Execution order defined

When multiple plugins register handlers for the same hook and execution order is undefined or depends on object property enumeration, plugin behavior becomes non-deterministic across JavaScript engines and load sequences. An auth plugin that must run before a logging plugin cannot declare that requirement. Debugging a production incident caused by handler ordering requires understanding internal host iteration behavior rather than a declared contract. ISO 25010 maintainability.modularity requires that component interactions be predictable; undefined execution order breaks this at the seam between every plugin pair.

Expose an explicit ordering mechanism — either a numeric priority parameter or a dependency-based after declaration — on every hook registration call. Document which strategy the system uses so plugin authors can predict relative execution.

// Priority-based ordering:
registry.on('before:save', handler, { priority: 10 }); // lower = earlier

// Or dependency-based:
registry.on('before:save', handler, { after: ['auth-plugin'] });