mirror of
https://github.com/ryan4yin/nixos-and-flakes-book.git
synced 2025-08-23 02:10:20 +02:00
chore: automatically collapse all lines(max width = 100) (#126)
This commit is contained in:
Ryan Yin
GitHub
@@ -3,17 +3,33 @@
|
||||
## Advantages of NixOS
|
||||
|
||||
- **Declarative Configuration, OS as Code**
|
||||
- NixOS uses declarative configuration to manage the entire system environment. These configurations can be managed directly with Git, allowing the system to be restored to any historical state as long as the configuration files are preserved (provided the desired states are declared in the Nix configuration).
|
||||
- Nix Flakes further enhance reproducibility by utilizing a `flake.lock` version lock file, which records the data source addresses, hash values, and other relevant information for all dependencies. This design greatly improves Nix's reproducibility and ensures consistent build results. It draws inspiration from package management designs in programming languages like Cargo and npm.
|
||||
- NixOS uses declarative configuration to manage the entire system environment. These
|
||||
configurations can be managed directly with Git, allowing the system to be restored to
|
||||
any historical state as long as the configuration files are preserved (provided the
|
||||
desired states are declared in the Nix configuration).
|
||||
- Nix Flakes further enhance reproducibility by utilizing a `flake.lock` version lock
|
||||
file, which records the data source addresses, hash values, and other relevant
|
||||
information for all dependencies. This design greatly improves Nix's reproducibility
|
||||
and ensures consistent build results. It draws inspiration from package management
|
||||
designs in programming languages like Cargo and npm.
|
||||
- **Highly Convenient System Customization Capability**
|
||||
- With just a few configuration changes, various components of the system can be easily replaced. Nix encapsulates all the underlying complex operations within Nix packages, providing users with a concise set of declarative parameters.
|
||||
- Modifications are safe and switching between different desktop environments (such as GNOME, KDE, i3, and sway) is straightforward, with minimal pitfalls.
|
||||
- With just a few configuration changes, various components of the system can be easily
|
||||
replaced. Nix encapsulates all the underlying complex operations within Nix packages,
|
||||
providing users with a concise set of declarative parameters.
|
||||
- Modifications are safe and switching between different desktop environments (such as
|
||||
GNOME, KDE, i3, and sway) is straightforward, with minimal pitfalls.
|
||||
- **Rollback Capability**
|
||||
- It is possible to roll back to any previous system state, and NixOS even includes all old versions in the boot options by default, ensuring the ability to easily revert changes. Consequently, Nix is regarded as one of the most stable package management approaches.
|
||||
- It is possible to roll back to any previous system state, and NixOS even includes all
|
||||
old versions in the boot options by default, ensuring the ability to easily revert
|
||||
changes. Consequently, Nix is regarded as one of the most stable package management
|
||||
approaches.
|
||||
- **No Dependency Conflict Issues**
|
||||
- Each software package in Nix has a unique hash, which is incorporated into its installation path, allowing multiple versions to coexist.
|
||||
- Each software package in Nix has a unique hash, which is incorporated into its
|
||||
installation path, allowing multiple versions to coexist.
|
||||
- **The community is active, with a diverse range of third-party projects**
|
||||
- The official package repository, nixpkgs, has numerous contributors, and many people share their Nix configurations. Exploring the NixOS ecosystem is an exciting experience, akin to discovering a new continent.
|
||||
- The official package repository, nixpkgs, has numerous contributors, and many people
|
||||
share their Nix configurations. Exploring the NixOS ecosystem is an exciting
|
||||
experience, akin to discovering a new continent.
|
||||
|
||||
<figure>
|
||||
<img src="/nixos-bootloader.avif">
|
||||
@@ -31,23 +47,51 @@
|
||||
## Disadvantages of NixOS
|
||||
|
||||
- **High Learning Curve**:
|
||||
- Achieving complete reproducibility and avoiding pitfalls associated with improper usage requires learning about Nix's entire design and managing the system declaratively, rather than blindly using commands like `nix-env -i` (similar to `apt-get install`).
