interface User {
 children?: User;
 email: `${string}@${string}`;
 password: string;
}

import * as v from 'valibot';

const EmailSchema = v.string([v.minLength(1), v.email()]);
const PasswordSchema = v.string([v.minLength(1), v.minLength(8)]);
// const UserSchema?

type UserSchemaType = {
 children?: UserSchemaType;
 email: v.Input<typeof EmailSchema>;
 password: v.Input<typeof PasswordSchema>;
}

const UserSchema: v.BaseSchema<UserSchemaType> = v.object({
 children: v.optional(v.lazy(() => UserSchema)),
 email: EmailSchema,
 password: PasswordSchema,
});