diff --git a/later/later-test.ts b/later/later-test.ts
new file mode 100644
index 000000000..2d336d1b3
--- /dev/null
+++ b/later/later-test.ts
@@ -0,0 +1,631 @@
+/// <reference path="./later.d.ts"/>
+
+
+module LaterTest_DefineSchedule {
+
+    // define a new schedule
+    var textSched = later.parse.text('at 10:15am every weekday');
+    var cronSched = later.parse.cron('0 0/5 14,18 * * ?');
+    var recurSched = later.parse.recur().last().dayOfMonth();
+    var manualSched = <Later.IScheduleData>{ schedules: [ <Later.IRecurrence>{ M: [ 3 ], D: [ 21 ] } ] };
+    
+    // this schedule will fire on the closest weekday to the 15th
+    // every month at 2:00 am except in March
+    var complexSched = later.parse.recur()
+        .on(15).dayOfMonth().onWeekday().on(2).hour()
+        .and()
+        .on(14).dayOfMonth().on(6).dayOfWeek().on(2).hour()
+        .and()
+        .on(16).dayOfMonth().on(2).dayOfWeek().on(2).hour()
+        .except()
+        .on(3).month();
+}
+
+module LaterTest_ConfigureTimezone {
+
+    // set later to use UTC (the default)
+    later.date.UTC();
+
+    // set later to use local time
+    later.date.localTime();
+}
+
+module LaterTest_TimePeriods {
+    export function second() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.second.name;
+        // 'second'
+
+        later.second.range;
+        // 1
+
+        later.second.val(d);
+        // 5
+
+        later.second.isValid(d, 10);
+        // false
+
+        later.second.extent();
+        // [0, 59]
+
+        later.second.start(d);
+        // 'Fri, 22 Mar 2013 10:02:05 GMT'
+
+        later.second.end(d);
+        // 'Fri, 22 Mar 2013 10:02:05 GMT'
+
+        later.second.next(d, 27);
+        // 'Fri, 22 Mar 2013 10:02:27 GMT'
+
+        later.second.prev(d, 27);
+        // 'Fri, 22 Mar 2013 10:01:27 GMT'
+    }
+
+    export function minute() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.minute.name;
+        // 'minute'
+
+        later.minute.range;
+        // 60
+
+        later.minute.val(d);
+        // 2
+
+        later.minute.isValid(d, 2);
+        // true
+
+        later.minute.extent();
+        // [0, 59]
+
+        later.minute.start(d);
+        // 'Fri, 22 Mar 2013 10:02:00 GMT'
+
+        later.minute.end(d);
+        // 'Fri, 22 Mar 2013 10:02:59 GMT'
+
+        later.minute.next(d, 27);
+        // 'Fri, 22 Mar 2013 10:27:00 GMT'
+
+        later.minute.prev(d, 27);
+        // 'Fri, 22 Mar 2013 09:27:59 GMT'
+    }
+
+    export function hour() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.hour.name;
+        // 'hour'
+
+        later.hour.range;
+        // 3600
+
+        later.hour.val(d);
+        // 10
+
+        later.hour.isValid(d, 2);
+        // false
+
+        later.hour.extent();
+        // [0, 23]
+
+        later.hour.start(d);
+        // 'Fri, 22 Mar 2013 10:00:00 GMT'
+
+        later.hour.end(d);
+        // 'Fri, 22 Mar 2013 10:59:59 GMT'
+
+        later.hour.next(d, 5);
+        // 'Sat, 23 Mar 2013 05:00:00 GMT'
+
+        later.hour.prev(d, 21);
+        // 'Thu, 21 Mar 2013 21:59:59 GMT'
+    }
+
+    export function time() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.time.name;
+        // 'time'
+
+        later.time.range;
+        // 1
+
+        later.time.val(d);
+        // 36125
+
+        later.time.isValid(d, 36125);
+        // true
+
+        later.time.extent();
+        // [0, 86399]
+
+        later.time.start(d);
+        // 'Fri, 22 Mar 2013 00:00:00 GMT'
+
+        later.time.end(d);
+        // 'Fri, 22 Mar 2013 23:59:59 GMT'
+
+        later.time.next(d, 60);
+        // 'Sat, 23 Mar 2013 00:01:00 GMT'
+
+        later.time.prev(d, 60);
+        // 'Fri, 22 Mar 2013 00:01:00 GMT'
+    }
+
+    export function day() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.day.name;
+        // 'day'
+
+        later.day.range;
+        // 86400
+
+        later.day.val(d);
+        // 22
+
+        later.day.isValid(d, 3);
+        // false
+
+        later.day.extent(d);
+        // [1, 31]
+
+        later.day.start(d);
+        // 'Fri, 22 Mar 2013 00:00:00 GMT'
+
+        later.day.end(d);
+        // 'Fri, 22 Mar 2013 23:59:59 GMT'
+
+        later.day.next(d, 11);
+        // 'Thu, 11 Apr 2013 00:00:00 GMT'
+
+        later.day.prev(d, 2);
+        // 'Sat, 02 Mar 2013 23:59:59 GMT'
+    }
+
