diff --git a/lib/plankton/plankton.d.ts b/lib/plankton/plankton.d.ts
index 131483a..1407ed5 100644
--- a/lib/plankton/plankton.d.ts
+++ b/lib/plankton/plankton.d.ts
@@ -1,11 +1,11 @@
 /**
  * @author fenris
  */
-type int = number;
+declare type int = number;
 /**
  * @author fenris
  */
-type float = number;
+declare type float = number;
 declare class Buffer {
     constructor(x: string, modifier?: string);
     toString(modifier?: string): string;
@@ -19,7 +19,7 @@ declare namespace lib_plankton.base {
 /**
  * @author fenris
  */
-type type_pseudopointer<type_value> = {
+declare type type_pseudopointer<type_value> = {
     value: type_value;
 };
 /**
@@ -868,33 +868,11 @@ declare namespace lib_plankton.call {
         fallback?: (null | ((coproduct?: type_coproduct) => type_output));
     }): type_output;
     /**
-     * for rate_limit_check
-     *
-     * @author fenris
      */
-    type type_mana_snapshot = {
-        timestamp: float;
-        value: float;
+    function try_catch_wrap<type_value>(get_value: (() => type_value)): {
+        value: (null | type_value);
+        error: (null | any);
     };
-    /**
-     * rate limiting algorithm, based on the idea of mana (magic power) in video games:
-     * - an actor has a fixed mana capacity, i.e. the maximum amount of available power
-     * - an actor has a fixed rate of mana regeneration, i.e. how fast the power is filled up (linear growth)
-     * - an action has a defined mana heft, i.e. how much power is required and deducted in order to execute it
-     * - mana states are represented by snapshots, i.e. the amount of power at a certain point in time
-     *
-     * @author fenris
-     */
-    function rate_limit_check(setup: {
-        capacity: float;
-        regeneration_rate: float;
-        get_snapshot: (() => Promise<(null | type_mana_snapshot)>);
-        set_snapshot: ((snapshot: type_mana_snapshot) => Promise<void>);
-        update_snapshot: ((timestamp: float, value_increment: float) => Promise<void>);
-    }, heft: float): Promise<{
-        granted: boolean;
-        seconds: (null | float);
-    }>;
 }
 declare namespace lib_plankton.file {
     /**
@@ -1825,7 +1803,7 @@ declare namespace lib_plankton.storage.memory {
         clear(): Promise<void>;
         write(key: any, value: any): Promise<boolean>;
         delete(key: any): Promise<void>;
-        read(key: any): Promise<Awaited<type_item>>;
+        read(key: any): Promise<type_item>;
         search(term: any): Promise<{
             key: string;
             preview: string;
@@ -3014,7 +2992,7 @@ declare namespace lib_plankton.pit {
     /**
      * @todo test
      */
-    function to_datetime(pit: type_pit, options?: {
+    function to_datetime(pit: type_pit, { timezone_shift, }?: {
         timezone_shift?: int;
     }): type_datetime;
     /**
@@ -3064,6 +3042,48 @@ declare namespace lib_plankton.pit {
      * @todo write tests
      */
     function cest_switch_off(year: int): type_pit;
+    /**
+     */
+    function timezone_shift_ce(pit: type_pit): int;
+    /**
+     * [convenience]
+     */
+    function to_datetime_ce(pit: type_pit): type_datetime;
+    /**
+     */
+    function datetime_translate(datetime: type_datetime, timezone_shift: int): type_datetime;
+    /**
+     * [convenience]
+     */
+    function datetime_translate_ce(datetime: type_datetime): type_datetime;
+    /**
+     */
+    function timezone_shift_format(timezone_shift: int): string;
+    /**
+     */
+    function date_format(date: type_date): string;
+    /**
+     */
+    function time_format(time: type_time, { show_seconds, }?: {
+        show_seconds?: boolean;
+    }): string;
+    /**
+     * @todo show timezone
+     */
+    function datetime_format(datetime: (null | type_datetime), { timezone_indicator, show_timezone, adjust_to_ce, omit_date, }?: {
+        timezone_indicator?: string;
+        show_timezone?: boolean;
+        adjust_to_ce?: boolean;
+        omit_date?: boolean;
+    }): string;
+    /**
+     */
+    function timespan_format(from: type_datetime, to: (null | type_datetime), { timezone_indicator, show_timezone, adjust_to_ce, omit_date, }?: {
+        timezone_indicator?: string;
+        show_timezone?: boolean;
+        adjust_to_ce?: boolean;
+        omit_date?: boolean;
+    }): string;
 }
 declare namespace lib_plankton.www_form {
     /**
diff --git a/lib/plankton/plankton.js b/lib/plankton/plankton.js
index fe44d46..43c4b1e 100644
--- a/lib/plankton/plankton.js
+++ b/lib/plankton/plankton.js
@@ -2046,63 +2046,22 @@ var lib_plankton;
         }
         call.distinguish = distinguish;
         /**
-         * rate limiting algorithm, based on the idea of mana (magic power) in video games:
-         * - an actor has a fixed mana capacity, i.e. the maximum amount of available power
-         * - an actor has a fixed rate of mana regeneration, i.e. how fast the power is filled up (linear growth)
