The article details a puzzling NoMethodError in a Ruby application using the FFI library. It uncovers a critical bug related to garbage collection that can lead to internal Hashes being freed and replaced by Strings, causing runtime errors. The author explores the implications of missing write barriers in the FFI C extension.

Puts debugging is a favored technique for many Rails developers, and this article introduces a custom gem called `dbg-rb`, inspired by Rust's `dbg!` macro. It provides enhanced output for debugging by showing variable names, file locations, and line numbers, making the process more efficient without cluttering the Gemfile. Tips for integrating `dbg-rb` into Rails without adding it to the Gemfile are also discussed.