diff --git a/lib/plankton/plankton.d.ts b/lib/plankton/plankton.d.ts
index e094935..d03ea69 100644
--- a/lib/plankton/plankton.d.ts
+++ b/lib/plankton/plankton.d.ts
@@ -1,11 +1,11 @@
 /**
  * @author fenris
  */
-declare type int = number;
+type int = number;
 /**
  * @author fenris
  */
-declare type float = number;
+type float = number;
 declare var process: any;
 declare var require: any;
 declare class Buffer {
@@ -22,7 +22,7 @@ declare namespace lib_plankton.base {
 /**
  * @author fenris
  */
-declare type type_pseudopointer<type_value> = {
+type type_pseudopointer<type_value> = {
     value: type_value;
 };
 /**
@@ -2315,7 +2315,7 @@ 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<type_item>;
+        read(key: any): Promise<Awaited<type_item>>;
         search(term: any): Promise<{
             key: string;
             preview: string;
@@ -3073,22 +3073,25 @@ declare namespace lib_plankton.session {
     };
     /**
      */
-    function begin(name: string, options?: {
+    function begin(name: string, { "lifetime": lifetime, "data": data, }?: {
         lifetime?: int;
         data?: any;
     }): Promise<string>;
     /**
      */
-    function get(key: string): Promise<type_session>;
+    function get(key: string, { "prolongation": prolongation, }?: {
+        prolongation?: (null | int);
+    }): Promise<type_session>;
     /**
      */
     function end(key: string): Promise<void>;
     /**
      */
-    function setup(options?: {
+    function setup({ "key_length": key_length, "key_max_attempts": key_max_attempts, "default_lifetime": default_lifetime, "default_prolongation": default_prolongation, "data_chest": data_chest, "clear": clear, }?: {
         key_length?: int;
         key_max_attempts?: int;
         default_lifetime?: int;
+        default_prolongation?: (null | int);
         data_chest?: lib_plankton.storage.type_chest<string, any, void, string, string>;
         clear?: boolean;
     }): Promise<void>;
diff --git a/lib/plankton/plankton.js b/lib/plankton/plankton.js
index 58e904a..d423569 100644
--- a/lib/plankton/plankton.js
+++ b/lib/plankton/plankton.js
@@ -1486,7 +1486,7 @@ 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 (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) 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]) {
@@ -6814,7 +6814,7 @@ 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 (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) 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]) {
@@ -10266,7 +10266,7 @@ 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 (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) 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]) {
@@ -10325,21 +10325,37 @@ var lib_plankton;
         }
         /**
          */
-        function begin(name, options) {
-            if (options === void 0) { options = {}; }
+        function session_encode(session) {
+            return {
+                "key": session.key,
+                "name": session.name,
+                "expiry": Math.floor(session.expiry),
+                "data": JSON.stringify(session.data)
+            };
+        }
+        /**
+         */
+        function session_decode(session_raw) {
+            return {
+                "key": session_raw.key,
+                "name": session_raw.name,
+                "expiry": Math.floor(session_raw.expiry),
+                "data": JSON.parse(session_raw.data)
+            };
+        }
+        /**
+         */
+        function begin(name, _a) {
+            var _b = _a === void 0 ? {} : _a, _c = _b["lifetime"], lifetime = _c === void 0 ? _conf.default_lifetime : _c, _d = _b["data"], data = _d === void 0 ? null : _d;
             return __awaiter(this, void 0, void 0, function () {
                 var key, attempts, session_old, error_1, session_2, session_raw;
-                return __generator(this, function (_a) {
-                    switch (_a.label) {
+                return __generator(this, function (_e) {
+                    switch (_e.label) {
                         case 0:
-                            options = Object.assign({
-                                "lifetime": _conf.default_lifetime,
-                                "data": null
-                            }, options);
                             check_conf();
                             key = null;
                             attempts = 0;
-                            _a.label = 1;
+                            _e.label = 1;
                         case 1:
                             if (!true) return [3 /*break*/, 6];
                             attempts += 1;
@@ -10349,15 +10365,15 @@ var lib_plankton;
                                 function (x) { return x.join(""); },
                             ]);
                             session_old = null;
-                            _a.label = 2;
+                            _e.label = 2;
                         case 2:
-                            _a.trys.push([2, 4, , 5]);
+                            _e.trys.push([2, 4, , 5]);