+    export function day_of_week() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.dayOfWeek.name;
+        // 'day of week'
+
+        later.dayOfWeek.range;
+        // 86400
+
+        later.dayOfWeek.val(d);
+        // 6
+
+        later.dayOfWeek.isValid(d, 3);
+        // false
+
+        later.dayOfWeek.extent();
+        // [1, 7]
+
+        later.dayOfWeek.start(d);
+        // 'Fri, 22 Mar 2013 00:00:00 GMT'
+
+        later.dayOfWeek.end(d);
+        // 'Fri, 22 Mar 2013 23:59:59 GMT'
+
+        later.dayOfWeek.next(d, 1);
+        // 'Sun, 24 Mar 2013 00:00:00 GMT'
+
+        later.dayOfWeek.prev(d, 5);
+        // 'Thu, 21 Mar 2013 23:59:59 GMT'
+    }
+
+    export function day_of_week_count() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.dayOfWeekCount.name;
+        // 'day of week count'
+
+        later.dayOfWeekCount.range;
+        // 604800
+
+        later.dayOfWeekCount.val(d);
+        // 4
+
+        later.dayOfWeekCount.isValid(d, 4);
+        // true
+
+        later.dayOfWeekCount.extent(d);
+        // [1, 5]
+
+        later.dayOfWeekCount.start(d);
+        // 'Fri, 22 Mar 2013 00:00:00 GMT'
+
+        later.dayOfWeekCount.end(d);
+        // 'Thu, 28 Mar 2013 23:59:59 GMT'
+
+        // zero is special cased and means the last instance of
+        // a day of the week in the month, instead of meaning the
+        // first day of the week with the highest instance count
+        // which would have been Mar 29 with value 5.
+        later.dayOfWeekCount.next(d, 0);
+        // 'Mon, 25 Mar 2013 00:00:00 GMT'
+
+        later.dayOfWeekCount.prev(d, 2);
+        // 'Thu, 14 Mar 2013 23:59:59 GMT'
+    }
+
+    export function day_of_year() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.dayOfYear.name;
+        // 'day of year'
+
+        later.dayOfYear.range;
+        // 86400
+
+        later.dayOfYear.val(d);
+        // 81
+
+        later.dayOfYear.isValid(d, 4);
+        // false
+
+        later.dayOfYear.extent(d);
+        // [1, 365]
+
+        later.dayOfYear.start(d);
+        // 'Fri, 22 Mar 2013 00:00:00 GMT'
+
+        later.dayOfYear.end(d);
+        // 'Fri, 22 Mar 2013 23:59:59 GMT'
+
+        later.dayOfYear.next(d, 256);
+        // 'Fri, 13 Sep 2013 00:00:00 GMT'
+
+        later.dayOfYear.prev(d, 44);
+        // 'Wed, 13 Feb 2013 23:59:59 GMT'
+    }
+
+    export function week_of_month() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.weekOfMonth.name;
+        // 'week of month'
+
+        later.weekOfMonth.range;
+        // 604800
+
+        later.weekOfMonth.val(d);
+        // 4
+
+        later.weekOfMonth.isValid(d, 4);
+        // true
+
+        later.weekOfMonth.extent(d);
+        // [1, 6]
+
+        later.weekOfMonth.start(d);
+        // 'Sun, 17 Mar 2013 00:00:00 GMT'
+
+        later.weekOfMonth.end(d);
+        // 'Sat, 23 Mar 2013 23:59:59 GMT'
+
+        later.weekOfMonth.next(d, 1);
+        // 'Mon, 01 Apr 2013 00:00:00 GMT'
+
+        later.weekOfMonth.prev(d, 2);
+        // 'Sat, 09 Mar 2013 23:59:59 GMT'
+    }
+
+    export function week_of_year() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.weekOfYear.name;
+        // 'week of year'
+
+        later.weekOfYear.range;
+        // 604800
+
+        later.weekOfYear.val(d);
+        // 12
+
+        later.weekOfYear.isValid(d, 21);
+        // false
+
+        later.weekOfYear.extent(d);
+        // [1, 52]
+
+        later.weekOfYear.start(d);
+        // 'Mon, 18 Mar 2013 00:00:00 GMT'
+
+        later.weekOfYear.end(d);
+        // 'Sun, 24 Mar 2013 23:59:59 GMT'
+
+        later.weekOfYear.next(d, 47);
+        // 'Mon, 18 Nov 2013 00:00:00 GMT'
+
+        later.weekOfYear.prev(d, 52);
+        // 'Sun, 30 Dec 2012 23:59:59 GMT'
+    }
+
+    export function month() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.month.name;
+        // 'month'
+
+        later.month.range;
+        // 2629740
+
+        later.month.val(d);
+        // 3
+
+        later.month.isValid(d, 3);
+        // true
+
+        later.month.extent();
+        // [1, 12]
+
+        later.month.start(d);
+        // 'Fri, 01 Mar 2013 00:00:00 GMT'
+
+        later.month.end(d);
+        // 'Sun, 31 Mar 2013 23:59:59 GMT'
+
+        later.month.next(d, 11);
+        // 'Fri, 01 Nov 2013 00:00:00 GMT'
+
+        later.month.prev(d, 2);
+        // 'Thu, 28 Feb 2013 23:59:59 GMT'
+    }
+
+    export function year() {
