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On-Device Debugging and JUnit 5

Jun 17th 2026, 15:00 by Shai Almog

This is the first follow-up to Friday's release post, and it covers the two changes from this release that affect how you iterate on a Codename One app rather than what the app itself does. On-device debugging that treats Java as Java on a real iPhone or a real Android device, and standard JUnit 5 against the JavaSE simulator. The first is the one we have been wanting for a long time, and is the one that takes the most explaining, so most of the post is about it.

On-Device Debugging That Treats Java as Java

Codename One has always supported on-device debugging in the strict technical sense. You could attach Xcode to a .ipa, you could attach Android Studio to a running APK, you could read the native call stack, you could step through Objective-C or the C that ParparVM emits. What you could not do was set a breakpoint in MyForm.java, hit it on a real iPhone, and inspect a Java field on a Java object as a Java object. You also could not debug an iOS app without a Mac in the loop somewhere, because the only debugger that understood the binary was Xcode. The translation step between the Java you wrote and the C that ParparVM produces left no way back across the gap on the device.

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Grok AI API Tutorial: Chat, Image, Video, Tool Calling, and Web Search

Jun 17th 2026, 14:31 by Hilman Ramadhan

The xAI Grok API provides access to powerful frontier models, including the Grok 4 series, supporting chat completions (text + vision), image generation, tool calling (function calling and built-in tools like web search), and more advanced features.

Quick Intro

Sign up at https://x.ai/api.
Generate an API key from the console.
Install pip install xai-sdk.
Set env var: export XAI_API_KEY="your_key_here".
Models list: https://docs.x.ai/developers/models.

I'll share some samples in Python.

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Optimizing Arm-Based Build Servers With AmpereOne CPUs

Jun 17th 2026, 14:28 by Dave Neary, John Oneill

What Makes a Good Build Server?

In modern cloud-native application development, Continuous Integration, with automated building and testing of software on every commit, has become a standard best practice. This typically involves maintaining a farm of build nodes, which can be physical devices, virtual machines, or containers, that can be provisioned on demand and retired once build tasks are completed.

This guide aims to help you configure the ultimate build server for Ampere's Arm-based architecture. We will explore various configuration options (or “knobs and switches”) to optimize a Linux build server’s performance, detailing the performance improvement with each adjustment.

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The Rise of Microservices Architecture in Scalable Applications

Jun 17th 2026, 14:00 by Mitchell Jhonson

In recent years, building modern applications has changed from what has been seen historically. Usually, in the past, systems were developed with a single, large block of code (referred to as a monolithic design) and would operate fairly well for smaller applications, but with time, as they got larger and more complex, the method of writing software became more of a hindrance to the applications as they required more users and increased speed.

Now, companies need their applications to be able to grow quickly, adapt to changes quickly, and be able to support millions of users without any impact on performance, and that is where microservice architecture is so relevant. Microservice architecture has become the way to design scalable applications because applications can be broken into smaller, individual services that can work independently from each other.

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WebSocket Debugging Without a Proxy — A Browser-First Workflow

Jun 17th 2026, 13:00 by Dan Pan

WebSocket debugging is one of those things that sounds simple until you actually have to do it. The connection looks fine in DevTools, but messages are malformed, timing is off, or the server is behaving unexpectedly — and you have no easy way to inspect what's happening at the frame level without setting up a proxy or installing something heavy.

Here's a practical workflow that requires nothing beyond a browser, illustrated with a real debugging scenario.

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