topology: add a bunch of non-nixos machines

README.MD

@@ -1,61 +0,0 @@
-# PVV NixOS configs
-
-## Hvordan endre på ting
-
-Før du endrer på ting husk å ikke putte ting som skal være hemmelig uten å først lese seksjonen for hemmeligheter!
-
-Etter å ha klonet prosjektet ned og gjort endringer kan du evaluere configene med:
-
-`nix flake check --keep-going`
-
-før du bygger en maskin med:
-
-`nix build .#<maskinnavn>`
-
-hvis du vil være ekstra sikker på at alt bygger så kan du kjøre:
-
-`nix build .` for å bygge alle de viktige maskinene.
-
-NB: Dette kan ta opp til 30 minutter avhengig av hva som ligger i caches
-
-Husk å hvertfall stage nye filer om du har laget dem!
-
-Om alt bygger fint commit det og push til git repoet.
-Det er sikkert lurt å lage en PR først om du ikke er vandt til nix enda.
-
-Innen 24h skal alle systemene hente ned den nye konfigurasjonen og deploye den.
-
-Du kan tvinge en maskin til å oppdatere seg før dette ved å kjøre:
-`nixos-rebuild switch --update-input nixpkgs --update-input nixpkgs-unstable --no-write-lock-file --refresh --upgrade --flake git+https://git.pvv.ntnu.no/Drift/pvv-nixos-config.git`
-
-som root på maskinen.
-
-Hvis du ikke har lyst til å oppdatere alle pakkene (og kanskje måtte vente en stund!) kan du kjøre
-
-`nixos-rebuild switch --override-input nixpkgs nixpkgs --override-input nixpkgs-unstable nixpkgs-unstable --flake git+https://git.pvv.ntnu.no/Drift/pvv-nixos-config.git`
-
-## Seksjonen for hemmeligheter
-
-For at hemmeligheter ikke skal deles med hele verden i git - eller å være world
-readable i nix-storen, bruker vi [sops-nix](https://github.com/Mic92/sops-nix)
-
-For å legge til secrets kan du kjøre f.eks. `sops secrets/jokum/jokum.yaml`
-Dette vil dekryptere filen og gi deg en text-editor du kan bruke for endre hemmelighetene.
-
-Et nix shell med dette verktøyet inkludert ligger i flaket og shell.nix og kan aktiveres med:
-
-`nix-shell` eller `nix develop`. Vi anbefaler det siste.
-I tilegg kan du sette opp [direnv](https://direnv.net/) slik at dette skjer automatisk
-
-for å få tilgang til å lese/skrive hemmeligheter må du spørre noen/noe som har tilgang til hemmelighetene
-om å legge til age eller pgp nøkkelen din i [`.sops.yaml`](https://git.pvv.ntnu.no/Drift/pvv-nixos-config/src/main/.sops.yaml)
-
-Denne kan du generere fra ssh-nøkkelene dine eller lage en egen nøkkel.
-
-### Legge til flere keys
-
-Gjør det som gir mening i .sops.yml
-
-Etter det kjør `sops updatekeys secrets/host/file.yml`
-
-MERK at det ikke er `sops -r` som BARE roterer nøkklene for de som allerede er i secretfila

README.md

@@ -0,0 +1,36 @@
+# PVV NixOS config
+
+This repository contains the NixOS configurations for Programvareverkstedet's server closet.
+In addition to machine configurations, it also contains a bunch of shared modules, packages, and
+more.
+
+## Machines
+
+| Name                       | Type     | Description                                               |
+|----------------------------|----------|-----------------------------------------------------------|
+| [bekkalokk][bek]           | Physical | Our main web host, webmail, wiki, idp, minecraft map, ... |
+| [bicep][bic]               | Virtual  | Database host, matrix, git mirrors, ...                   |
+|  bikkje                    | Virtual  | Experimental login box                                    |
+| [brzeczyszczykiewicz][brz] | Physical | Shared music player                                       |
+| [georg][geo]               | Physical | Shared music player                                       |
+| [ildkule][ild]             | Virtual  | Logging and monitoring host, prometheus, grafana, ...     |
+| [kommode][kom]             | Virtual  | Gitea + Gitea pages                                       |
+| [lupine][lup]              | Physical | Gitea CI/CD runners                                       |
+|  shark                     | Virtual  | Test host for authentication, absolutely horrendous       |
+| [wenche][wen]              | Virtual  | Nix-builders, general purpose compute                     |
+
+## Documentation
+
+- [Development - working on the PVV machines](./docs/development.md)
+- [Miscellaneous development notes](./docs/development-misc.md)
+- [User management](./docs/users.md)
+- [Secret management and `sops-nix`](./docs/secret-management.md)
+
+[bek]: https://wiki.pvv.ntnu.no/wiki/Maskiner/bekkalokk
+[bic]: https://wiki.pvv.ntnu.no/wiki/Maskiner/bicep
+[brz]: https://wiki.pvv.ntnu.no/wiki/Maskiner/brzęczyszczykiewicz
+[geo]: https://wiki.pvv.ntnu.no/wiki/Maskiner/georg
+[ild]: https://wiki.pvv.ntnu.no/wiki/Maskiner/ildkule
+[kom]: https://wiki.pvv.ntnu.no/wiki/Maskiner/kommode
+[lup]: https://wiki.pvv.ntnu.no/wiki/Maskiner/lupine
+[wen]: https://wiki.pvv.ntnu.no/wiki/Maskiner/wenche

