	) : void
-	{
-		register<
-			null,
-			(
-				Array<
-					{
-						event_id : (null | int);
-						event_name : string;
-					}
-				>
-				|
-				string
-			)
-		>(
-			rest_subject,
-			lib_plankton.http.enum_method.get,
-			"/davina/event_list",
-			{
-				"output_schema": () => ({
-					"type": "array",
-					"items": {
-						"nullable": false,
-						"type": "object",
-						"additionalProperties": false,
-						"properties": {
-							"event_id": {
-								"nullable": true,
-								"type": "number",
-							},
-							"event_name": {
-								"nullable": false,
-								"type": "string",
-							},
-						},
-						"required": [
-							"event_id",
-							"event_name",
-						],
-					}
-				}),
-				"restriction": restriction_web_auth,
-				"execution": async (stuff) => {
-					const user : {id : _zeitbild.type_user_id; object : _zeitbild.type_user_object;} = await _zeitbild.api.user_from_web_auth(stuff);
-					
-					/**
-					 * @todo
-					 */
-					const from : lib_plankton.pit.type_pit = 0;
-					const to : lib_plankton.pit.type_pit = 1800000000;
-					const calendar_id : int = parseInt(stuff.query_parameters["calendar_id"]);
-					
-					return (
-						_zeitbild.service.calendar.gather_events(
-							[calendar_id],
-							from,
-							to,
-							user.id
-						)
-						.then(
-							(data) => Promise.resolve(
-								{
-									"status_code": 200,
-									"data": (
-										data
-										.map(
-											(entry) => ({
-												"event_id": entry.event_id,
-												"event_name": entry.event_object.name,
-											})
-										)
-									),
-								}
-							)
-						)
-						.catch(
-							(reason) => Promise.resolve(
-								{
-									"status_code": 403,
-									"data": String(reason),
-								}
-							)
-						)
-					);
-				}
-			}
-		);
-	}
-	
-}
diff --git a/source/api/actions/export_ical.ts b/source/api/actions/export_ics.ts
similarity index 54%
rename from source/api/actions/export_ical.ts
rename to source/api/actions/export_ics.ts
index b8f68d4..efc1f28 100644
--- a/source/api/actions/export_ical.ts
+++ b/source/api/actions/export_ics.ts
@@ -4,7 +4,7 @@ namespace _zeitbild.api
 	
 	/**
 	 */
-	export function register_export_ical(
+	export function register_export_ics(
 		rest_subject : lib_plankton.rest_caldav.type_rest
 	) : void
 	{
@@ -18,9 +18,9 @@ namespace _zeitbild.api
 		>(
 			rest_subject,
 			lib_plankton.http.enum_method.get,
-			"/export/ical",
+			"/export/ics",
 			{
-				"description": "trägt Veranstaltungen aus verschiedenen Kalendern zusammen im ical-Format",
+				"description": "trägt Veranstaltungen aus verschiedenen Kalendern zusammen im ics-Format",
 				"query_parameters": () => ([
 					{
 						"name": "from",
@@ -37,11 +37,6 @@ namespace _zeitbild.api
 						"required": false,
 						"description": "comma separated",
 					},
-					{
-						"name": "auth",
-						"required": true,
-						"description": "",
-					},
 				]),
 				"output_schema": () => ({
 					"nullable": false,
@@ -55,18 +50,9 @@ namespace _zeitbild.api
 					:
 					lib_plankton.ical.ics_encode(output)
 				),
-				"restriction": restriction_none,
+				"restriction": restriction_web_auth,
 				"execution": async (stuff) => {
-					const user_id : (null | _zeitbild.type_user_id) = await (
-						session_from_stuff(stuff)
-						.then(
-							(session : {key : string; value : lib_plankton.session.type_session;}) => (
-								_zeitbild.service.user.identify(session.value.name)
-								.catch(x => Promise.resolve(null))
-							)
-						)
-						.catch(x => Promise.resolve(null))
-					);
+					const user : {id : _zeitbild.type_user_id; object : _zeitbild.type_user_object;} = await _zeitbild.api.user_from_web_auth(stuff);
 					
 					const from : lib_plankton.pit.type_pit = (
 						("from" in stuff.query_parameters)
@@ -107,57 +93,32 @@ namespace _zeitbild.api
 						null
 					);
 					
