Kotlin

Join the Kotlin Track
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

10 Mentors

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

1,993 Students

Join hundreds 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.

Join the Kotlin track

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 Lidonis Calhau

Lidonis Calhau https://github.com/lidonis

I have been a web developer for quite some time. I really like Kotlin because it's design the way a would write a new OO language. I hope we can learn it a little bit better on this track.
Avatar of Jacob Andersen

Jacob Andersen https://github.com/simpleauthority

I've been using Kotlin for smaller projects for about a year. I find its simplicity and expressive nature very refreshing. I'm ready to help you bring your Kotlin skills to the next level.
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 Peter Nikodem

Peter Nikodem https://github.com/nikodem-peter

Came for Java, stayed for Kotlin. You can't see it in the picture, but I have fully functional arms and legs.
Avatar of Uzi Landsmann

Uzi Landsmann https://github.com/uzilan

I have been a developer for about 15 years, working daily with Java. I love learning new languages and am trying to learn and adopt a functional programming style.
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!
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.

Pig Latin
medium
arrays
lists
strings
transforming
Rotational Cipher
medium
cryptography
integers
strings
Prime Factors
medium
arrays
conditionals
integers
lists
loops
math
Difference Of Squares
easy
integers
loops
math
Luhn
medium
algorithms
booleans
loops
strings
type conversion
Pascal's Triangle
medium
algorithms
arrays
exception handling
integers
matrices
math
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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