|
||||
- Achieving complete reproducibility and avoiding pitfalls associated with improper
|
||||
usage requires learning about Nix's entire design and managing the system
|
||||
declaratively, rather than blindly using commands like `nix-env -i` (similar to
|
||||
`apt-get install`).
|
||||
- **Disorganized Documentation**:
|
||||
- Currently, Nix Flakes remains an experimental feature, and there is limited documentation specifically focused on it. Most Nix community documentation primarily covers the classic `/etc/nixos/configuration.nix`. If you want to start learning directly from Nix Flakes(`flake.nix`), you need to refer to a significant amount of outdated documentation and extract the relevant information. Additionally, some core features of Nix, such as `imports` and the Nixpkgs Module System, lack detailed official documentation, requiring resorting to source code analysis.
|
||||
- Currently, Nix Flakes remains an experimental feature, and there is limited
|
||||
documentation specifically focused on it. Most Nix community documentation primarily
|
||||
covers the classic `/etc/nixos/configuration.nix`. If you want to start learning
|
||||
directly from Nix Flakes(`flake.nix`), you need to refer to a significant amount of
|
||||
outdated documentation and extract the relevant information. Additionally, some core
|
||||
features of Nix, such as `imports` and the Nixpkgs Module System, lack detailed
|
||||
official documentation, requiring resorting to source code analysis.
|
||||
- **Increased Disk Space Usage**:
|
||||
- To ensure the ability to roll back the system at any time, Nix retains all historical environments by default, resulting in increased disk space usage.
|
||||
- While this additional space usage may not be a concern on desktop computers, it can become problematic on resource-constrained cloud servers.
|
||||
- To ensure the ability to roll back the system at any time, Nix retains all historical
|
||||
environments by default, resulting in increased disk space usage.
|
||||
- While this additional space usage may not be a concern on desktop computers, it can
|
||||
become problematic on resource-constrained cloud servers.
|
||||
- **Obscure Error Messages**:
|
||||
- Due to the [complex merging algorithm](https://discourse.nixos.org/t/best-resources-for-learning-about-the-nixos-module-system/1177/4) of the [Nixpkgs module system](../other-usage-of-flakes/module-system.md), NixOS error messages are quite poor. In many cases, regardless of whether you add `--show-trace`, it will only tell you that there is an error in the code (the most common and confusing error message is [Infinite recursion encountered](https://discourse.nixos.org/t/infinite-recursion-encountered-by-making-module-configurable/23508/2)), but where exactly is the error? The type system says it doesn't know, so you have to find it yourself. In my experience, **the simplest and most effective way to deal with these meaningless error messages is to use a "binary search" to gradually restore the code**.
|
||||
- Due to the
|
||||
[complex merging algorithm](https://discourse.nixos.org/t/best-resources-for-learning-about-the-nixos-module-system/1177/4)
|
||||
of the [Nixpkgs module system](../other-usage-of-flakes/module-system.md), NixOS error
|
||||
messages are quite poor. In many cases, regardless of whether you add `--show-trace`,
|
||||
it will only tell you that there is an error in the code (the most common and
|
||||
confusing error message is
|
||||
[Infinite recursion encountered](https://discourse.nixos.org/t/infinite-recursion-encountered-by-making-module-configurable/23508/2)),
|
||||
but where exactly is the error? The type system says it doesn't know, so you have to
|
||||
find it yourself. In my experience, **the simplest and most effective way to deal with
|
||||
these meaningless error messages is to use a "binary search" to gradually restore the
|
||||
code**.
|
||||
- This problem is probably the biggest pain point of NixOS at the moment.
|
||||
- **More Complex Underlying Implementation**:
|
||||
- Nix's declarative abstraction introduces additional complexity in the underlying code compared to similar code in traditional imperative tools.
|
||||
- This complexity increases implementation difficulty and makes it more challenging to make custom modifications at the lower level. However, this burden primarily falls on Nix package maintainers, as regular users have limited exposure to the underlying complexities, reducing their burden.
|
||||
- Nix's declarative abstraction introduces additional complexity in the underlying code
|
||||
compared to similar code in traditional imperative tools.