-					const auth_hash_shall : string = lib_plankton.sha256.get(
-						(stuff.query_parameters["calendar_ids"] ?? ""),
-						_zeitbild.conf.get()["misc"]["auth_salt"]
+					return (
+						_zeitbild.service.calendar.gather_events(
+							calendar_ids_wanted,
+							from,
+							to,
+							user.id
+						)
+						.then(
+							(events_extended) => Promise.resolve(
+								{
+									"status_code": 200,
+									"data": _zeitbild.helpers.icalendar_vcalendar_from_own_event_list(
+										events_extended
+									)
+								}
+							)
+						)
+						.catch(
+							(reason) => Promise.resolve(
+								{
+									"status_code": 403,
+									"data": String(reason),
+								}
+							)
+						)
 					);
-					const auth_hash_is : string = stuff.query_parameters["auth"];
-					/**
-					 * @todo remove
-					 */
-					lib_plankton.log.info(
-						"auth_hashes",
-						{
-							"shall": auth_hash_shall,
-							"is": auth_hash_is,
-						}
-					);
-					if (! (auth_hash_is === auth_hash_shall)) {
-						return Promise.resolve(
-							{
-								"status_code": 403,
-								"data": "not authorized",
-							}
-						);
-					}
-					else {
-						return (
-							_zeitbild.service.calendar.gather_events(
-								calendar_ids_wanted,
-								from,
-								to,
-								user_id
-							)
-							.then(
-								(data) => Promise.resolve(
-									{
-										"status_code": 200,
-										"data": _zeitbild.helpers.ical_vcalendar_from_own_event_list(
-											data.map(entry => entry.event_object)
-										)
-									}
-								)
-							)
-							.catch(
-								(reason) => Promise.resolve(
-									{
-										"status_code": 403,
-										"data": String(reason),
-									}
-								)
-							)
-						);
-					}
 				}
 			}
 		);
diff --git a/source/api/functions.ts b/source/api/functions.ts
index 18f7607..13c3c09 100644
--- a/source/api/functions.ts
+++ b/source/api/functions.ts
@@ -48,14 +48,7 @@ namespace _zeitbild.api
 		}
 		// export
 		{
-			_zeitbild.api.register_export_ical(rest_subject);
-		}
-		// davina
-		{
-			_zeitbild.api.register_davina_check(rest_subject);
-			_zeitbild.api.register_davina_calendars(rest_subject);
-			_zeitbild.api.register_davina_event_list(rest_subject);
-			_zeitbild.api.register_davina_event_get(rest_subject);
+			_zeitbild.api.register_export_ics(rest_subject);
 		}
 		// misc
 		{
diff --git a/source/helpers.ts b/source/helpers.ts
index 7cb1d69..b6cb9e0 100644
--- a/source/helpers.ts
+++ b/source/helpers.ts
@@ -7,7 +7,7 @@ namespace _zeitbild.helpers
 	/**
 	 * @todo timezone
 	 */
-	function ical_datetime_to_own_datetime(
+	function icalendar_datetime_to_own_datetime(
 		ical_datetime : lib_plankton.ical.type_datetime
 	) : lib_plankton.pit.type_datetime
 	{
@@ -36,7 +36,7 @@ namespace _zeitbild.helpers
 	/**
 	 * @todo timezone
 	 */
-	export function ical_dt_to_own_datetime(
+	export function icalendar_dt_to_own_datetime(
 		ical_dt: lib_plankton.ical.type_dt
 	) : lib_plankton.pit.type_datetime
 	{
@@ -61,7 +61,7 @@ namespace _zeitbild.helpers
 	/**
 	 * @todo timezone
 	 */
-	export function ical_dt_from_own_datetime(
+	export function icalendar_dt_from_own_datetime(
 		datetime : lib_plankton.pit.type_datetime
 	) : lib_plankton.ical.type_dt
 	{
@@ -92,26 +92,47 @@ namespace _zeitbild.helpers
 	
 	/**
 	 */
-	export function ical_vevent_from_own_event(
-		event_object : _zeitbild.type_event_object,
-		uid : string
+	export function icalendar_vevent_from_own_event(
+		event_extended : _zeitbild.type_event_extended,
+		index : int,
+		{
+			"stamp": stamp = "adhoc",
+		}
+		:
+		{
+			stamp ?: string;
+		}
+		=
+		{
+		}
 	) : lib_plankton.ical.type_vevent
 	{
 		return {
-			"uid": uid,
-			"dtstamp": ical_dt_from_own_datetime(event_object.begin).value,
-			"dtstart": ical_dt_from_own_datetime(event_object.begin),
+			"uid": lib_plankton.string.coin(
+				"zeitbild_{{stamp}}_{{id}}",
+				{
+					"stamp": stamp,
+					// "id": event_extended.event_id.toFixed(0),
+					"id": index.toFixed(0),
+				}
+			),
+			"dtstamp": icalendar_dt_from_own_datetime(event_extended.event_object.begin).value,
+			"dtstart": icalendar_dt_from_own_datetime(event_extended.event_object.begin),
 			"dtend": (
-				(event_object.end === null)
+				(event_extended.event_object.end === null)
 				?
 				undefined
 				:
-				ical_dt_from_own_datetime(event_object.end)
+				icalendar_dt_from_own_datetime(event_extended.event_object.end)
 			),
-			"location": (event_object.location ?? undefined),
-			"summary": event_object.name,
-			"url": (event_object.link ?? undefined),
-			"description": (event_object.description ?? undefined),
+			"location": (event_extended.event_object.location ?? undefined),
+			"summary": event_extended.event_object.name,
+			"url": (event_extended.event_object.link ?? undefined),
+			"description": (event_extended.event_object.description ?? undefined),
+			/**
+			 * @todo transform name
+			 */
+			"categories": [event_extended.calendar_name],
 		};
 	}
 	
