Running Ruby 4 with Ruby::BOX inside Docker (Alpine)

Ruby 4 with Ruby::BOX

December 24, 2025

Ruby 4 introduces one of the most important runtime features in the history of the language: Ruby::BOX. It allows Ruby to execute multiple isolated class worlds inside the same process, finally making it possible to load conflicting libraries, plugins, and user code safely.

In this guide we will build a lightweight Alpine-based Docker image running Ruby 4.0.0-preview3 and demonstrate how Ruby::BOX enables true code isolation.

Dive deeper into this real-world Ruby case study.

Read the complete article:

👉 https://rubystacknews.com/2025/12/26/ruby-at-the-front-line-of-disaster-prevention/