base/default.nix

@@ -25,6 +25,9 @@
     ./services/nginx.nix
     ./services/openssh.nix
     ./services/postfix.nix
+    ./services/prometheus-node-exporter.nix
+    ./services/prometheus-systemd-exporter.nix
+    ./services/promtail.nix
     ./services/smartd.nix
     ./services/thermald.nix
     ./services/userborn.nix

base/services/prometheus-node-exporter.nix

@@ -0,0 +1,23 @@
+{ config, lib, values, ... }:
+let
+  cfg = config.services.prometheus.exporters.node;
+in
+{
+  services.prometheus.exporters.node = {
+    enable = lib.mkDefault true;
+    port = 9100;
+    enabledCollectors = [ "systemd" ];
+  };
+
+  systemd.services.prometheus-node-exporter.serviceConfig = lib.mkIf cfg.enable {
+    IPAddressDeny = "any";
+    IPAddressAllow = [
+      "127.0.0.1"
+      "::1"
+      values.hosts.ildkule.ipv4
+      values.hosts.ildkule.ipv6
+    ];
+  };
+
+  networking.firewall.allowedTCPPorts = lib.mkIf cfg.enable [ cfg.port ];
+}

base/services/prometheus-systemd-exporter.nix

@@ -0,0 +1,26 @@
+{ config, lib, values, ... }:
+let
+  cfg = config.services.prometheus.exporters.systemd;
+in
+{
+  services.prometheus.exporters.systemd = {
+    enable = lib.mkDefault true;
+    port = 9101;
+    extraFlags = [
+      "--systemd.collector.enable-restart-count"
+      "--systemd.collector.enable-ip-accounting"
+    ];
+  };
+
+  systemd.services.prometheus-systemd-exporter.serviceConfig = {
+    IPAddressDeny = "any";
+    IPAddressAllow = [
+      "127.0.0.1"
+      "::1"
+      values.hosts.ildkule.ipv4
+      values.hosts.ildkule.ipv6
+    ];
+  };
+
+  networking.firewall.allowedTCPPorts = lib.mkIf cfg.enable [ cfg.port ];
+}

base/services/promtail.nix

@@ -0,0 +1,38 @@
+{ config, lib, values, ... }:
+let
+  cfg = config.services.prometheus.exporters.node;
+in
+{
+  services.promtail = {
+    enable = lib.mkDefault true;
+    configuration = {
+      server = {
+        http_listen_port = 28183;
+        grpc_listen_port = 0;
+      };
+      clients = [{
+        url = "http://ildkule.pvv.ntnu.no:3100/loki/api/v1/push";
+      }];
+      scrape_configs = [{
+        job_name = "systemd-journal";
+        journal = {
+          max_age = "12h";
+          labels = {
+            job = "systemd-journal";
+            host = config.networking.hostName;
+          };
+        };
+        relabel_configs = [
+          {
+            source_labels = [ "__journal__systemd_unit" ];
+            target_label = "unit";
+          }
+          {
+            source_labels = [ "__journal_priority_keyword" ];
+            target_label = "level";
+          }
+        ];
+      }];
+    };
+  };
+}

