@pyreon/validate

Pyreon's validator + Standard Schema DX layer — field metadata, reactive parse, i18n-aware error formatting, and (since v1) Pyreon's own validator runtime.

Standard Schema (https://standardschema.dev) is the cross-library protocol implemented natively by Zod 3.24+, Valibot 1.0+, ArkType 2.0+, and any future spec-compliant validator. @pyreon/validate adds the things the spec deliberately omits, plus Pyreon-native bridges to @pyreon/reactivity and @pyreon/i18n.

Two ways to use it:

1. DX helpers on top of your validator of choice (Zod / Valibot / ArkType). The Pyreon validator runtime tree-shakes away entirely — a DX-helpers-only import is ~0.5KB gz (measured).
2. Pyreon's own s validator (v1) — chainable + function-comp hybrid, Standard Schema-native, ~3.5KB gz when imported. No third-party validator needed.

bun add @pyreon/validate
# Option 1 — pair the DX helpers with a third-party validator:
bun add zod          # or
bun add valibot      # or
bun add arktype
# Option 2 — use Pyreon's own `s` validator (no extra dep):
#   import { s } from '@pyreon/validate'

Quick start

import { z } from 'zod'
import { signal } from '@pyreon/reactivity'
import { useI18n } from '@pyreon/i18n'
import { withField, parseReactive, formatErrors, watchValid } from '@pyreon/validate'

// 1. Attach metadata.
const emailSchema = withField(z.string().email(), {
  label: 'Email address',
  placeholder: '[email protected]',
  hint: 'We never share your email',
  i18nLabel: 'auth.email.label',
})

// 2. Reactively validate as the user types.
const $email = signal('')
const $result = parseReactive(emailSchema, $email)

// 3. Format errors with i18n.
const { t } = useI18n()
effect(() => {
  const r = $result()
  if (r.issues) showErrors(formatErrors(r.issues, t))
})

// 4. Subscribe only to validity flips.
const stop = watchValid(emailSchema, $email, (valid) => {
  submitButton.disabled = !valid
})

API surface (v1)

| Helper | Purpose | | --- | --- | | withField(schema, meta) | Attach FieldMeta (label, hint, placeholder, i18n keys, autoFocus, autoComplete) to any Standard Schema. Returns the same reference — metadata is a Symbol-keyed non-enumerable slot. | | getMeta(schema) | Read attached metadata back. Returns undefined for unwrapped schemas. | | resolveMetaField(schema, field, t?) | Read a field through optional i18n. t('auth.email.label') wins over meta.label when it resolves. | | parseReactive(schema, source) | Computed<ParseResult> that re-derives on signal changes. Synchronous. | | parseReactiveAsync(schema, source) | Async variant for schemas with async refinements. | | watchValid(schema, source, cb) | Fire cb(valid) only on validity transitions, not every error change. | | formatError(issue, t?) | Resolve a single issue's text. issue.key + t wins; falls back to fallback then message. | | formatErrors(issues, t?) | Array variant. | | formatErrorsByPath(issues, t?, options?) | Build a per-field error map keyed by the issue's path. Compatible with @pyreon/form's Errors shape. |

Why mutate-in-place?

withField() mutates the original schema with a Symbol-keyed non-enumerable property. It does NOT clone.

ArkType's Type instances are callable functions whose ~standard.validate does this(input) — this must be the callable schema itself. A shallow clone (Object.create()) is not callable and breaks that contract. Symbol-keyed non-enumerable mutation is invisible to:

• JSON.stringify (skips symbol keys)
• for…in / Object.keys / Object.entries
• Structured clone
• Library-internal schema comparators

…so the mutation is functionally hidden. Re-wrapping is the natural extension — withField(base, { a }) then withField(base, { b }) produces a schema with both a and b automatically.

What this is NOT

• A new validator. Use Zod / Valibot / ArkType / typia. @pyreon/validate makes them Pyreon-flavoured.
• A validation library you must adopt. Existing zodSchema / valibotSchema / arktypeSchema adapters from @pyreon/validation continue to work.
• A perf claim. v1 parse speed is the underlying lib's speed. A follow-up PR adds @pyreon/compiler:analyzeValidate() for typia-class wall-clock per schema (works against any Standard Schema validator).

See also

• Standard Schema spec
• @pyreon/validation — per-lib adapters for @pyreon/form
• @pyreon/form — signal-based forms
• @pyreon/i18n — translation provider