nixos-demo/slides/demo.md

---
author: Birk
---

# Nix(OS)

a introduction 

---

## What is Nix?

* a domain specific language
* a package manager
* a Linux distribution

---

```mermaid
%%{init: {'theme': 'dark', 'themeVariables': { 'darkMode': true }}}%%
flowchart LR
    A(Nix language) 
    B(Nix package manager)
    C(NixOS)
    D(macOS)
    E(Debian)
    F(Software/User config)
    G(Git)
    H(File)
    A-->B--->C & D & E---->F --> G & H
```

---

## Demo

```mermaid
%%{init: {'theme': 'dark', 'themeVariables': { 'darkMode': true }}}%%
flowchart TD
        B(<b>Disk & OS Installation)
        C(<b>Desktop)
        D(Nextcloud server)
        E(nspawn container)
        F(Gitlab server)
        G(Podman container)
        H(Forgejo)
        I(MicroVM)
        J(Kubernetes)
        K(Splunk)
        B--> D & E & G & I
        B-->C
        E-->F
        G-->H
        I-->J-->K
```

---

## History

- 2003: [a declarative programming language](https://www.youtube.com/watch?v=fsgYVi2PQr0)
- 2008: first stable NixOS version
- 2014: 10.000 packages
- 2019: Flakes
- 2025: [120.000 packages](https://repology.org/repositories/graphs)

---

## Features

- [declarative configuration](https://search.nixos.org/options?) (20.000 options) 
- [package](https://search.nixos.org/packages) count (120.000 + third party)
- Development community on Github and other hosters

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## Infrastructure

- [nixpkgs](https://github.com/NixOS/nixpkgs) on Github
- [nix language](https://github.com/NixOS/nix) on Github
- [Binary cache](https://cache.nixos.org/) for built packages
- [CI server](https://hydra.nixos.org/)
- [Build status](https://status.nixos.org/) page
- ...

---

## Nextcloud

```mermaid
%%{init: {'theme': 'dark', 'themeVariables': { 'darkMode': true }}}%%
flowchart TD
        B(Disk & OS Installation)
        C[services.nextcloud.enable=true]
        D(<b>Nextcloud server)
        E[services.nextcloud.package=nextcloud30]
        B--> D
        D-->C & E
```

---

## Gitlab

```mermaid
%%{init: {'theme': 'dark', 'themeVariables': { 'darkMode': true }}}%%
flowchart TD
        B(<b>Disk & OS Installation)
        E(nspawn container)
        F(<b>Gitlab server)
        G[services.gitlab.enable=true]
        H[services.gitlab.backup.startAt=03:00]
        I[services.nginx.enable=true]
        B--> E --> F
        F-->G & H & I
```

---

## Forgejo

```mermaid
%%{init: {'theme': 'dark', 'themeVariables': { 'darkMode': true }}}%%
flowchart LR
        B(<b>Disk & OS Installation)
        G(Podman container)
        H(<b>Forgejo)
        I[virtualisation.containers.enable=true]
        J[virtualisation.oci-containers.containers.forgejo-frontend.image=codeberg.org/forgejo/forgejo:11.0.3-rootless]
        K[forgejo-backend.image=docker.io/library/mariadb:11.8.2]
        B --> I --> G  --> H --> J & K
```

---

## Splunk

```mermaid
%%{init: {'theme': 'dark', 'themeVariables': { 'darkMode': true }}}%%
flowchart LR
    subgraph pc-demo1
        direction LR
        B(<b>Disk & OS Installation)
        subgraph k8s
            direction LR
            I("MicroVM(NixOS)")
            J(Kubernetes)
            subgraph containerd
                direction LR
                L(Container)
                K(<b>Splunk)
            end
        end
    end
    B--> I --> J --> L --> K
```

---

## Unexpected stuff

- Flakes are not stable yet, but everybody uses them
- Documentation quality has room for improvement
- Additional efforts for secrets management
- Does not follow Linux Filesystem Hierarchy Standard
- Commercial software usage can be tricky or impossible