diff --git a/source/localization/de.json b/source/localization/de.json
index ba0fc67..8ae818d 100644
--- a/source/localization/de.json
+++ b/source/localization/de.json
@@ -16,6 +16,7 @@
 	"help.args.show_schema": "nur das hmdl-JSON-Schema zur Standard-Ausgabe schreiben und beenden",
 	"help.args.expose_full_order": "nur den Pfad zur Datenbank-Datei zur Standard-Ausgabe schreiben und beenden (nützlich für Fehlersuche)",
 	"help.args.show_version": "nur die Version zur Standard-Ausgabe schreiben und beenden",
+	"help.args.verbosity": "Schwellwert für Log-Ausgaben",
 	"checks.file_state.exists": "Datei existiert (soll aber nicht)",
 	"checks.file_state.missing": "Datei existiert nicht (soll aber)",
 	"checks.file_state.timestamp_implausible": "Datei ist scheinbar aus der Zukunft",
diff --git a/source/localization/en.json b/source/localization/en.json
index 73698f4..318dcc5 100644
--- a/source/localization/en.json
+++ b/source/localization/en.json
@@ -16,6 +16,7 @@
 	"help.args.show_schema": "print the hmdl JSON schema to stdout and exit",
 	"help.args.expose_full_order": "only print the extended order to stdout and exit (useful for debugging)",
 	"help.args.show_version": "only print the version to stdout and exit",
+	"help.args.verbosity": "threshold for log outputs",
 	"checks.file_state.exists": "file exists (but shall not)",
 	"checks.file_state.missing": "file does not exist (but shall)",
 	"checks.file_state.timestamp_implausible": "file is apparently from the future",
diff --git a/source/logic/base.ts b/source/logic/base.ts
index 5978791..25d5c1a 100644
--- a/source/logic/base.ts
+++ b/source/logic/base.ts
@@ -102,6 +102,15 @@ namespace _heimdall
 	};
 	
 	
+	/**
+	 */
+	export function get_current_timestamp(
+	) : int
+	{
+		return Math.floor(Date.now() / 1000);
+	}
+	
+	
 	/**
 	 * converts a condition to a human readable string
 	 */
diff --git a/source/logic/check_kinds/file_state.ts b/source/logic/check_kinds/file_state.ts
index a3c6f2f..86cf1a2 100644
--- a/source/logic/check_kinds/file_state.ts
+++ b/source/logic/check_kinds/file_state.ts
@@ -90,7 +90,7 @@ namespace _heimdall.check_kinds.file_state
 	) : any
 	{
 		const version : string = (
-			(! ("exist_mode" in node)
+			(! ("exist_mode" in node))
 			? "v1"
 			: "v2"
 		);
@@ -115,6 +115,7 @@ namespace _heimdall.check_kinds.file_state
 						node
 					);
 					return {
+						"path": node["path"],
 						"exist_mode": node_["exist"],
 						"exist_critical": node_["strict"],
 						"age_threshold_concerning": (
@@ -171,7 +172,153 @@ namespace _heimdall.check_kinds.file_state
 		parameters
 	) : Promise<_heimdall.type_result>
 	{
-		return Promise.reject<_heimdall.type_result>(new Error("not implemented"));
+		const nm_fs = require("fs");
+		
+		let condition : _heimdall.enum_condition = _heimdall.enum_condition.ok;
+		let faults : Array<string> = [];
+		let data : Record<string, any> = {};
+		
+		let exists : boolean;
+		let stats : {
+			ctime : float;
+			size : int;
+		};
+		await new Promise<void>(
+			(resolve, reject) => {
+				nm_fs.stat(
+					parameters["path"],
+					{
+						"bigint": false,
+					},
+					(err, stats_) => {
+						if (err) {
+							exists = false;
+							stats = null;
+							resolve(undefined);
+						}
+						else {
+							exists = true;
+							stats = stats_;
+							resolve(undefined);
+						}
+					}
+				);
+			}
+		);
+		if (! parameters["exist_mode"]) {
+			if (exists) {
+				condition = (
+					parameters["exist_critical"]
+					? _heimdall.enum_condition.concerning
+					: _heimdall.enum_condition.critical
+				);
+				faults.push(lib_plankton.translate.get("checks.file_state.exists"));
+			}
+			else {
+				// do nothing
+			}
+		}
+		else {
+			if (! exists) {
+				condition = (
+					parameters["exist_critical"]
+					? _heimdall.enum_condition.concerning
+					: _heimdall.enum_condition.critical
+				);
+				faults.push(lib_plankton.translate.get("checks.file_state.missing"));
+			}
+			else {
+				// age
+				{
+					const timestamp_this : int = _heimdall.get_current_timestamp();
+					const timestamp_that : int = Math.floor(stats.ctime);
+					const age : int = (timestamp_this - timestamp_that);
+					if (age < 0) {
+						condition = _heimdall.enum_condition.critical;
+						faults.push(lib_plankton.translate.get("checks.file_state.timestamp_implausible"));