                             return [4 /*yield*/, _conf.data_chest.read(key)];
                         case 3:
-                            session_old = _a.sent();
+                            session_old = _e.sent();
                             return [3 /*break*/, 5];
                         case 4:
-                            error_1 = _a.sent();
+                            error_1 = _e.sent();
                             session_old = null;
                             return [3 /*break*/, 5];
                         case 5:
@@ -10383,26 +10399,45 @@ var lib_plankton;
                             session_2 = {
                                 "key": key,
                                 "name": name,
-                                "expiry": (lib_plankton.base.get_current_timestamp() + options.lifetime),
-                                "data": options.data
+                                "expiry": (lib_plankton.base.get_current_timestamp() + lifetime),
+                                "data": data
                             };
-                            session_raw = {
-                                "key": session_2.key,
-                                "name": session_2.name,
-                                "expiry": Math.floor(session_2.expiry),
-                                "data": JSON.stringify(session_2.data)
-                            };
-                            lib_plankton.call.timeout(function () {
-                                lib_plankton.log.info("session_dropping_due_to_being_expired", {
-                                    "key": key,
-                                    "name": name,
-                                    "lifetime": options.lifetime
-                                });
-                                end(key);
-                            }, options.lifetime);
+                            session_raw = session_encode(session_2);
+                            /*
+                            lib_plankton.call.timeout(
+                                () => {
+                                    lib_plankton.log.info(
+                                        "session.dropping_due_to_being_expired",
+                                        {
+                                            "key": key,
+                                            "name": name,
+                                            "lifetime": lifetime,
+                                        }
+                                    );
+                                    end(key);
+                                },
+                                lifetime
+                            );
+                             */
                             return [4 /*yield*/, _conf.data_chest.write(key, session_raw)];
                         case 8:
-                            _a.sent();
+                            /*
+                            lib_plankton.call.timeout(
+                                () => {
+                                    lib_plankton.log.info(
+                                        "session.dropping_due_to_being_expired",
+                                        {
+                                            "key": key,
+                                            "name": name,
+                                            "lifetime": lifetime,
+                                        }
+                                    );
+                                    end(key);
+                                },
+                                lifetime
+                            );
+                             */
+                            _e.sent();
                             return [2 /*return*/, Promise.resolve(key)];
                     }
                 });
@@ -10411,29 +10446,51 @@ var lib_plankton;
         session_1.begin = begin;
         /**
          */
-        function get(key) {
-            check_conf();
-            return (_conf.data_chest.read(key)
-                .then(function (session_raw) {
-                var session = {
-                    "key": session_raw["key"],
-                    "name": session_raw["name"],
-                    "expiry": session_raw["expiry"],
-                    "data": JSON.parse(session_raw["data"])
-                };
-                var now = lib_plankton.base.get_current_timestamp();
-                if (now > session.expiry) {
-                    lib_plankton.log.info("session_dropping_due_to_being_stale", {
-                        "key": session.key,
-                        "name": session.name
-                    });
-                    end(key);
-                    return Promise.reject();
-                }
-                else {
-                    return Promise.resolve(session);
-                }
-            }));
+        function get(key, _a) {
+            var _b = _a === void 0 ? {} : _a, _c = _b["prolongation"], prolongation = _c === void 0 ? _conf.default_prolongation : _c;
+            return __awaiter(this, void 0, void 0, function () {
+                var session_raw, session, now, expiry_old, expiry_new;
