Tips for improving your Elixir configuration

Elixir's configuration system has evolved significantly, addressing longstanding challenges and introducing improvements in recent versions to enhance runtime flexibility and reduce reliance on compile-time configurations. Historically, Elixir applications often used compile-time configurations, which posed challenges such as requiring recompilation upon configuration changes and creating difficulties in managing secrets across deployment environments. Over time, the Elixir community has shifted towards runtime configurations, with updates in Elixir 1.9 to 1.11 introducing new mechanisms like `config/runtime.exs` to facilitate this. These changes promote better practices by avoiding the pitfalls of compile-time configurations, such as race conditions in tests and environment-specific releases. Modern approaches encourage the use of runtime configurations, often leveraging tools like dotenv_parser for development, and advocate for localizing configurations to their usage context. While this transition offers benefits like environment-agnostic releases and more reliable handling of environment variables, it also necessitates thoughtful management in complex projects, often through configuration helpers and separate runtime configuration files for different environments.