Jake Wharton

Let's render a simple page with Ktor server and kotlinx.html: get("/users.html") { call.respondHtml { myLayout(title = "Users") { userList( users = db.users.value, ) } } } A reusable myLayout provides scaffolding, userList…

Two months ago I gave my first ever live programming talk at KotlinConf.

I'm happy to announce that Retrofit, OkHttp, and Okio are moving to a new GitHub organization, and along with SQL Delight are all joining the Commonhaus Foundation.

Eight years ago we launched a library of Kotlin extensions for the Android platform, Android KTX.

Many people rely on the Compose bill of materials (BOM) artifact to provide the complete set of Compose dependency versions.

Did you know the versioning of AndroidX libraries and their stability guarantees are different from most libraries?

I used to use Bit.ly to put links into my presentations.

It doesn't take long for a project to spawn multiple jobs in their GitHub Actions.

JNI allows managed code inside the JVM or ART to call into native code.

When Espresso was made public a decade ago, one of its banner features was the "idling resource" concept.

You want to be using the latest JDK for development.

There was a time when I used Maven heavily, but today all the libraries I work on build with Gradle.

The last post featured some Kotlin code inadvertently targeting a new Java API when the build JDK was bumped to 21.

Yesterday, our Android app crashed with a weird NoSuchMethodError. java.lang.NoSuchMethodError: No interface method removeFirst()Ljava/lang/Object; in class Ljava/util/List; or its super classes (declaration of 'java.util.List' appears in /apex/com.androi…

Given an array of integers ([1, 2, 3, 1, 3, 1]), find the elements which are duplicated.

Given a list of users, extract their names and join them into a comma-separated list.

This post was published externally on Cash App Code Blog.

This post was published externally on Cash App Code Blog.

This post was published externally on Cash App Code Blog.

jlink is a JDK tool to create bespoke, minimal JREs for your applications.

Three years ago I gave the talk "What's new in Java 19: The end of Kotlin?"

In the past, when a new version of Java was released, I would add that version to our open source project's CI builds.

The equation y=mx+b defines a line in slope-intercept form.

This post was published externally on Cash App Code Blog.

My primary work project for the better part of a year (named Redwood) is built on top of Compose1 and runs on every platform that Kotlin supports.

This post was published externally on Cash App Code Blog.

Having been burned by case-insensitive filesystem bugs one too many times, I long ago switched my development folder to a case-sensitive filesystem partition on my otherwise case-insensitive Mac.

Earlier this year I built a web-based garage door controller using Rust for the Raspberry Pi called Normally Closed.

This post was published externally on Cash App Code Blog.

One of my favorite non-features from building view binding is that it lacks integration with activities or fragments.

This post was published externally on Cash App Code Blog.

I really like Jetpack Compose.

I use Docker to run a lot of tools.

Command-line programs use color to convey additional information and to look pretty.

How many times does the name of a layout file appear in an Android APK?

We'll get to the shrinking, but first let's motivate the binary in question.

This post was published externally on Cash App Code Blog.

Last year I built a library called Picnic for rendering data tables in monospaced environments like your terminal.

Note: This post is part of a series on D8 and R8, Android's new dexer and optimizer, respectively.

I've been porting the AndroidX collection library to Kotlin multiplatform to experiment with binary compatibility, performance, tooling, and the different memory models.

I recently played a minor role in helping add Cast support to an Android app.

When writing multiplatform code, Kotlin's three compiler backends each have different memory models which must be considered.

Note: This post is part of a series on D8 and R8, Android's new dexer and optimizer, respectively.

I want to remove Google as a single point of failure in my life.

I want to remove Google as a single point of failure in my life.

In 2010 I built a home server with five 2TB drives.

Note: This post is part of a series on D8 and R8, Android's new dexer and optimizer, respectively.

Kotlin is justifiably lauded for its language features compared to today's Java.

Note: This post is part of a series on D8 and R8, Android's new dexer and optimizer, respectively.

Note: This post is part of a series on D8 and R8, Android's new dexer and optimizer, respectively.