Optional Is a Law-breaking Monad but a Good Type

In most programming languages empty-or-not-empty types are well-behaved monads. (Yes, I used the M-word — don’t worry, no math.) This means their mechanics fulfill a couple of definitions and follow a number of laws that guarantee safe…

Uncheck Your Exceptions

Checked exceptions were an experiment — it’s time to move on

Learn to Kata and Kata to Learn

Every Java developer needs to continuously learn new skills as the Java ecosystem constantly evolves. The Java programming language now…

Debugging Java Microservices Running in Kubernetes Using Telepresence and IntelliJ

Read in the data in a Pandas DataFrame like an expert

Pandas DataFrame is widely popular in a typical…

The Case Against Fat JARs

In modern Java web development, the thought of packaging and running applications in anything other than a fat JAR is almost becoming heretical. However, there can be distinct disadvantages to building and deploying these artifacts. One obvious issue is the typically large size of…

Program with GUTs

Having GUTs means having good unit tests

Let’s Make a Contract: The Art of Designing a Java API

An API is what developers use to achieve some task. More precisely it establishes a contract between them and the designers of the software exposing its services through that API. In this sense we’re all API designers: Our software…

Name the Date

What we can learn from the sad tale of java.util.Date

The Rebirth of Java

Java has been declared dead more than any other programming language, it seems. As…