nginx.org C Module Directive Design Best Practices

Comprehensive directive design guide for nginx C module authors, focused on creating clear, consistent, and admin-friendly configuration interfaces. Contains 46 rules across 8 categories, prioritized by impact to guide decisions about what to expose, how to name it, and how to evolve it safely.

When to Apply

Reference these guidelines when:

• Deciding which values to expose as directives vs hardcode
• Naming new directives and choosing argument types
• Selecting scope placement (http, server, location)
• Setting default values and validation behavior
• Designing nginx variables for runtime data
• Deprecating or renaming existing directives

Companion Skills