-         * - an action has a defined mana heft, i.e. how much power is required and deducted in order to execute it
-         * - mana states are represented by snapshots, i.e. the amount of power at a certain point in time
-         *
-         * @author fenris
          */
-        async function rate_limit_check(setup, heft) {
-            if (heft > setup.capacity) {
-                return Promise.resolve({
-                    "granted": false,
-                    "seconds": null,
-                });
+        function try_catch_wrap(get_value) {
+            try {
+                return {
+                    "value": get_value(),
+                    "error": null,
+                };
             }
-            else {
-                // get current value
-                const current_timestamp = (Date.now() / 1000);
-                const old_snapshot_raw = (await setup.get_snapshot());
-                const old_snapshot = (old_snapshot_raw
-                    ??
-                        { "timestamp": current_timestamp, "value": setup.capacity });
-                const seconds_passed = (current_timestamp - old_snapshot.timestamp);
-                const current_value = Math.min(setup.capacity, (old_snapshot.value
-                    +
-                        (setup.regeneration_rate
-                            *
-                                seconds_passed)));
-                // analyze
-                if (current_value < heft) {
-                    // too less
-                    const seconds_needed = ((setup.regeneration_rate <= 0)
-                        ? null
-                        : ((heft - old_snapshot.value) / setup.regeneration_rate));
-                    return Promise.resolve({
-                        "granted": false,
-                        "seconds": ((seconds_needed === null) ? null : (seconds_needed - seconds_passed)),
-                    });
-                }
-                else {
-                    // enough -> update snapshot
-                    const new_value = (current_value - heft);
-                    // set_snapshot
-                    if (old_snapshot_raw === null) {
-                        await setup.set_snapshot({ "timestamp": current_timestamp, "value": new_value });
-                    }
-                    else {
-                        await setup.update_snapshot(current_timestamp, (new_value - old_snapshot.value));
-                    }
-                    return Promise.resolve({
-                        "granted": true,
-                        "seconds": 0,
-                    });
-                }
+            catch (error) {
+                return {
+                    "value": null,
+                    "error": error,
+                };
             }
         }
-        call.rate_limit_check = rate_limit_check;
+        call.try_catch_wrap = try_catch_wrap;
     })(call = lib_plankton.call || (lib_plankton.call = {}));
 })(lib_plankton || (lib_plankton = {}));
 /*
@@ -2225,7 +2184,7 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
     function verb(n) { return function (v) { return step([n, v]); }; }
     function step(op) {
         if (f) throw new TypeError("Generator is already executing.");
-        while (g && (g = 0, op[0] && (_ = 0)), _) try {
+        while (_) try {
             if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
             if (y = 0, t) op = [op[0] & 2, t.value];
             switch (op[0]) {
@@ -3824,7 +3783,7 @@ var lib_plankton;
                         return {
                             "reports": [
                                 {
-                                    "incident": "no valid apaptions",
+                                    "incident": "no valid adaptions",
                                     "details": {
                                         "sub_adaptions": sub_adaptions,
                                     }
@@ -4634,11 +4593,16 @@ var lib_plankton;
                     if (options.legacy) {
                         const value = args[key];
                         const regexp_argument = new RegExp("\\${" + key + "}", "g");
-                        lib_plankton.log.debug("lib_plankton.string.coin", {
-                            "key": key,
-                            "regex": regexp_argument.toString(),
-                            "value": value,
-                        });
+                        /*
+                        lib_plankton.log.debug(
+                            "lib_plankton.string.coin",
+                            {
+                                "key": key,
+                                "regex": regexp_argument.toString(),
+                                "value": value,
+                            }
+                        );
+                         */
