Konstantin Pavlov

A deceptively simple rule transforms a chaotic development team: break the build, buy cookies. What starts as lighthearted motivation evolves into a psychological experiment in collective responsibility and technical excellence. Twelve developers, one trunk, zero tolerance for broken builds—watch as pair programming sessions intensify, commits shrink to surgical precision, and a team discovers that the path to engineering perfection is paved with chocolate chips and mutual accountability. Sometimes the most profound transformations begin with the smallest consequences.

This article shows how to implement automated testing for LLM applications using promptfoo with a real application server, addressing the challenge that traditional testing methods fail with non-deterministic AI responses. The guide demonstrates testing conversation memory, tool integration, content moderation, and performance using a financial chatbot built with Quarkus and LangChain4j.

Discover why starting with API contracts first—not code—leads to clearer, more maintainable microservices. Learn the differences between contract-first and code-first approaches, common pitfalls to avoid, and why even small teams building alpha products benefit from clearly defined interfaces from day one. Get practical workflow tips and see how this approach can dramatically reduce integration headaches as your system grows.

Integrating Large Language Models (LLMs) into production systems presents unique architectural, testing, and operational challenges. This article shares practical insights and solutions from real-world experience integrating LLMs into a customer interaction platform. It covers the evolution from a monolithic to a more modular AI Proxy architecture pattern, strategies for testing, deploying and monitoring LLMs, and the emerging Model Context Protocol (MCP) standard. Application developers and software architects will learn proven practices to build robust, reliable and responsible LLM-powered systems.

Discover Kotlin extensions for LangChain4j designed to transform the synchronous LangChain4j API into a modern, non-blocking experience with Kotlin Coroutines. Learn about key features including coroutine support for ChatLanguageModels, Kotlin Flow for streaming responses, external customizable prompt templates, and non-blocking document processing. Enhance your Kotlin programming skills and improve application efficiency by leveraging these powerful new tools.