# NO_DOCUMENT_WRITE

Calls to `document.write()` or `document.writeln()` manipulate DOM directly without any sanitization and should be avoided.

Furthermore, these APIs can also cause performance issues and trigger will clear the page contents if used after page load.

## How to fix

Avoid usage of `document.write()` entirely in your application, and instead either use UI framework like React to handle writing to the document,
or use safer DOM APIs, such as `document.createElement()` instead.


--------------------------------------------------------------------------------
title: "NO_EVAL"
description: "Prevent unsafe usage of eval() in your application."
last_updated: "2026-02-03T02:58:39.282Z"
source: "https://vercel.com/docs/conformance/rules/NO_EVAL"
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