@@ -119,8 +140,8 @@ namespace _zeitbild.helpers
 	/**
 	 * @todo assign better uids
 	 */
-	export function ical_vcalendar_from_own_event_list(
-		events : Array<_zeitbild.type_event_object>
+	export function icalendar_vcalendar_from_own_event_list(
+		events_extended : Array<_zeitbild.type_event_extended>
 	) : lib_plankton.ical.type_vcalendar
 	{
 		const pit_now : lib_plankton.pit.type_pit = lib_plankton.pit.now();
@@ -137,18 +158,15 @@ namespace _zeitbild.helpers
 			"version": "2.0",
 			"prodid": "",
 			"vevents": (
-				events
+				events_extended
 				.map<lib_plankton.ical.type_vevent>(
-					(entry, index) => ical_vevent_from_own_event(
-						entry,
-						lib_plankton.string.coin(
-							"zeitbild_{{stamp}}_{{index}}",
-							{
-								"stamp": stamp,
-								"index": index.toFixed(0)
-							}
-						)
-					),
+					(event_extended, index) => icalendar_vevent_from_own_event(
+						event_extended,
+						index,
+						{
+							"stamp": stamp,
+						}
+					)
 				)
 			),
 			"method": "PUBLISH",
diff --git a/source/services/calendar.ts b/source/services/calendar.ts
index f2a21dc..2055515 100644
--- a/source/services/calendar.ts
+++ b/source/services/calendar.ts
@@ -389,11 +389,11 @@ namespace _zeitbild.service.calendar
 											:
 											"???"
 										),
-										"begin": _zeitbild.helpers.ical_dt_to_own_datetime(vevent.dtstart),
+										"begin": _zeitbild.helpers.icalendar_dt_to_own_datetime(vevent.dtstart),
 										"end": (
 											(vevent.dtend !== undefined)
 											?
-											_zeitbild.helpers.ical_dt_to_own_datetime(vevent.dtend)
+											_zeitbild.helpers.icalendar_dt_to_own_datetime(vevent.dtend)
 											:
 											null
 										),
@@ -454,19 +454,6 @@ namespace _zeitbild.service.calendar
 	}
 	
 	
-	/**
-	 */
-	type type_gather_events_result = Array<
-		{
-			calendar_id : _zeitbild.type_calendar_id;
-			calendar_name : string;
-			access_level : _zeitbild.enum_access_level;
-			event_id : (null | _zeitbild.type_local_resource_event_id);
-			event_object : _zeitbild.type_event_object;
-		}
-	>;
-	
-	
 	/**
 	 */
 	export async function gather_events(
@@ -474,7 +461,7 @@ namespace _zeitbild.service.calendar
 		from_pit : lib_plankton.pit.type_pit,
 		to_pit : lib_plankton.pit.type_pit,
 		user_id : (null | _zeitbild.type_user_id)
-	) : Promise<type_gather_events_result>
+	) : Promise<Array<_zeitbild.type_event_extended>>
 	{
 		const calendar_ids_allowed : Array<_zeitbild.type_calendar_id> = (
 			(await overview(user_id))
@@ -496,7 +483,7 @@ namespace _zeitbild.service.calendar
 			)
 		);
 		calendar_ids.sort();
-		return lib_plankton.cache.get_complex<any, type_gather_events_result>(
+		return lib_plankton.cache.get_complex<any, Array<_zeitbild.type_event_extended>>(
 			_zeitbild.cache_regular,
 			"gather_events",
 			{
diff --git a/source/types.ts b/source/types.ts
index d27d7c2..181082f 100644
--- a/source/types.ts
+++ b/source/types.ts
@@ -119,5 +119,16 @@ namespace _zeitbild
 		};
 		resource_id : type_resource_id;
 	};
+
+	
+	/**
+	 */
+	export type type_event_extended = {
+		calendar_id : type_calendar_id;
+		calendar_name : string;
+		access_level : enum_access_level;
+		event_id : (null | type_local_resource_event_id);
+		event_object : type_event_object;
+	};
 	
 }
diff --git a/tools/makefile b/tools/makefile
index 31d77f3..d6c2da1 100644
--- a/tools/makefile
+++ b/tools/makefile
@@ -76,11 +76,7 @@ ${dir_temp}/zeitbild-unlinked.js: \
 		${dir_source}/api/actions/calendar_event_change.ts \
 		${dir_source}/api/actions/calendar_event_remove.ts \
 		${dir_source}/api/actions/events.ts \
-		${dir_source}/api/actions/export_ical.ts \
-		${dir_source}/api/actions/davina_check.ts \
-		${dir_source}/api/actions/davina_calendars.ts \
-		${dir_source}/api/actions/davina_event_list.ts \
-		${dir_source}/api/actions/davina_event_get.ts \
+		${dir_source}/api/actions/export_ics.ts \
 		${dir_source}/api/functions.ts \
 		${dir_source}/main.ts
 	@ ${cmd_log} "compile …"