Installation

Seal is standalone — no framework required. Inside a Warlock app it ships transitively through @warlock.js/core, so if you’re already on core you can import v directly without installing anything. Otherwise, add it with your package manager:

npm

npm install @warlock.js/seal

yarn

yarn add @warlock.js/seal

pnpm

pnpm add @warlock.js/seal

Seal has two runtime dependencies (@mongez/supportive-is and dayjs), both pulled in transitively. No peer dependencies to install separately.

Use it directly

Import the v factory, validate, and the Infer type helper — no framework primitives required:

import { v, validate, type Infer } from "@warlock.js/seal";

const userSchema = v.object({
  email: v.string().email(),
  name: v.string().min(2),
});

type User = Infer<typeof userSchema>;

const result = await validate(userSchema, { email: "ada@example.com", name: "Ada" });

if (result.isValid) {
  console.log(result.data); // typed as User
} else {
  console.error(result.errors);
}

Inside a Warlock app, the same schema slots into any StandardSchemaV1<T>-typed slot — request validation, AI tool input, Cascade Model.schema — because every seal schema implements Standard Schema. New to Warlock? Start with core / getting-started.

Global configuration (optional)

For centralized translation hooks or to collect every error instead of the first per field, configure once at boot:

import { configureSeal } from "@warlock.js/seal";

configureSeal({
  firstErrorOnly: false, // collect every error, not just the first per field
  translateRule: ({ rule, attributes }) => {
    // Hook into your i18n layer; return the localized message.
    return t(`validation.${rule.name}`, attributes);
  },
});

firstErrorOnly defaults to true — most apps surface one error per field at a time, which keeps the response payload small.

Verify the install

Drop this into a tsx file or a script and run it:

import { v, validate } from "@warlock.js/seal";

const schema = v.string().email();
const result = await validate(schema, "ada@example.com");

console.log(result.isValid); // true
console.log(result.data);    // "ada@example.com"

If that prints true and the email back, you’re set.

Next

Your first schema — the full define → validate → infer → emit-JSON-Schema loop in one runnable example.