---
id: ts-schema-validation-comparison
title: Schema 검증 비교 — Zod / Valibot / Effect Schema / ArkType
category: Coding
status: draft
source_trust_level: B
verification_status: conceptual
created_at: 2026-05-09
updated_at: 2026-05-09
tags: [typescript, validation, zod, vibe-coding]
tech_stack: { language: "TS", applicable_to: ["Backend", "Frontend"] }
applied_in: []
aliases: [Zod, Valibot, Effect Schema, ArkType, Yup, runtime validation, schema]
---

# Schema Validation 비교

> Runtime 검증 + TS infer = 표준. **Zod = 가장 일반, Valibot = 작은 bundle, ArkType = 빠르고 syntax 신선, Effect Schema = Effect 사용자**.

## 📖 핵심 개념
- 검증: unknown → typed parse / fail.
- Infer: schema → TS type.
- Refinement: 추가 조건 (email, regex).
- Transform: parse 시 변환.

## 💻 코드 패턴

### Zod (de-facto 표준)
```ts
import { z } from 'zod';

const User = z.object({
  id: z.string().uuid(),
  email: z.string().email(),
  age: z.number().int().positive().optional(),
  role: z.enum(['admin', 'user']).default('user'),
  tags: z.array(z.string()).default([]),
});

type User = z.infer<typeof User>;

const parsed = User.parse(input);    // throws ZodError
const safe = User.safeParse(input);  // { success, data | error }
```

```ts
// transform
const Trimmed = z.string().transform(s => s.trim());

// refine
const StrongPw = z.string().refine(s => s.length >= 8 && /[0-9]/.test(s));

// discriminated union
const Action = z.discriminatedUnion('type', [
  z.object({ type: z.literal('a'), x: z.number() }),
  z.object({ type: z.literal('b'), y: z.string() }),
]);
```

### Valibot (작은 bundle, tree-shakable)
```ts
import * as v from 'valibot';

const User = v.object({
  id: v.pipe(v.string(), v.uuid()),
  email: v.pipe(v.string(), v.email()),
  age: v.optional(v.pipe(v.number(), v.integer(), v.minValue(0))),
});

type User = v.InferOutput<typeof User>;

const parsed = v.parse(User, input);
```

→ Bundle: zod ~13KB vs valibot ~2KB.

### ArkType (빠른 + syntax)
```ts
import { type } from 'arktype';

const User = type({
  id: 'string',
  email: 'email',
  age: 'number > 0?',
  role: '"admin" | "user"',
});

type User = typeof User.infer;

const out = User(input);
if (out instanceof type.errors) console.log(out.summary);
else console.log(out);
```

→ TS-template-literal 기반 — runtime 빠름, dev 시 type 직접 추적.

### Effect Schema
```ts
import { Schema } from 'effect';

const User = Schema.Struct({
  id: Schema.String.pipe(Schema.uuid()),
  email: Schema.String.pipe(Schema.email()),
  age: Schema.Number.pipe(Schema.positive()),
});

const decoded = Schema.decodeUnknownSync(User)(input);
```

→ Effect 와 통합.

### 공통 패턴

#### Form (RHF)
```ts
import { zodResolver } from '@hookform/resolvers/zod';
useForm({ resolver: zodResolver(schema) });
```

#### API (Hono)
```ts
import { zValidator } from '@hono/zod-validator';

app.post('/users', zValidator('json', User), (c) => {
  const data = c.req.valid('json'); // typed
});
```

#### 환경변수
```ts
const Env = z.object({
  DATABASE_URL: z.string().url(),
  PORT: z.coerce.number().default(3000),
  NODE_ENV: z.enum(['dev', 'prod', 'test']),
});

export const env = Env.parse(process.env);
```

#### LLM structured output
```ts
const Recipe = z.object({...});
zodResponseFormat(Recipe, 'recipe'); // OpenAI
zodToJsonSchema(Recipe);              // Anthropic
```

### Migration zod → valibot
```ts
// 비슷한 API — 직접 변경
z.object({ name: z.string() })
v.object({ name: v.string() })

z.string().email()
v.pipe(v.string(), v.email())
```

## 🤔 의사결정 기준
| 상황 | 추천 |
|---|---|
| 일반 (백 + 프론트) | Zod |
| Frontend bundle critical | Valibot |
| 성능 critical (validation hot path) | ArkType |
| Effect 사용 중 | Effect Schema |
| 학습 / 안정성 | Zod |
| Shared backend + frontend | Zod (가장 호환) |

## ❌ 안티패턴
- **검증 없이 unknown 그대로 사용**: 런타임 crash.
- **Zod schema 가 거대 (50+ 필드)**: 분리 + compose.
- **Refinement 안에 외부 fetch**: synchronous expected. transform.
- **`.passthrough()` 디폴트**: extra 키 안 차단. strict.
- **Type 직접 정의 + schema 따로**: drift. infer.
- **Form schema = API schema 직접**: 다를 수 있음 — 분리.
- **zod + 큰 bundle 신경 X**: SSR 만 / API 만 사용.

## 🤖 LLM 활용 힌트
- Zod 가 안전 디폴트.
- Bundle 작아야 = Valibot.
- AI structured output = Zod (OpenAI helper).

## 🔗 관련 문서
- [[AI_Structured_Output_Zod]]
- [[TS_Effect_FP_Patterns]]