|
||||
- This complexity increases implementation difficulty and makes it more challenging to
|
||||
make custom modifications at the lower level. However, this burden primarily falls on
|
||||
Nix package maintainers, as regular users have limited exposure to the underlying
|
||||
complexities, reducing their burden.
|
||||
|
||||
## Summary
|
||||
|
||||
Overall, I believe that NixOS is suitable for developers with a certain level of Linux usage experience and programming knowledge who desire greater control over their systems.
|
||||
Overall, I believe that NixOS is suitable for developers with a certain level of Linux
|
||||
usage experience and programming knowledge who desire greater control over their systems.
|
||||
|
||||
I do not recommend newcomers without any Linux usage experience to dive directly into NixOS, as it may lead to a frustrating journey.
|
||||
I do not recommend newcomers without any Linux usage experience to dive directly into
|
||||
NixOS, as it may lead to a frustrating journey.
|
||||
|
||||
> If you have more questions about NixOS, you can refer to the last chapter of this book, [FAQ](../faq/).
|
||||
> If you have more questions about NixOS, you can refer to the last chapter of this book,
|
||||
> [FAQ](../faq/).
|
||||
|
||||
@@ -2,34 +2,77 @@
|
||||
|
||||
# Introduction to Nix & NixOS
|
||||
|
||||
Nix is a declarative package manager that enables users to declare the desired system state in configuration files (declarative configuration), and it takes responsibility for achieving that state.
|
||||
Nix is a declarative package manager that enables users to declare the desired system
|
||||
state in configuration files (declarative configuration), and it takes responsibility for
|
||||
achieving that state.
|
||||
|
||||
> In simple terms, "declarative configuration" means that users only need to declare the desired outcome. For instance, if you declare that you want to replace the i3 window manager with sway, Nix will assist you in achieving that goal. You don't have to worry about the underlying details, such as which packages sway requires for installation, which i3-related packages need to be uninstalled, or the necessary adjustments to system configuration and environment variables for sway. Nix automatically handles these details for the user (provided that the Nix packages related to sway and i3 are properly designed).
|
||||
> In simple terms, "declarative configuration" means that users only need to declare the
|
||||
> desired outcome. For instance, if you declare that you want to replace the i3 window
|
||||
> manager with sway, Nix will assist you in achieving that goal. You don't have to worry
|
||||
> about the underlying details, such as which packages sway requires for installation,
|
||||
> which i3-related packages need to be uninstalled, or the necessary adjustments to system
|
||||
> configuration and environment variables for sway. Nix automatically handles these
|
||||
> details for the user (provided that the Nix packages related to sway and i3 are properly
|
||||
> designed).
|
||||
|
||||
NixOS, a Linux distribution built on top of the Nix package manager, can be described as "OS as Code." It employs declarative Nix configuration files to describe the entire state of the operating system.
|
||||
NixOS, a Linux distribution built on top of the Nix package manager, can be described as
|
||||
"OS as Code." It employs declarative Nix configuration files to describe the entire state
|
||||
of the operating system.
|
||||
|
||||
An operating system consists of various software packages, configuration files, and text/binary data, all of which represent the current state of the system. Declarative configuration can manage only the static portion of this state. Dynamic data, such as PostgreSQL, MySQL, or MongoDB data, cannot be effectively managed through declarative configuration (it is not feasible to delete all new PostgreSQL data that is not declared in the configuration during each deployment).
|
||||
Therefore, **NixOS primarily focuses on managing the static portion of the system state in a declarative manner**.
|
||||
Dynamic data, along with the contents in the user's home directory, remain unaffected by NixOS when rolling back to a previous generation.
|
||||
An operating system consists of various software packages, configuration files, and
|
||||
text/binary data, all of which represent the current state of the system. Declarative
|
||||
configuration can manage only the static portion of this state. Dynamic data, such as
|
||||
PostgreSQL, MySQL, or MongoDB data, cannot be effectively managed through declarative
|
||||
configuration (it is not feasible to delete all new PostgreSQL data that is not declared
|
||||
in the configuration during each deployment). Therefore, **NixOS primarily focuses on
|
||||
managing the static portion of the system state in a declarative manner**. Dynamic data,
|
||||
along with the contents in the user's home directory, remain unaffected by NixOS when
|
||||
rolling back to a previous generation.