                         str = str.replace(regexp_argument, value);
                     }
                 }
@@ -4646,11 +4610,16 @@ var lib_plankton;
                 {
                     const value = args[key];
                     const regexp_argument = new RegExp(options.open + key + options.close, "g");
-                    lib_plankton.log.debug("lib_plankton.string.coin", {
-                        "key": key,
-                        "regex": regexp_argument.toString(),
-                        "value": value,
-                    });
+                    /*
+                    lib_plankton.log.debug(
+                        "lib_plankton.string.coin",
+                        {
+                            "key": key,
+                            "regex": regexp_argument.toString(),
+                            "value": value,
+                        }
+                    );
+                     */
                     str = str.replace(regexp_argument, value);
                 }
             });
@@ -6735,12 +6704,6 @@ var lib_plankton;
          * @author fenris
          */
         class class_relation {
-            /**
-             * @author fenris
-             */
-            check(value, reference) {
-                return this.predicate(value, reference);
-            }
             /**
              * @author fenris
              */
@@ -6750,6 +6713,12 @@ var lib_plankton;
                 this.name = name;
                 this.predicate = predicate;
             }
+            /**
+             * @author fenris
+             */
+            check(value, reference) {
+                return this.predicate(value, reference);
+            }
             /**
              * @author fenris
              */
@@ -8421,18 +8390,15 @@ var lib_plankton;
         /**
          * @todo test
          */
-        function to_datetime(pit, options = {}) {
-            options = Object.assign({
-                "timezone_shift": 0,
-            }, options);
+        function to_datetime(pit, { timezone_shift = 0, } = {}) {
             return lib_plankton.call.convey(pit, [
                 to_date_object,
                 (x) => x.getTime(),
-                (x) => (x + ((options.timezone_shift * (60 * 60)) * 1000)),
+                (x) => (x + ((timezone_shift * (60 * 60)) * 1000)),
                 (x) => new Date(x),
                 x => x.toISOString(),
                 x => ({
-                    "timezone_shift": options.timezone_shift,
+                    "timezone_shift": timezone_shift,
                     "date": {
                         "year": parseInt(x.slice(0, 4)),
                         "month": parseInt(x.slice(5, 7)),
@@ -8729,6 +8695,182 @@ var lib_plankton;
             ]);
         }
         pit_1.cest_switch_off = cest_switch_off;
+        /**
+         */
+        function timezone_shift_ce(pit) {
+            const year = to_datetime(pit).date.year;
+            return (is_between(pit, cest_switch_on(year), cest_switch_off(year))
+                ? +2
+                : +1);
+        }
+        pit_1.timezone_shift_ce = timezone_shift_ce;
+        /**
+         * [convenience]
+         */
+        function to_datetime_ce(pit) {
+            return to_datetime(pit, {
+                "timezone_shift": timezone_shift_ce(pit),
+            });
+        }
+        pit_1.to_datetime_ce = to_datetime_ce;
+        /**
+         */
+        function datetime_translate(datetime, timezone_shift) {
+            if (datetime.timezone_shift === timezone_shift) {
+                return datetime;
+            }
+            else {
+                const pit = from_datetime(datetime);
+                const pit_shifted = shift_hour(pit, (timezone_shift - datetime.timezone_shift));
+                const datetime_shifted = to_datetime(pit_shifted);
+                return {
+                    "timezone_shift": timezone_shift,
+                    "date": datetime_shifted.date,
+                    "time": ((datetime.time === null)
+                        ?
+                            null
+                        : datetime_shifted.time)
+                };
+            }
+        }
+        pit_1.datetime_translate = datetime_translate;
+        /**
+         * [convenience]
+         */
+        function datetime_translate_ce(datetime) {
+            return datetime_translate(datetime, timezone_shift_ce(from_datetime(datetime)));
+        }
+        pit_1.datetime_translate_ce = datetime_translate_ce;
+        /**
+         */
+        function timezone_shift_format(timezone_shift) {
+            return lib_plankton.string.coin("{{sign}}{{value}}", {
+                "sign": ((timezone_shift === 0)
+                    ?
+                        " "
+                    :
+                        ((timezone_shift > 0)
+                            ?