+        var d = new Date('2013-03-22T10:02:05Z');
+
+        later.year.name;
+        // 'year'
+
+        later.year.range;
+        // 31556900
+
+        later.year.val(d);
+        // 2013
+
+        later.year.isValid(d, 2013);
+        // true
+
+        later.year.extent();
+        // [1970, 2099]
+
+        later.year.start(d);
+        // 'Tue, 01 Jan 2013 00:00:00 GMT'
+
+        later.year.end(d);
+        // 'Tue, 31 Dec 2013 23:59:59 GMT'
+
+        later.year.next(d, 2014);
+        // 'Wed, 01 Jan 2014 00:00:00 GMT'
+
+        later.year.prev(d, 2012);
+        // 'Mon, 31 Dec 2012 23:59:59 GMT'
+    }
+
+    export interface IPartOfDayLater extends Later.IStatic {
+        partOfDay: Later.ITimePeriod;
+    }
+
+    export function custom() {
+
+        var customLater = <IPartOfDayLater>later;
+        
+        customLater.partOfDay = {
+
+            name: 'part of day',
+
+            range: later.hour.range * 6,
+
+            val: function(d: Date): number {
+                return later.hour.val(d) < 12 
+                    ? 0 
+                    : later.hour.val(d) < 18 
+                        ? 1 
+                        : 2;
+            },
+
+            isValid: function(d: Date, val: any) {
+                return customLater.partOfDay.val(d) === val;
+            },
+
+            extent: function(date?: Date) { 
+                return [0, 2]; 
+            },
+
+            start: function(date: Date) {
+                var hour = customLater.partOfDay.val(date) === 0 
+                    ? 0 
+                    : customLater.partOfDay.val(date) === 1 
+                        ? 12 
+                        : 18;
+
+                return later.date.next(
+                    later.year.val(date),
+                    later.month.val(date),
+                    later.day.val(date),
+                    hour
+                );
+            },
+
+            end: function(date: Date) {
+                var hour = customLater.partOfDay.val(date) === 0 
+                    ? 11 
+                    : customLater.partOfDay.val(date) === 1 
+                        ? 5 
+                        : 23;
+
+                return later.date.prev(
+                    later.year.val(date),
+                    later.month.val(date),
+                    later.day.val(date),
+                    hour
+                );
+            },
+
+            next: function(date: Date, val: any) {
+                var hour = val === 0 
+                    ? 0 
+                    : val === 1 
+                        ? 12 
+                        : 18;
+
+                return later.date.next(
+                    later.year.val(date),
+                    later.month.val(date),
+                    // increment the day if we already passed the desired time period
+                    later.day.val(date) + (hour < later.hour.val(date) ? 1 : 0),
+                    hour
+                );
+            },
+
+            prev: function(date: Date, val: any) {
+                var hour = val === 0 
+                    ? 11 
+                    : val === 1 
+                        ? 5 
+                        : 23;
+
+                return later.date.prev(
+                    later.year.val(date),
+                    later.month.val(date),
+                    // decrement the day if we already passed the desired time period
+                    later.day.val(date) + (hour > later.hour.val(date) ? -1 : 0), 
+                    hour
+                );
+            }
+        };
+    }
+}
+
+module LaterTest_GenerateRecurences {
+    
+    export function on_method() {
+        // fires on the 2nd minute every hour
+        later.parse.recur().on(2).minute();
+
+        // fires every day at 8am and 8pm
+        later.parse.recur().on(8, 20).hour();
+
+        // fires every day at 8am
+        later.parse.recur().on('08:00:00').time();
+    }
+
+    export function first_method() {
+        // fires on the 0th minute of every hour
+        later.parse.recur().first().minute();
+    }
+
+    export function last_method() {
+        // fires on the last day of every month at 5am
+        later.parse.recur().on(5).hour().last().dayOfMonth();
+    }
+
+    export function onWeekend_method() {
+        // fires on the 5th minute of every hour during Sat and Sun
+        later.parse.recur().on(5).minute().onWeekend();
