# Mastering Nixpkgs Overlays: Techniques and Best Practice

DevFeed: [Mastering Nixpkgs Overlays: Techniques and Best Practice](<https://devfeed.tech/articles/mastering-nixpkgs-overlays-techniques-and-best-practice-32438.md>)

Original publisher: [Read original article](<https://nixcademy.com/posts/mastering-nixpkgs-overlays-techniques-and-best-practice/>)

Author: Jacek Galowicz

Published: 2024-08-01T00:00:00Z

Content type: tutorial

Language: en

Sources: [Nixcademy Blog](<https://devfeed.tech/sources/nixcademy-blog.md>)

Topics: [Nix](<https://devfeed.tech/topics/nix.md>), [function](<https://devfeed.tech/topics/function.md>), [monorepo](<https://devfeed.tech/topics/monorepo.md>), [Open Source](<https://devfeed.tech/topics/open-source.md>), [systems](<https://devfeed.tech/topics/systems.md>), [Fuzzing/Fuzz testing](<https://devfeed.tech/topics/fuzzing.md>), [Testing](<https://devfeed.tech/topics/testing.md>)

Tags: [function](<https://devfeed.tech/tags/function.md>), [fuzzing](<https://devfeed.tech/tags/fuzzing.md>), [how-to](<https://devfeed.tech/tags/how-to.md>), [monorepo](<https://devfeed.tech/tags/monorepo.md>), [open-source](<https://devfeed.tech/tags/open-source.md>), [patches](<https://devfeed.tech/tags/patches.md>), [systems](<https://devfeed.tech/tags/systems.md>), [techniques](<https://devfeed.tech/tags/techniques.md>), [testing](<https://devfeed.tech/tags/testing.md>)

## AI overview

This tutorial explains how Nixpkgs overlays help compose package collections and build different package or system-image variants. It covers the problems overlays solve, how to apply them to package trees and system images, and positive and negative examples.

## Source excerpt

Overlays in Nixpkgs are a powerful mechanism, but they are also complex to grasp. We tell you everything you need to know about Nixpkgs overlays.