|
||||
|
||||
Although we cannot achieve complete system reproducibility, the `/home` directory, being an important user directory, contains many necessary configuration files - [Dotfiles](https://wiki.archlinux.org/title/Dotfiles). A significant community project called [home-manager](https://github.com/nix-community/home-manager) is designed to manage user-level packages and configuration files within the user's home directory.
|
||||
Although we cannot achieve complete system reproducibility, the `/home` directory, being
|
||||
an important user directory, contains many necessary configuration files -
|
||||
[Dotfiles](https://wiki.archlinux.org/title/Dotfiles). A significant community project
|
||||
called [home-manager](https://github.com/nix-community/home-manager) is designed to manage
|
||||
user-level packages and configuration files within the user's home directory.
|
||||
|
||||
Due to Nix's features, such as being declarative and reproducible, Nix is not limited to managing desktop environments but is also extensively used for managing development environments, compilation environments, cloud virtual machines, and container image construction. [NixOps](https://github.com/NixOS/nixops) (an official Nix project) and [colmena](https://github.com/zhaofengli/colmena) (a community project) are both operational tools based on Nix.
|
||||
Due to Nix's features, such as being declarative and reproducible, Nix is not limited to
|
||||
managing desktop environments but is also extensively used for managing development
|
||||
environments, compilation environments, cloud virtual machines, and container image
|
||||
construction. [NixOps](https://github.com/NixOS/nixops) (an official Nix project) and
|
||||
[colmena](https://github.com/zhaofengli/colmena) (a community project) are both
|
||||
operational tools based on Nix.
|
||||
|
||||
## Why NixOS?
|
||||
|
||||
I first learned about the Nix package manager several years ago. It utilizes the Nix language to describe system configuration. NixOS, the Linux distribution built on top of it, allows for rolling back the system to any previous state (although only the state declared in Nix configuration files can be rolled back). While it sounded impressive, I found it troublesome to learn a new language and write code to install packages, so I didn't pursue it at the time.
|
||||
I first learned about the Nix package manager several years ago. It utilizes the Nix
|
||||
language to describe system configuration. NixOS, the Linux distribution built on top of
|
||||
it, allows for rolling back the system to any previous state (although only the state
|
||||
declared in Nix configuration files can be rolled back). While it sounded impressive, I
|
||||
found it troublesome to learn a new language and write code to install packages, so I
|
||||
didn't pursue it at the time.
|
||||
|
||||
However, I recently encountered numerous environmental issues while using EndeavourOS, and resolving them consumed a significant amount of my energy, leaving me exhausted. Upon careful consideration, I realized that the lack of version control and rollback mechanisms in EndeavourOS prevented me from restoring the system when problems arose.
|
||||
However, I recently encountered numerous environmental issues while using EndeavourOS, and
|
||||
resolving them consumed a significant amount of my energy, leaving me exhausted. Upon
|
||||
careful consideration, I realized that the lack of version control and rollback mechanisms
|
||||
in EndeavourOS prevented me from restoring the system when problems arose.
|
||||
|
||||
That's when I decided to switch to NixOS.
|
||||
|
||||
To my delight, NixOS has exceeded my expectations. The most astonishing aspect is that I can now restore my entire i3 environment and all my commonly used packages on a fresh NixOS host with just one command `sudo nixos-rebuild switch --flake .`. It's truly fantastic!
|
||||
To my delight, NixOS has exceeded my expectations. The most astonishing aspect is that I
|
||||
can now restore my entire i3 environment and all my commonly used packages on a fresh
|
||||
NixOS host with just one command `sudo nixos-rebuild switch --flake .`. It's truly
|
||||
fantastic!