+    }
+
+    export function onWeekday_method() {
+        // fires on the 5th minute of every hour during Mon,Tues,Wed,Thur,Fri
+        later.parse.recur().on(5).minute().onWeekday();
+    }
+
+    export function every_method() {
+        // fires on the 0th, 10th, 20th, 30th, 40th, and 50th min of every hour
+        later.parse.recur().every(10).minute();
+
+        // fires on first second of Jan, Apr, July, Oct
+        later.parse.recur().every(3).month();
+    }
+
+    export function after_method() {
+        // fires on the 55th, 56th, 57th, 58th, and 59th minute
+        later.parse.recur().after(55).minute();
+
+        // fires at 12 noon and 6pm
+        later.parse.recur().every(6).hour().after('09:00').time();
+    }
+
+    export function before_method() {
+        // fires on the first second of January and February
+        later.parse.recur().before(3).month();
+
+        // fires at 6am every day
+        later.parse.recur().every(6).hour().before('09:00').time();
+
+        // fires between 9am and 6pm every day
+        later.parse.recur().after('09:00').time().before('18:00').time();
+        later.parse.recur().after(9).hour().before(18).hour();
+    }
+
+    export function startingOn_method() {
+        // fires on the 10th, 25th, 40th, and 55th minute of every hour
+        later.parse.recur().every(15).minute().startingOn(10);
+    }
+
+    export function between_method() {
+        // fires on the 10th, 25th, 40th minute of every hour
+        later.parse.recur().every(15).minute().between(10, 40);
+    }
+
+    export function and_method() {
+        // fires every 2 hours on the first day of every month
+        // and 8:00am and 8:00pm on the last day of every month
+        var sched = later.parse.recur()
+            .every(2).hour().first().dayOfMonth()
+            .and()
+            .on(8, 20).hour().last().dayOfMonth()
+    }
+
+    export function except_method() {
+        // fires every minute of every hour except on multiples of 2 and 3
+        var sched = later.parse.recur()
+            .every().minute()
+            .except()
+            .every(2).minute().between(2, 59)
+            .and()
+            .every(3).minute().between(3, 59);
+    }
+
+}
+
+module LaterTest_CalculateOccurences {
+
+    // Initialise next variable.
+    var next: Date[] = [];
+
+    // calculate the next 10 occurrences of a recur schedule
+    var recurSched = later.parse.recur().last().dayOfMonth();
+
+    next = later.schedule(recurSched).next(10);
+
+    // calculate the previous occurrence starting from March 21, 2013
+    var cronSched = later.parse.cron('0 0/5 14,18 * * ?');
+
+    next = later.schedule(cronSched).prev(1, new Date(2013, 2, 21));
+}
+
+module LaterTest_ExecuteCodeUsingSchedule {
+
+    // will fire every 5 minutes
+    var textSched = later.parse.text('every 5 min');
+
+    // execute logTime one time on the next occurrence of the text schedule
+    var timer = later.setTimeout(logTime, textSched);
+
+    // execute logTime for each successive occurrence of the text schedule
+    var timer2 = later.setInterval(logTime, textSched);
+
+    // function to execute
+    function logTime() {
+        console.log(new Date());
+    }
+
+    // clear the interval timer when you are done
+    timer2.clear();
+}
\ No newline at end of file
diff --git a/later/later.d.ts b/later/later.d.ts
new file mode 100644
index 000000000..780de6398
--- /dev/null
+++ b/later/later.d.ts
@@ -0,0 +1,673 @@
+// Type definitions for LaterJS
+// Project: http://bunkat.github.io/later/
+// Definitions by: Jason D Dryhurst-Smith <http://jasonds.co.uk/>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+declare module Later {
+
+    export interface IScheduleData {
+
+        /** 
+         * A list of recurrence information as a composite schedule.
+         */
+        schedules: IRecurrence[];
+
+        /** 
+         * A list of exceptions to the composite recurrence information.
+         */
+        exceptions: IRecurrence[];
+
+        /** 
+         * A code to identify any errors in the composite schedule and exceptions.
+         * The number tells you the position of the error within the schedule.
+         */
+        error: number;
+    }
+
+    export interface IRecurrence {
+
+        /** Time in seconds from midnight.
+         */
+        t?: number[];
+        /** Seconds in minute.