+					}
+					else {
+						if (
+							(parameters["age_threshold_critical"] !== null)
+							&&
+							(age > parameters["age_threshold_critical"])
+						) {
+							condition = _heimdall.enum_condition.critical;
+							faults.push(lib_plankton.translate.get("checks.file_state.too_old"));
+						}
+						else {
+							if (
+								(parameters["age_threshold_concerning"] !== null)
+								&&
+								(age > parameters["age_threshold_concerning"])
+							) {
+								condition = _heimdall.enum_condition.critical;
+								faults.push(lib_plankton.translate.get("checks.file_state.too_old"));
+							}
+							else {
+								// do nothing
+							}
+						}
+					}
+					data = Object.assign(
+						data,
+						{
+							"timestamp_of_checking_instance": timestamp_this,
+							"timestamp_of_file": timestamp_that,
+							"age_value_in_seconds": age,
+							"age_threshold_in_seconds_concerning": parameters["age_threshold_concerning"],
+							"age_threshold_in_seconds_critical": parameters["age_threshold_critical"],
+						}
+					);
+				}
+				// size
+				{
+					const size : int = stats.size;
+					if (size < 0) {
+						condition = _heimdall.enum_condition.critical;
+						faults.push(lib_plankton.translate.get("checks.file_state.size_implausible"));
+					}
+					else {
+						if (
+							(parameters["size_threshold_critical"] !== null)
+							&&
+							(size > parameters["size_threshold_critical"])
+						) {
+							condition = _heimdall.enum_condition.critical;
+							faults.push(lib_plankton.translate.get("checks.file_state.too_big"));
+						}
+						else {
+							if (
+								(parameters["size_threshold_concerning"] !== null)
+								&&
+								(size > parameters["size_threshold_concerning"])
+							) {
+								condition = _heimdall.enum_condition.critical;
+								faults.push(lib_plankton.translate.get("checks.file_state.too_big"));
+							}
+							else {
+								// do nothing
+							}
+						}
+					}
+					data = Object.assign(
+						data,
+						{
+							"size_value_in_bytes": size,
+							"size_threshold_in_bytes": parameters["size_threshold"],
+						}
+					);
+				}
+			}
+		}
+		return {
+			"condition": condition,
+			"info": {
+				"path": parameters["path"],
+				"faults": faults,
+				"data": data,
+			}
+		};
 	}
 	
 	
diff --git a/source/logic/main.ts b/source/logic/main.ts
index 6987790..1e2c564 100644
--- a/source/logic/main.ts
+++ b/source/logic/main.ts
@@ -151,7 +151,12 @@ async function main(
 						"indicators_long": ["send-ok-notifications"],
 						"indicators_short": ["y"],
 					},
-					"info": lib_plankton.translate.get("help.args.send_ok_notifications"),
+					"info": lib_plankton.translate.get(
+						"help.args.send_ok_notifications",
+						{
+							"condition_name": lib_plankton.translate.get("conditions.ok"),
+						}
+					),
 				}
 			),
 			"language": new lib_plankton.args.class_argument(
@@ -182,6 +187,20 @@ async function main(
 					"info": lib_plankton.translate.get("help.args.time_to_live"),
 				}
 			),
+			"verbosity": new lib_plankton.args.class_argument(
+				{
+					"name": "verbosity",
+					"type": lib_plankton.args.enum_type.integer,
+					"kind": lib_plankton.args.enum_kind.volatile,
+					"mode": lib_plankton.args.enum_mode.replace,
+					"default": 1,
+					"parameters": {
+						"indicators_long": ["verbosity"],
+						"indicators_short": ["v"],
+					},
+					"info": lib_plankton.translate.get("help.args.verbosity"),
+				}
+			),
 		}
 	);
 	const args : Record<string, any> = arg_handler.read(
@@ -189,6 +208,22 @@ async function main(
 		process.argv.slice(2).join(" ")
 	);
 	
+	// setup logging
+	lib_plankton.log.conf_push(
+		[
+			new lib_plankton.log.class_channel_minlevel(
+				new lib_plankton.log.class_channel_stdout(),
+				[
+					lib_plankton.log.enum_level.debug,
+					lib_plankton.log.enum_level.info,
+					lib_plankton.log.enum_level.notice,
+					lib_plankton.log.enum_level.warning,
+					lib_plankton.log.enum_level.error,
+				][Math.min(4, args["verbosity"])]
+			),
+		]
+	);
+	
 	// exec
 	if (args.show_help) {
 		process.stdout.write(
@@ -211,6 +246,7 @@ async function main(
 			};
 			const check_kind_implementations : Record<string, _heimdall.check_kinds.type_check_kind> = {
 				"http_request": _heimdall.check_kinds.http_request.check_kind_implementation(),
