next-safe-actionIntroduction
next-safe-action is a library that takes the hassle out of Server Actions in Next.js. It gives you end-to-end type safety from input validation to the action result, with a chainable API for middleware, metadata, and schema validation, all powered by Standard Schema.
Features
Type Safety
Full TypeScript inference from input schema to action result, no manual type annotations needed.
Validation
Built-in input and output validation via Standard Schema (Zod, Valibot, ArkType, and more).
Middleware
Chainable middleware with type-safe context accumulation for authentication, logging, and more.
React Hooks
Purpose-built hooks for executing actions with status tracking, callbacks, and optimistic updates.
Why next-safe-action?
Server Actions are powerful, but using them directly means writing a lot of boilerplate for validation, error handling, and type safety. Here's what changes with next-safe-action.
Without next-safe-action, raw Server Actions have no built-in validation or typed results:
"use server";
export async function updateUser(formData: FormData) {
// ❌ No type safety — raw FormData
const name = formData.get("name");
// ❌ Manual validation
if (typeof name !== "string" || name.length < 3) {
return { error: "Invalid name" };
}
// ❌ Untyped result — caller doesn't know the shape
try {
await db.user.update({ name });
return { success: true };
} catch (e) {
return { error: "Something went wrong" };
}
}With next-safe-action, validation, type safety, and structured results out of the box:
"use server";
import { z } from "zod";
import { actionClient } from "@/lib/safe-action";
export const updateUser = actionClient
.inputSchema(z.object({ name: z.string().min(3) }))
.action(async ({ parsedInput: { name } }) => {
// ✅ `name` is typed as `string`, validated, min 3 chars
await db.user.update({ name });
// ✅ Return type is inferred and available to the caller
return { success: true };
});The result is always a structured object with data, validationErrors, and serverError, making it impossible to forget error handling on the client side.
Requirements
- Next.js >= 14
- React >= 18.2.0
- TypeScript >= 5
- A validation library supported by Standard Schema (e.g., Zod, Valibot, ArkType)