🆚 Why drea

	drea	Joi	Yup	Zod	AJV
Rule syntax	Plain function, RegExp, or None	Chainable DSL	Chainable DSL	Chainable DSL	JSON Schema spec
TypeScript types	✅ Bundled in v4	Via @types	Via @types	Built-in	Via @types
Type-narrowing guards	✅ asserts value is T	❌	❌	Partial (parse-based)	❌
Dependencies	Zero	Several	Several	Zero	Several
Partial-payload matching	✅ Automatic	Needs .optional()	Needs .optional()	Needs .optional()	Needs "required" array
Runtime schema mutation	extend() remove() swap()	✗	✗	✗	✗
"Expected X, got Y" messages	✅ Every guard	❌	❌	Partial	❌
Recursive nested schemas	nestvalidate()	✅	✅	✅	✅
Skip validation sentinel	✅ None	❌	❌	❌	❌
File validation helper	✅ __File()	❌	❌	❌	❌

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