---
title: no-sync
-layout: doc
rule_type: suggestion
---
-This rule was **deprecated** in ESLint v7.0.0. Please use the corresponding rule in [`eslint-plugin-node`](https://github.com/mysticatea/eslint-plugin-node).
+This rule was **deprecated** in ESLint v7.0.0. Please use the corresponding rule in [`eslint-plugin-n`](https://github.com/eslint-community/eslint-plugin-n).
In Node.js, most I/O is done through asynchronous methods. However, there are often synchronous versions of the asynchronous methods. For example, `fs.exists()` and `fs.existsSync()`. In some contexts, using synchronous operations is okay (if, as with ESLint, you are writing a command line utility). However, in other contexts the use of synchronous operations is considered a bad practice that should be avoided. For example, if you are running a high-travel web server on Node.js, you should consider carefully if you want to allow any synchronous operations that could lock up the server.