+         */
+        s?: number[];
+        /** Minutes in hour.
+         */
+        m?: number[];
+        /** Hour in day.
+         */
+        h?: number[];
+        /** Day of the month.
+         */
+        D?: number[];
+        /** Day in week.
+         */
+        dw?: number[];
+        /** Nth day of the week in month.
+         */
+        dc?: number[];
+        /** Day in year.
+         */
+        dy?: number[];
+        /** Week in month.
+         */
+        wm?: number[];
+        /** ISO week in year.
+         */
+        wy?: number[];
+        /** Month in year.
+         */
+        M?: number[];
+        /** Year.
+         */
+        Y?: number[];
+
+        /** After modifiers.
+         */
+        t_a?: number[];
+        /** After modifiers.
+         */
+        s_a?: number[];
+        /** After modifiers.
+         */
+        m_a?: number[];
+        /** After modifiers.
+         */
+        h_a?: number[];
+        /** After modifiers.
+         */
+        D_a?: number[];
+        /** After modifiers.
+         */
+        dw_a?: number[];
+        /** After modifiers.
+         */
+        dc_a?: number[];
+        /** After modifiers.
+         */
+        dy_a?: number[];
+        /** After modifiers.
+         */
+        wm_a?: number[];
+        /** After modifiers.
+         */
+        wy_a?: number[];
+        /** After modifiers.
+         */
+        M_a?: number[];
+        /** After modifiers.
+         */
+        Y_a?: number[];
+
+        /** Before modifiers.
+         */
+        t_b?: number[];
+        /** Before modifiers.
+         */
+        s_b?: number[];
+        /** Before modifiers.
+         */
+        m_b?: number[];
+        /** Before modifiers.
+         */
+        h_b?: number[];
+        /** Before modifiers.
+         */
+        D_b?: number[];
+        /** Before modifiers.
+         */
+        dw_b?: number[];
+        /** Before modifiers.
+         */
+        dc_b?: number[];
+        /** Before modifiers.
+         */
+        dy_b?: number[];
+        /** Before modifiers.
+         */
+        wm_b?: number[];
+        /** Before modifiers.
+         */
+        wy_b?: number[];
+        /** Before modifiers.
+         */
+        M_b?: number[];
+        /** Before modifiers.
+         */
+        Y_b?: number[];
+        
+        /*
+         * Custom Time Periods and Modifiers
+         * For acces to custom time periods created as extension to the later static type
+         * and modifiers created on the later modifier static type.
+         */
+        [ timeperiodAndModifierName: string ]: number[]; 
+    }
+    
+    export interface IParseStatic {
+
+        /** 
+         * Create a recurrence builder for building schedule data.
+         */
+        recur(): IRecurrenceBuilder;
+
+        /** 
+         * Create schedule data by parsing a cron string
+         *
+         * @param {string} [input] - A string value to parse.
+         */
+        cron(input?: string): IScheduleData;
+
+        /** 
+         * Create schedule data by paring a human readable string.
+         *
+         * @param {string} [input] - A string value to parse.
+         */
+        text(input?: string): IScheduleData;
+    }
+
+    export interface ITimer {
+
+        /** 
+         * Clear the timer and end execution.
+         */
+        clear(): void;
+    }
+
+    export interface ISchedule {
+
+        /**
+        * Finds the next valid instance or instances of the current schedule,
+        * optionally between a specified start and end date. Start date is
+        * Date.now() by default, end date is unspecified. Start date must be
+        * smaller than end date.
+        *
+        * @param {number} numberOfInst: The number of instances to return
+        * @param {Date} dateFrom: The earliest a valid instance can occur
+        * @param {Date} dateTo: The latest a valid instance can occur
+        */
+        next(numberOfInst: number, dateFrom?: Date, dateTo?: Date): Date[];
+
+        /**
+        * Finds the next valid range or ranges of the current schedule,
+        * optionally between a specified start and end date. Start date is
+        * Date.now() by default, end date is unspecified. Start date must be
+        * greater than end date.
+        *
+        * @param {number} numberOfInst: The number of ranges to return
+        * @param {Date} dateFrom: The earliest a valid range can occur
+        * @param {Date} dateTo: The latest a valid range can occur
+        */
+        nextRange(numberOfInst: number, dateFrom?: Date, dateTo?: Date): Date[];
+
+        /**
+        * Finds the previous valid instance or instances of the current schedule,
+        * optionally between a specified start and end date. Start date is
+        * Date.now() by default, end date is unspecified. Start date must be
+        * greater than end date.