+                return __generator(this, function (_d) {
+                    switch (_d.label) {
+                        case 0:
+                            check_conf();
+                            return [4 /*yield*/, _conf.data_chest.read(key)];
+                        case 1:
+                            session_raw = _d.sent();
+                            session = session_decode(session_raw);
+                            now = lib_plankton.base.get_current_timestamp();
+                            if (!(now <= session.expiry)) return [3 /*break*/, 6];
+                            if (!(prolongation === null)) return [3 /*break*/, 2];
+                            return [3 /*break*/, 5];
+                        case 2:
+                            expiry_old = session.expiry;
+                            expiry_new = Math.floor(now + prolongation);
+                            if (!(expiry_new < session.expiry)) return [3 /*break*/, 3];
+                            return [3 /*break*/, 5];
+                        case 3:
+                            lib_plankton.log.info("session.prolongating", {
+                                "key": key,
+                                "now": now,
+                                "prolongation": prolongation,
+                                "expiry_old": expiry_old,
+                                "expiry_new": expiry_new
+                            });
+                            session.expiry = expiry_new;
+                            return [4 /*yield*/, _conf.data_chest.write(key, session_encode(session))];
+                        case 4:
+                            _d.sent();
+                            _d.label = 5;
+                        case 5: return [2 /*return*/, Promise.resolve(session)];
+                        case 6:
+                            lib_plankton.log.info("session.dropping_due_to_being_stale", {
+                                "key": session.key,
+                                "name": session.name
+                            });
+                            end(key);
+                            return [2 /*return*/, Promise.reject()];
+                    }
+                });
+            });
         }
         session_1.get = get;
         /**
@@ -10445,29 +10502,23 @@ var lib_plankton;
         session_1.end = end;
         /**
          */
-        function setup(options) {
-            if (options === void 0) { options = {}; }
+        function setup(_a) {
+            var _b = _a === void 0 ? {} : _a, _c = _b["key_length"], key_length = _c === void 0 ? 16 : _c, _d = _b["key_max_attempts"], key_max_attempts = _d === void 0 ? 3 : _d, _e = _b["default_lifetime"], default_lifetime = _e === void 0 ? 900 : _e, _f = _b["default_prolongation"], default_prolongation = _f === void 0 ? null : _f, _g = _b["data_chest"], data_chest = _g === void 0 ? lib_plankton.storage.memory.implementation_chest({}) : _g, _h = _b["clear"], clear = _h === void 0 ? false : _h;
             return __awaiter(this, void 0, void 0, function () {
-                return __generator(this, function (_a) {
-                    switch (_a.label) {
+                return __generator(this, function (_j) {
+                    switch (_j.label) {
                         case 0:
-                            options = Object.assign({
-                                "key_length": 16,
-                                "key_max_attempts": 3,
-                                "default_lifetime": 900,
-                                "data_chest": lib_plankton.storage.memory.implementation_chest({}),
-                                "clear": false
-                            }, options);
                             _conf = {
-                                "key_length": options.key_length,
-                                "key_max_attempts": options.key_max_attempts,
-                                "default_lifetime": options.default_lifetime,
-                                "data_chest": options.data_chest
+                                "key_length": key_length,
+                                "key_max_attempts": key_max_attempts,
+                                "default_lifetime": default_lifetime,
+                                "default_prolongation": default_prolongation,
+                                "data_chest": data_chest
                             };
-                            if (!options.clear) return [3 /*break*/, 2];
+                            if (!clear) return [3 /*break*/, 2];
                             return [4 /*yield*/, _conf.data_chest.clear()];
                         case 1:
-                            _a.sent();
+                            _j.sent();
                             return [3 /*break*/, 2];
                         case 2: return [2 /*return*/, Promise.resolve(undefined)];
                     }
@@ -15148,7 +15199,7 @@ 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 (_) try {
+        while (g && (g = 0, op[0] && (_ = 0)), _) 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]) {