|
||||
|
||||
The rollback capability and reproducibility of NixOS has instilled a great deal of confidence in me—I no longer fear breaking the system. I've even ventured into experimenting with new things on NixOS, such as the hyprland compositor. Previously, on EndeavourOS, I wouldn't have dared to tinker with such novel compositors, as any system mishaps would have entailed significant manual troubleshooting using various workarounds.
|
||||
The rollback capability and reproducibility of NixOS has instilled a great deal of
|
||||
confidence in me—I no longer fear breaking the system. I've even ventured into
|
||||
experimenting with new things on NixOS, such as the hyprland compositor. Previously, on
|
||||
EndeavourOS, I wouldn't have dared to tinker with such novel compositors, as any system
|
||||
mishaps would have entailed significant manual troubleshooting using various workarounds.
|
||||
|
||||
As I get more and more involved with NixOS and Nix, I find it also very suitable for synchronously managing the configuration of multiple hosts.
|
||||
Currently my personal [nix-config](https://github.com/ryan4yin/nix-config) synchronously manages the configuration of many hosts:
|
||||
As I get more and more involved with NixOS and Nix, I find it also very suitable for
|
||||
synchronously managing the configuration of multiple hosts. Currently my personal
|
||||
[nix-config](https://github.com/ryan4yin/nix-config) synchronously manages the
|
||||
configuration of many hosts:
|
||||
|
||||
- Desktop computers
|
||||
- 1 Macbook Pro 2020 (Intel amd64).
|
||||
@@ -39,7 +82,9 @@ Currently my personal [nix-config](https://github.com/ryan4yin/nix-config) synch
|
||||
- 3 NixOS virtual machines (amd64).
|
||||
- Several development boards for aarch64 and riscv64.
|
||||
|
||||
The development environment of three desktop computers is managed by Home Manager,
|
||||
the main configuration is completely shared, and the configuration modified on any host can be seamlessly synchronized to other hosts through Git.
|
||||
The development environment of three desktop computers is managed by Home Manager, the
|
||||
main configuration is completely shared, and the configuration modified on any host can be
|
||||
seamlessly synchronized to other hosts through Git.
|
||||
|
||||
Nix almost completely shielded me from the differences between OS and architecture at the bottom of the three machines, and the experience was very slippery!
|
||||
Nix almost completely shielded me from the differences between OS and architecture at the
|
||||
bottom of the three machines, and the experience was very slippery!
|
||||
|
||||
@@ -3,11 +3,17 @@
|
||||
Nix can be installed in various ways:
|
||||
|
||||
1. As a package manager on macOS, Linux, or WSL.
|
||||
2. As the system environment manager on NixOS, a Linux distribution that utilizes Nix for system management.
|
||||
2. As the system environment manager on NixOS, a Linux distribution that utilizes Nix for
|
||||
system management.
|
||||
|
||||
This book primarily focuses on the usage of NixOS and Flakes. Therefore, we will skip content that pertains solely to Nix(such as installation on macOS, Linux, or WSL).
|
||||
This book primarily focuses on the usage of NixOS and Flakes. Therefore, we will skip
|
||||
content that pertains solely to Nix(such as installation on macOS, Linux, or WSL).
|
||||
|
||||
The installation process of NixOS is straightforward, but we won't delve into the specifics here. For more information, please visit the official download site at <https://nixos.org/download.html>.
|
||||
The installation process of NixOS is straightforward, but we won't delve into the
|
||||
specifics here. For more information, please visit the official download site at
|
||||
<https://nixos.org/download.html>.
|
||||
|
||||
> If you're using macOS, [ryan4yin/nix-darwin-kickstarter](https://github.com/ryan4yin/nix-darwin-kickstarter) may be a good starting point for you,
|
||||
> you can learn how to use Nix with this book and take nix-darwin-kickstarter as a start point to build your own Nix configuration.
|
||||
> If you're using macOS,
|
||||
> [ryan4yin/nix-darwin-kickstarter](https://github.com/ryan4yin/nix-darwin-kickstarter)
|
||||
> may be a good starting point for you, you can learn how to use Nix with this book and
|
||||
> take nix-darwin-kickstarter as a start point to build your own Nix configuration.
|
||||
|
||||
Reference in New Issue
Block a user