+        *
+        * @param {number} numberOfInst: The number of instances to return
+        * @param {Date} dateFrom: The earliest a valid instance can occur
+        * @param {Date} dateTo: The latest a valid instance can occur
+        */
+        prev(numberOfInst: number, dateFrom?: Date, dateTo?: Date): Date[];
+
+        /**
+        * Finds the previous valid range or ranges of the current schedule,
+        * optionally between a specified start and end date. Start date is
+        * Date.now() by default, end date is unspecified. Start date must be
+        * greater than end date.
+        *
+        * @param {number} numberOfInst: The number of ranges to return
+        * @param {Date} dateFrom: The earliest a valid range can occur
+        * @param {Date} dateTo: The latest a valid range can occur
+        */
+        prevRange(numberOfInst: number, dateFrom?: Date, dateTo?: Date): Date[];
+    }
+
+    export interface IRecurrenceBuilder extends IScheduleData {
+
+        /** a time period
+         */
+        second(): IRecurrenceBuilder;
+        /** a time period
+         */
+        minute(): IRecurrenceBuilder;
+        /** a time period
+         */
+        hour(): IRecurrenceBuilder;
+        /** a time period
+         */
+        time(): IRecurrenceBuilder;
+        /** a time period
+         */
+        dayOfWeek(): IRecurrenceBuilder;
+        /** a time period
+         */
+        dayOfWeekCount(): IRecurrenceBuilder;
+        /** a time period
+         */
+        dayOfMonth(): IRecurrenceBuilder;
+        /** a time period
+         */
+        dayOfYear(): IRecurrenceBuilder;
+        /** a time period
+         */
+        weekOfMonth(): IRecurrenceBuilder;
+        /** a time period
+         */
+        weekOfYear(): IRecurrenceBuilder;
+        /** a time period
+         */
+        month(): IRecurrenceBuilder;
+        /** a time period
+         */
+        year(): IRecurrenceBuilder;
+        
+        /** a time period
+         */
+        fullDate(): IRecurrenceBuilder;
+
+        /** 
+         * Specifies one or more specific vals of a time period information provider. 
+         * When used to specify a time, a string indicating the 24-hour time may be used.
+         * 
+         * @param {number[]} values - A list of values.
+         */
+        on(...values: number[]): IRecurrenceBuilder;
+        /** 
+         * Specifies one or more specific vals of a time period information provider. 
+         * When used to specify a time, a string indicating the 24-hour time may be used.
+         * 
+         * @param {string} value - A string representing your value.
+         */
+        on(value: string): IRecurrenceBuilder;
+        /** 
+         * Specifies one or more specific vals of a time period information provider. 
+         * When used to specify a time, a string indicating the 24-hour time may be used.
+         * 
+         * @param {Date} date - A Date representing your value.
+         */
+        on(date: Date): IRecurrenceBuilder;
+
+        /** 
+         * Preceed a time period. 
+         *
+         * @param {number} [value] - A number representing your value.
+         */ 
+        every(value?: number): IRecurrenceBuilder;
+        /** 
+         * Preceed a time period. 
+         *
+         * @param {string} [value] - A string representing your value.
+         */ 
+        every(value?: string): IRecurrenceBuilder;
+
+        /** 
+         * Preceed a time period. 
+         *
+         * @param {number} start - A number representing your start value.
+         * @param {number} end - A number representing your end value.
+         */
+        between(start: number, end: number): IRecurrenceBuilder;
+        /** 
+         * Preceed a time period. 
+         *
+         * @param {string} start - A string representing your start value.
+         * @param {string} end - A string representing your end value.
+         */
+        between(start: string, end: string): IRecurrenceBuilder;
+
+        /** 
+         * After a time period. 
+         *
+         * @param {number} value - A number representing your value.
+         */ 
+        after(value: number): IRecurrenceBuilder;
+        /** 
+         * After a time period. 
+         *
+         * @param {string} value - A string representing your value.
+         */ 
+        after(value: string): IRecurrenceBuilder;
+        
+        /** 
+         * After a time period. 
+         *
+         * @param {number} value - A number representing your value.
+         */ 
+        before(value: number): IRecurrenceBuilder;
+        /** 
+         * After a time period. 
+         *
+         * @param {string} value - A string representing your value.
+         */ 
+        before(value: string): IRecurrenceBuilder;
+        
+        /** 
+         * After a time period. 
+         *
+         * @param {number} value - A number representing your value.
+         */ 
+        startingOn(value: number): IRecurrenceBuilder;
+        /** 
+         * After a time period. 
+         *
+         * @param {string} value - A string representing your value.