+				"file_state": _heimdall.check_kinds.file_state.check_kind_implementation(),
 			};
 			if (args["show_schema"]) {
 				process.stdout.write(
@@ -308,6 +344,13 @@ async function main(
 										// do nothing
 									}
 									else {
+										let old_item_state : (null | _heimdall.type_item_state);
+										
+										const last_notification_timestamp : (null | int) = await _heimdall.state_repository.get_last_notification_timestamp(
+											database_path,
+											check.name
+										);
+										
 										const rows : Array<
 											{
 												timestamp : int;
@@ -319,29 +362,19 @@ async function main(
 											check.name,
 											(check.threshold + 1),
 										);
-										
-										// TODO: type
-										let old_item_state : (null | _heimdall.type_item_state);
-
-										const last_notification_timestamp : (null | int) = await _heimdall.state_repository.get_last_notification_timestamp(
-											database_path,
-											check.name
-										);
-										
 										if (rows.length <= 0) {
 											old_item_state = null;
 										}
 										else {
-											last_notification_timestamp = null;
 											let count : int = 1;
 											rows.slice(1).some(
 												(row) => {
 													if (row.condition === rows[0].condition) {
 														count += 1;
-														return false;
+														return true;
 													}
 													else {
-														return true;
+														return false;
 													}
 												}
 											);
@@ -351,17 +384,6 @@ async function main(
 											else {
 												// do nothing
 											}
-											rows.some(
-												(row) => {
-													if (row.notification_sent) {
-														last_notification_timestamp = row.timestamp;
-														return true;
-													}
-													else {
-														return false;
-													}
-												}
-											);
 											old_item_state = {
 												"timestamp": rows[0].timestamp,
 												"condition": rows[0].condition,
@@ -369,7 +391,7 @@ async function main(
 												"last_notification_timestamp": last_notification_timestamp,
 											}
 											
-											const timestamp : int = Math.floor(Date.now() / 1000);
+											const timestamp : int = _heimdall.get_current_timestamp();
 											const due : boolean = (
 												(old_item_state === null)
 												||
diff --git a/source/logic/order.ts b/source/logic/order.ts
index 302a8eb..52ffb3d 100644
--- a/source/logic/order.ts
+++ b/source/logic/order.ts
@@ -519,10 +519,13 @@ namespace _heimdall.order
 			throw new Error("circular dependency detected")
 		}
 		else {
-			const order_raw = lib_plankton.json.decode(await lib_plankton.file.read(path));
+			const order_raw : {
+				includes ?: Array<string>;
+				checks ?: Array<any>;
+			} = lib_plankton.json.decode(await lib_plankton.file.read(path));
 			let includes : Array<string> = (
 				("includes" in order_raw)
-				? order_raw["includes"]
+				? order_raw.includes
 				: []
 			);
 			for (let index = 0; index < includes.length; index += 1) {
@@ -541,9 +544,9 @@ namespace _heimdall.order
 					}
 				)
 				if (! ("checks" in order_raw)) {
-					order_raw["checks"] = [];
+					order_raw.checks = [];
 				}
-				order_raw["checks"].extend(
+				order_raw.checks = order_raw.checks.concat(
 					sub_order.checks
 					.map(
 						check => Object.assign(
@@ -561,7 +564,7 @@ namespace _heimdall.order
 						sub_order.checks
 					)
 				);
-				order_raw["includes"] = [];
+				order_raw.includes = [];
 			}
 			return normalize_root(
 				check_kind_implementations,
diff --git a/tools/heimdall.prj.json b/tools/heimdall.prj.json
index 60e4eb3..be39629 100644
--- a/tools/heimdall.prj.json
+++ b/tools/heimdall.prj.json
@@ -26,6 +26,7 @@
 										"source/logic/notification_kinds/console.ts",
 										"source/logic/check_kinds/_abstract.ts",
 										"source/logic/check_kinds/http_request.ts",
+										"source/logic/check_kinds/file_state.ts",
 										"source/logic/state_repository.ts",
 										"source/logic/order.ts",
 										"source/logic/main.ts"
@@ -60,6 +61,7 @@
 				}
 			},
 			{
+				"active": false,
 				"name": "node_modules",
 				"type": "copy",
 				"parameters": {