The Forge

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Overall Completion0 / 133 Solved (0%)

Challenges Solved

133

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core

Free

Implement debounce

15 min

core

Pro

Implement throttle

15 min

core

Pro

Implement memoize

15 min

core

Free

Implement curry

20 min

core

Pro

Implement a deep clone

20 min

core

Pro

Implement an event emitter

20 min

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The Forge

Practice Progress & Track Mastery

Track-by-Track Completion

Advanced JavaScript & ES6+

Polyfills & Built-ins

Data Manipulation

Coding-Round Classics

API & Network Concurrency

React Patterns

AI & Streaming

Start here

Implement debounce

Implement throttle

Implement memoize

Implement curry

Implement a deep clone

Implement an event emitter

Implement debounce

Implement curry

Implement throttle

Implement Promise.all from scratch

Implement a deep clone

Implement an event emitter

Implement memoize

Implement async retry with exponential backoff

Array

Implement myMap (Array.prototype.map)

Implement myFilter (Array.prototype.filter)

Implement myForEach (Array.prototype.forEach)

Implement myReduce (with and without an initial value)

Implement myFind (Array.prototype.find)

Implement mySome (Array.prototype.some)

Implement myEvery (Array.prototype.every)

Implement myFlat (Array.prototype.flat)

Implement myFlatMap (Array.prototype.flatMap)

Function

Implement myCall (Function.prototype.call)

Implement myApply (Function.prototype.apply)

Implement myBind (Function.prototype.bind)

Promise

Implement myRace (Promise.race)

Implement myAllSettled (Promise.allSettled)

Implement myAny (Promise.any)

Implement promisify(callbackFn)

Build a mini Promise from scratch (MyPromise)

Object

Implement myObjectAssign (Object.assign)

Implement myEntries (Object.entries)

Implement myFromEntries (Object.fromEntries)

Implement deepFreeze

Implement myInstanceof

Implement myNew (the new operator)

Implement getType (precise type detection)

Functional

Implement once(fn)

Implement partial(fn, ...presetArgs)

Implement negate(predicate)

Implement pipe and compose

Collection

Implement keyBy(arr, keyFn)

Implement countBy(arr, keyFn)

Implement chunk(arr, size)

Implement pick(obj, keys)

Implement omit(obj, keys)

Implement invert(obj)

Implement range(start, end, step)

Implement groupBy(arr, keyFn)

Implement partition(arr, predicate)

Implement uniqueBy(arr, keyFn)

Implement mapValues(obj, fn)

Implement zip(...arrays)

Implement unzip(arr)

Deep & Path

Implement get(obj, path, defaultValue)

Implement set(obj, path, value)

Implement mergeDeep(a, b)

Implement flattenDeep(arr)

Implement deepEqual(a, b)

Set & Sort

Implement intersectionBy, differenceBy, unionBy