+         */  
+        startingOn(value: string): IRecurrenceBuilder;
+
+        /** 
+         * Equivalent to .on(min)
+         */
+        first(): IRecurrenceBuilder;
+
+        /** 
+         * Equivalent to .on(max)
+         */
+        last(): IRecurrenceBuilder;
+
+        /** 
+         * Equivalent to .on(1,7).dayOfWeek()
+         */
+        onWeekend(): IRecurrenceBuilder;
+
+        /** 
+         * Equivalent to .on(2,3,4,5,6).dayOfWeek()
+         */
+        onWeekday(): IRecurrenceBuilder;
+
+        /** 
+         * Add a new schedule value to schedules, composite schedule.
+         */
+        and(): IRecurrenceBuilder;
+
+        /** 
+         * Add exceptions.
+         */
+        except(): IRecurrenceBuilder;
+
+        /** 
+         * Custom Timeperiod Recurrences.
+         * Using a key as defined by the custom period in any extension to Later.IStatic.
+         */
+        customPeriod(key: string): IRecurrenceBuilder;
+
+        /** 
+         * Customise Recurrences.
+         * Using a key as defined by the custom modifier in any extension to Later.IModifierStatic.
+         */
+        customModifier(key: string, values: number): IRecurrenceBuilder;
+    }
+
+    export interface IDateProvider {
+
+        /** 
+         * Set later to use UTC time. 
+         */
+        UTC(): void;
+
+        /** 
+         * Set later to use local time.
+         */
+        localTime(): void;
+
+        /**
+         * Builds and returns a new Date using the specified values.  Date
+         * returned is either using Local time or UTC based on isLocal.
+         *
+         * @param {number} [Y]: Four digit year
+         * @param {number} [M]: Month between 1 and 12, defaults to 1
+         * @param {number} [D]: Date between 1 and 31, defaults to 1
+         * @param {number} [h]: Hour between 0 and 23, defaults to 0
+         * @param {number} [m]: Minute between 0 and 59, defaults to 0
+         * @param {number} [s]: Second between 0 and 59, defaults to 0
+         */
+        next(Y?: number, M?: number, D?: number, h?: number, m?: number, s?: number): Date;
+
+        /**
+         * Builds and returns a new Date using the specified values.  Date
+         * returned is either using Local time or UTC based on isLocal.
+         *
+         * @param {number} [Y]: Four digit year
+         * @param {number} [M]: Month between 0 and 11, defaults to 11
+         * @param {number} [D]: Date between 1 and 31, defaults to last day of month
+         * @param {number} [h]: Hour between 0 and 23, defaults to 23
+         * @param {number} [m]: Minute between 0 and 59, defaults to 59
+         * @param {number} [s]: Second between 0 and 59, defaults to 59
+         */
+        prev(Y?: number, M?: number, D?: number, h?: number, m?: number, s?: number): Date;
+
+        /**
+         * Determines if a value will cause a particular constraint to rollover to the
+         * next largest time period. Used primarily when a constraint has a
+         * variable extent.
+         *
+         * @param {Date} d: Date
+         * @param {number} val: Value
+         * @param {IModifier} constraint: A modifier
+         * @param {ITimePeriod} period: A time period
+         */
+        nextRollover(d: Date, val: number, constraint: IModifier, period: ITimePeriod): Date;
+
+        /**
+         * Determines if a value will cause a particular constraint to rollover to the
+         * previous largest time period. Used primarily when a constraint has a
+         * variable extent.
+         *
+         * @param {Date} d: Date
+         * @param {number} val: Value
+         * @param {IModifier} constraint: A modifier
+         * @param {ITimePeriod} period: A time period
+         */
+        prevRollover(d: Date, val: number, constraint: IModifier, period: ITimePeriod): Date;
+    }
+    
+    export interface ITimePeriod {
+
+        /** 
+         * The name of the time period information provider.
+         */
+        name: string;
+
+        /** 
+         * The rough number of seconds that are covered when moving from one instance of this time period to the next instance.
+         */
+        range: number;
+
+        /** 
+         * The value of this time period for the date specified.
+         *
+         * @param {Date} date - The given date.
+         */
+        val(date: Date): number;
+
+        /** 
+         * True if the specified value is valid for the specified date, false otherwise.
+         *
+         * @param {Date} date - The given date.
+         * @param {any} value - The value to test for the date.
+         */
+        isValid(date: Date, value: any): boolean;
+
+        /** 
+         * The minimum and maximum valid values for the time period for the specified date.
+         * If the minimum value is not 0, 0 can be specified in schedules to indicate the maximum value.
+         * This makes working with non - constant extents(like days in a month) easier.
+         *
+         * @param {Date} [date] - The given date.
+         */
+        extent(date?: Date): number[];
+
+        /** 
+         * The first second in which the value is the same as the value of the specified date.
+         *  For example, the start of an hour would be the hour with 0 minutes and 0 seconds.