+                                "+"
+                            :
+                                "-")),
+                "value": Math.abs(timezone_shift).toFixed(0),
+            });
+        }
+        pit_1.timezone_shift_format = timezone_shift_format;
+        /**
+         */
+        function date_format(date) {
+            return lib_plankton.string.coin("{{year}}-{{month}}-{{day}}", {
+                "year": date.year.toFixed(0).padStart(4, "0"),
+                "month": date.month.toFixed(0).padStart(2, "0"),
+                "day": date.day.toFixed(0).padStart(2, "0"),
+            });
+        }
+        pit_1.date_format = date_format;
+        /**
+         */
+        function time_format(time, { show_seconds = false, } = {}) {
+            return lib_plankton.string.coin((show_seconds
+                ?
+                    "{{hour}}:{{minute}}:{{seconds}}"
+                :
+                    "{{hour}}:{{minute}}"), {
+                "hour": time.hour.toFixed(0).padStart(2, "0"),
+                "minute": time.minute.toFixed(0).padStart(2, "0"),
+                "second": time.second.toFixed(0).padStart(2, "0"),
+            });
+        }
+        pit_1.time_format = time_format;
+        /**
+         * @todo show timezone
+         */
+        function datetime_format(datetime, { timezone_indicator = "", show_timezone = false, adjust_to_ce = false, omit_date = false, } = {}) {
+            if (datetime === null) {
+                return "-";
+            }
+            else {
+                const datetime_adjusted = (adjust_to_ce
+                    ?
+                        to_datetime_ce(from_datetime(datetime))
+                    :
+                        datetime);
+                return lib_plankton.string.coin("{{macro_date_and_time}}{{macro_timezone}}", {
+                    "macro_date_and_time": ([
+                        // date
+                        (omit_date
+                            ?
+                                null
+                            :
+                                date_format(datetime_adjusted.date)),
+                        // time
+                        ((datetime_adjusted.time === null)
+                            ?
+                                null
+                            :
+                                time_format(datetime_adjusted.time)),
+                    ]
+                        .filter(x => (x !== null))
+                        .join(", ")),
+                    "macro_timezone": (show_timezone
+                        ?
+                            lib_plankton.string.coin(" [{{timezone_indicator}}{{timezone_value}}]", {
+                                "timezone_indicator": timezone_indicator,
+                                "timezone_value": timezone_shift_format(datetime_adjusted.timezone_shift),
+                            })
+                        :
+                            ""),
+                });
+            }
+        }
+        pit_1.datetime_format = datetime_format;
+        /**
+         */
+        function timespan_format(from, to, { timezone_indicator = "", show_timezone = false, adjust_to_ce = false, omit_date = false, } = {}) {
+            const from_adjusted = (adjust_to_ce
+                ?
+                    datetime_translate_ce(from)
+                :
+                    from);
+            const to_adjusted = ((to === null)
+                ?
+                    null
+                :
+                    (adjust_to_ce
+                        ?
+                            datetime_translate_ce(to)
+                        :
+                            to));
+            return lib_plankton.string.coin("{{from}}{{to_macro}}{{macro_timezone}}", {
+                "from": datetime_format(from_adjusted, {
+                    "show_timezone": false,
+                    "adjust_to_ce": false,
+                    "omit_date": omit_date,
+                }),
+                "to_macro": ((to_adjusted === null)
+                    ?
+                        ""
+                    :
+                        lib_plankton.string.coin(" - {{to}}", {
+                            "to": datetime_format(to_adjusted, {
+                                "omit_date": ((from_adjusted.date.year === to_adjusted.date.year)
+                                    &&
+                                        (from_adjusted.date.month === to_adjusted.date.month)
+                                    &&
+                                        (from_adjusted.date.day === to_adjusted.date.day))
+                            }),
+                        })),
+                "macro_timezone": (show_timezone
+                    ?
+                        lib_plankton.string.coin(" [{{timezone_indicator}}{{timezone_value}}]", {
+                            "timezone_indicator": timezone_indicator,
+                            "timezone_value": timezone_shift_format(from_adjusted.timezone_shift),
+                        })
+                    :
+                        ""),
+            });
+        }
+        pit_1.timespan_format = timespan_format;
     })(pit = lib_plankton.pit || (lib_plankton.pit = {}));
 })(lib_plankton || (lib_plankton = {}));
 /*