Kotlin

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Kotlin is a pragmatic programming language for JVM and Android that combines OO and functional features and is focused on interoperability, safety, clarity and tooling support.
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Track mentors

14 Mentors

Our mentors are friendly, experienced Kotlin developers who will help teach you new techniques and tricks.
Track students

2,521 Students

Join thousands of students who have enjoyed learning and improving their skills by taking this track.
Track exercises

63 Exercises

Hundreds of hours have gone into making these exercises fun, useful, and challenging to help you enjoy learning.

About Kotlin

fun getGreeting(): String {
    return "Hello, World!"
}

Kotlin was designed and developed by JetBrains, the company behind IntelliJ. It is a language that runs on the JVM which can target versions 6+ (including the Android platform). JetBrains wanted to use a statically typed language which can remove Java boilerplate code, provide modern functional paradigms, and had seamless two-way Java interoperability with their existing codebase. The JVM already had alternate languages like Groovy and Scala but neither fit the bill with their desired criteria, so they built Kotlin.

Kotlin syntax is similar to Scala and Swift but pulls in the best-of-breed features from other languages such as C# and Groovy. Kotlin took a pragmatic approach at features included in the language by only providing functionality that has been proven to be useful for developers. With this decision they implemented a subset of features of Scala with the intent that it will provide more maintainable code with an easier learning curve for developers looking for a "better Java".

JetBrains has a dedicated team of developers working on Kotlin with the codebase available on Github.

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Exercism is a great website

Exercism is a great website where I was able to have some very interesting challenges.

Relaxed. Encouraging. Supportive.

Meet the Kotlin Track mentors

Once you join the Kotlin language track, you will receive support and feedback from our team of mentors. Here are the bios of a few of the mentors of this track.

Avatar of Mike Gehard

Mike Gehard My musings on software.

I love writing Kotlin because it has some of the power of Scala without all of the type system complexity. It is a breath of fresh air in the Java ecosystem for those of us that like the JVM but don't like Java.
Avatar of Robin Roschlau

Robin Roschlau Twitter

I've been slightly addicted to Kotlin ever since I first used it, coming from Java a few years ago, so much so that I started a Kotlin User Group in my area and am regularly holding talks about it.
Avatar of Derk-Jan Karrenbeld

Derk-Jan Karrenbeld https://github.com/SleeplessByte

After being stuck with Java for 8 years, Kotlin was the fresh breath of joy I needed.
Avatar of Gurpreet Singh

Gurpreet Singh Website

I am an Android Developer based out of New Delhi, and have been working with Kotlin for over a year. I'm particularly interested in Functional & Reactive programming paradigm and like to share my knowledge and learn from others.
Avatar of Will Madison

Will Madison https://github.com/willmadison

Passionate developer. Live long learner. Father. Geek. Frat Boy :). I've written Kotlin professionaly and it is truly a lovely and pragmatic language!
Avatar of Sinuhe Jaime

Sinuhe Jaime https://github.com/sierisimo

I'm a geek doing a lot of things, including Kotlin. I've using the language for 3 years now but still learning everyday
Fun. Challenging. Interesting

Community-sourced Kotlin exercises

These are a few of the 63 exercises on the Kotlin track. You can see all the exercises here.

Beer Song
medium
conditionals
loops
strings
text formatting
variables
Hello World
easy
strings
Sum Of Multiples
medium
arrays
conditionals
integers
loops
math
ETL
medium
lists
maps
transforming
Change
hard
algorithms
exception handling
integers
lists
Saddle Points
medium
arrays
conditionals
exception handling
integers
loops
Passionate. Knowledgeable. Creative.

Meet the Kotlin Track maintainers

The Kotlin Maintainers are the brains behind the Kotlin Track. They spend their spare time creating interesting and challenging exercises that we can all learn from. We are incredibly grateful for their hard work. Here are the bios of a few of the maintainers of this track.

Avatar of Sam Warner

Sam Warner

I am a software developer and consultant working for Black Pepper Software, a software company based in Leamington Spa, England. I'm a recent Computer Science graduate from the University of Warwick, and love all things to do with computers!

Get started with the Kotlin track. As with everything on Exercism, it's 100% free!

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