+         *
+         * @param {Date} date - The given date.
+         */
+        start(date: Date): Date;
+
+        /** 
+         * The last second in which the value is the same as the value of the specified date.
+         * For example, the end of an hour would be the hour with 59 minutes and 59 seconds.
+         *
+         * @param {Date} date - The given date.
+         */
+        end(date: Date): Date;
+
+        /** 
+         * Returns the next date where the value is the value specified.
+         * Sets the value to 1 if value specified is greater than the max allowed value.
+         *
+         * @param {Date} date - The given date.
+         * @param {any} value - The value to test for the date.
+         */
+        next(date: Date, value: any): Date;
+
+        /** 
+         * Returns the previous date where the value is the value specified.
+         * Sets the value to the max allowed value if the value specified is greater than the max allowed value. 
+         *
+         * @param {Date} date - The given date.
+         * @param {any} value - The value to test for the date.
+         */
+        prev(date: Date, value: any): Date;
+    }
+
+    export interface IModifier extends ITimePeriod {
+        /**
+         * Creates a new modified constraint.
+         *
+         * @param {ITimePeriod} constraint: The constraint to be modified
+         * @param {number} value: The starting value of the after constraint
+         */
+        (constraint: ITimePeriod, value: number): ITimePeriod;
+    }
+
+    export interface IModifierStatic {
+        
+        /**
+         * After Modifier
+         */
+        after: IModifier;
+
+        /**
+         * Before Modifier
+         */
+        before: IModifier;
+    }
+
+    export interface IStatic {
+        
+        /** 
+         * Schedule
+         * Generates instances from schedule data.
+         */
+        schedule(input: any): ISchedule;
+
+        /** 
+         * Parse 
+         * For generating schedule data.
+         */
+        parse: IParseStatic;
+
+        /** Date Provider
+         */
+        date: IDateProvider;
+
+        /** 
+         * Set timeout on window using given recurrence next.
+         *  
+         * @param {function} callback - A callback called after first instance of recurrence pattern.
+         * @param {Later.IReccurence} - A recurrence instance.
+         */
+        setTimeout(callback: () => void, time: IScheduleData): ITimer;
+        /** 
+         * Set interval on window using given recurrence
+         *  
+         * @param {function} callback - A callback called after each instance of recurrence pattern.
+         * @param {Later.IReccurence} - A recurrence instance.
+         */
+        setInterval(callback: () => void, time: IScheduleData): ITimer;
+
+        /** 
+         * time period information provider.
+         */
+        time: ITimePeriod;
+        /** 
+         * Second time period information provider.
+         */
+        second: ITimePeriod;
+        /** 
+         * Minute time period information provider.
+         */
+        minute: ITimePeriod;
+        /** 
+         * Hour time period information provider.
+         */
+        hour: ITimePeriod;
+        /** 
+         * Day time period information provider.
+         */
+        day: ITimePeriod;
+        /** 
+         * Day of week time period information provider.
+         */
+        dayOfWeek: ITimePeriod;
+        /** 
+         * Day of week in month time period information provider.
+         */
+        dayOfWeekCount: ITimePeriod;
+        /** 
+         * Day in year time period information provider.
+         */
+        dayOfYear: ITimePeriod;
+        /**
+         * Week of mobth time period information provider.
+         */
+        weekOfMonth: ITimePeriod;
+        /**
+         * Week of yearfrom ISO 8601 time period information provider.
+         */
+        weekOfYear: ITimePeriod;
+        /**
+         * Month time period information provider.
+         */
+        month: ITimePeriod;
+        /**
+         * Year time period information provider.
+         */
+        year: ITimePeriod;
+        
+        /**
+         * Later Modifiers:
+         * 
+         * This type can be easily extended to include any custom IModifiers that you desire.
+         * These can then be used to create schedules of your own custom type.
+         * 
+         * interface IGandalfsLaterModifier extends Later.IModifierStatic {
+         *     duringTheThirdAge: IModifier
+         * }
+         * 
+         * Be sure to use this interface when dealing with Later.modifier
+         */
+        modifier: IModifierStatic
+    }
+}
+
+/** 
+ * Later Module:
+ * 
+ * Easily define complex schedules then quickly calculate future or previous schedule occurrences.
+ * 
+ * This type can be easily extended to include any custom ITimePeriods that you desire.
+ * These can then be used to create schedules of your own custom type.
+ * 
+ * interface IGandalfsLater extends Later.IStatic {
+ *     agesOfMiddleEarth: ITimePeriod
+ * }
+ * 
+ * Be sure to use this interface when dealing with Later. 
+ */
+declare var later: Later.IStatic;
\ No newline at end of file