# Ktor: Altering served content DevFeed: [Ktor: Altering served content]() Original publisher: [Read original article]() Author: Marc Plano-Lesay Published: 2022-09-06T04:00:00Z Content type: tutorial Language: en Sources: [Marc Plano-Lesay]() Topics: [Web Development](), [Netty](), [HTTP](), [servers]() Tags: [configuration](), [html](), [http](), [js](), [kotlin](), [ktor](), [plugin](), [plugins](), [script](), [server](), [web]() ## AI overview A tutorial on creating a Ktor plugin that injects a configured script element into the head of served HTML files. It uses Ktor response-pipeline hooks to transform HTML while leaving other file formats unchanged, with Jsoup handling the HTML modification. ## Source excerpt When serving files with Ktor, there might be times when you need to alter those files. For example, you might want to inject a script in every served HTML file. For this purpose, we can leverage plugins. Plugins can hook at different stages of the request/response pipeline: graph LR Request --> Plugin1[Plugin] Plugin1 --> Handler Handler --> Plugin2[Plugin] Plugin2 --> Response Ktor request/response pipeline Let's write a plugin that transforms a specific type of files - going with the previous example of injecting a script to every served HTML file. Our plugin needs to: Take a script URL as an input. If not provided, it won't do anything. Add that script as a