Kotlin: IDE, Linters, and Formatters for Pros

Tools That Will Turn You Into a Kotlin Ninja

Have you ever spent an hour searching for an extra comma in your code? Or received a pull request with the comment "fix formatting"? If so — welcome to the club. If not — you're either a genius or you don't write in Kotlin. Just kidding. But there's a grain of truth in every joke: even the coolest code can look sloppy if you don't set up your tooling.

Today we'll talk about how to make your work with Kotlin not just productive, but comfortable. We'll break down IDEs, linters, and formatters — those "hidden gems" that distinguish a professional from an amateur. And yes, all of this will be with real examples, not abstract "well, something gets highlighted there".

1. IDE: Your Command Center

Let's start with the main thing — the development environment. If you write in Kotlin, you essentially have two paths: IntelliJ IDEA and Android Studio. Everything else is a compromise.

IntelliJ IDEA — The King of Kotlin

Yes, this is the obvious choice. But let's break down why exactly. IntelliJ IDEA is created by the same team as Kotlin itself (JetBrains). This means language support here isn't just "good", it's native.

What you get "out of the box":

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• Autocompletion that anticipates your thoughts. Write val list = listOf(1,2,3) and IDEA will suggest which methods you can call next.
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• Refactoring — renaming a variable, extracting a function, replacing if with when — all done in two clicks.
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• Navigation — Ctrl+Click on any symbol instantly takes you to its declaration.
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• Code Inspections — yellow and red light bulbs that highlight potential issues.
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Example of navigation in action:

// Let's say you have this code:\nfun processUsers(users: List<User>) {\n    users.forEach { user ->\n        println(user.name)\n    }\n}\n\n// Press Ctrl+B on "User" — and you'll immediately see data class User(...)

Tip: enable the Kotlin Fill Class plugin — it automatically generates stubs for classes you haven't created yet. Saves 10 minutes a day.

Android Studio — For Mobile Knights

If you write for Android, Android Studio is the same IntelliJ, but with additional goodies: emulator, profiler, layout editor. Kotlin is also natively supported here.

The main difference: Android Studio is slightly heavier, but gives access to the Android SDK and specific tools like Layout Inspector. For backend, it's better to use pure IntelliJ IDEA — it's lighter and faster.

2. Linters: Your Conscience in Code

A linter is a program that checks code for style, errors, and "bad practices". Imagine having a personal reviewer who never sleeps or eats, but only looks at your code and says: "And here it's better to use a sealed class instead of an enum".

KtLint — Fast and Strict

KtLint is the de facto standard for Kotlin. It checks formatting, indentation, spaces, import order. Everything that can be automated — it automates.

How to install? The easiest way is via Gradle:

plugins {\n    id("org.jlleitschuh.gradle.ktlint") version "12.0.3"\n}\n\n// Then in the terminal:\n./gradlew ktlintCheck   // check\n./gradlew ktlintFormat  // fix

Example: KtLint won't let this code pass:

fun hello(name:String){  // ❌ Error: no space before colon\n    println("Hello $name")\n}\n\n// Correct:\nfun hello(name: String) {  // ✅ Space is present\n    println("Hello $name")\n}

KtLint doesn't just complain — it can fix these errors itself. Run ktlintFormat and the code will become perfect.

detekt — A Detective for Code

If KtLint is the police officer, who