docs/development-misc.md

@@ -0,0 +1,103 @@
+# Miscellaneous development notes
+
+This document contains a bunch of information that is not particularly specific to the pvv nixos config,
+but concerns technologies we use often or gotchas to be aware of when working with NixOS. A lot of the information
+here is already public information spread around the internet, but we've collected some of the items we use often
+here.
+
+## The firewall
+
+`networking.firewall` is a NixOS module that configures `iptables` rules on the machine. It is enabled by default on
+all of our machines, and it can be easy to forget about it when setting up new services, especially when we are the
+ones creating the NixOS module.
+
+When setting up a new service that listens on a TCP or UDP port, make sure to add the appropriate ports to either
+`networking.firewall.allowedTCPPorts` or `networking.firewall.allowedUDPPorts`.
+
+You can list out the current firewall rules by running `sudo iptables -L -n -v` on the machine.
+
+## Finding stuff
+
+Finding stuff, both underlying implementation and usage is absolutely crucial when working on nix.
+Oftentimes, the documentation will be outdated, lacking or just plain out wrong. These are some of
+the techniques we have found to be quite good when working with nix.
+
+### [ripgrep](https://github.com/BurntSushi/ripgrep)
+
+ripgrep (or `rg` for short) is a tool that lets you recursively grep for regex patters in a directory.
+
+It is great for finding references to configuration, and where and how certain things are used. It is
+especially great when working with [nixpkgs](https://github.com/NixOS/nixpkgs), which is quite large.
+
+### GitHub Search
+
+When trying to set up a new service or reconfigure something, it is very common that someone has done it
+before you, but it has never been documented anywhere. A lot of Nix code exists on GitHub, and you can
+easily query it by using the `lang:nix` filter in the search bar.
+
+For example: https://github.com/search?q=lang%3Anix+dibbler&type=code
+
+## rsync
+
+`rsync` is a tool for synchronizing files between machines. It is very useful when transferring large
+amounts of data from a to b. We use it for multiple things, often when data is produced or stored on
+one machine, and we want to process or convert it on another. For example, we use it to transfer gitea
+artifacts, to transfer gallery pictures, to transfer minecraft world data for map rendering, and more.
+
+Along with `rsync`, we often use a lesser known tool called `rrsync`, which you can use inside an ssh
+configuration (`authorized_keys` file) to restrict what paths a user can access when connecting over ssh.
+This is useful both as a security measure, but also to avoid accidental overwrites of files outside the intended
+path. `rrsync` will use chroot to restrict what paths the user can access, as well as refuse to run arbitrary commands.
+
+## `nix repl`
+
+`nix repl` is an interactive REPL for the Nix language. It is very useful for experimenting with Nix code,
+and testing out small snippets of code to make sure it behaves as expected. You can also use it to explore
+NixOS machine configurations, to interactively see that the configuration evaluates to what you expect.
+
+```
+# While in the pvv-nixos-config directory
+nix repl .
+
+# Upon writing out the config path and clickin [Tab], you will get autocompletion suggestions:
+nix-repl> nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts._
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.bekkalokk.pvv.ntnu.no-nixos-metrics
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.idp.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.minecraft.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.pvv.org
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.pw.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.roundcubeplaceholder.example.com
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.snappymail.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.webmail.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.wiki.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.www.pvv.ntnu.no
+nixosConfigurations.bekkalokk.config.services.nginx.virtualHosts.www.pvv.org
+```
+
+## `nix why-depends`
+
+If you ever wonder why a certain package is being used as a dependency of another package,
+or another machine, you can use `nix why-depends` to find the dependency path from one package to another.
+This is often useful after updating nixpkgs and finding an error saying that a certain package is insecure,
+broken or whatnot. You can do something like the following
+
+```bash
+# Why does bekkalokk depend on openssl?
+nix why-depends .#nixosConfigurations.bekkalokk.config.system.build.toplevel .#nixosConfigurations.bekkalokk.pkgs.openssl
+
+# Why does bekkalokk's minecraft-server depend on zlib? (this is not real)
+nix why-depends .#nixosConfigurations.bekkalokk.pkgs.minecraft-server .#nixosConfigurations.bekkalokk.pkgs.zlib
+```
+
+## php-fpm
+
+php-fpm (FastCGI Process Manager) is a PHP implementation that is designed for speed and production use. We host a bunch
+of different PHP applications (including our own website), and so we use php-fpm quite a bit. php-fpm typically exposes a
+unix socket that nginx will connect to, and php-fpm will then render php upon web requests forwarded from nginx and return
+it.
+
+php-fpm has a tendency to be a bit hard to debug. It is not always very willing to spit out error messages and logs, and so
+it can be a bit hard to figure out what's up when something goes wrong. You should see some of the commented stuff laying around
+in the website code on bekkalokk for examples of how to configure php-fpm for better logging and error reporting.

docs/development.md

@@ -0,0 +1,190 @@
+# Development - working on the PVV machines
+
+This document outlines the process of editing our NixOS configurations, and testing and deploying said changes
+to the machines. Most of the information written here is specific to the PVV NixOS configuration, and the topics
+will not really cover the nix code itself in detail. You can find some more resources for that by either following
+the links from the *Upstream documentation* section below, or in [Miscellaneous development notes](./development-misc.md).
+
+## Editing nix files
+
+> [!WARN]
+> Before editing any nix files, make sure to read [Secret management and `sops-nix`](./secret-management.md)!
+> We do not want to add any secrets in plaintext to the nix files, and certainly not commit and publish
+> them into the common public.
+
+The files are plaintext code, written in the [`Nix` language](https://nix.dev/manual/nix/stable/language/).
+
+Below is a list of important files and directories, and a description of what they contain.
+
+### `flake.nix`
+
+The `flake.nix` file is a [nix flake](https://wiki.nixos.org/wiki/Flakes) and makes up the entrypoint of the
+entire configuration. It declares what inputs are used (similar to dependencies), as well as what outputs the
+flake exposes. In our case, the most important outputs are the `nixosConfigurations` (our machine configs), but
+we also expose custom modules, packages, devshells, and more. You can run `nix flake show` to get an overview of
+the outputs (however you will need to [enable the `nix-flakes` experimental option](https://wiki.nixos.org/wiki/Flakes#Setup)).
+
+You will find that a lot of the flake inputs are the different PVV projects that we develop, imported to be hosted
+on the NixOS machines. This makes it easy to deploy changes to these projects, as we can just update the flake input
+to point to a new commit or version, and then rebuild the machines.
+
+A NixOS configuration is usually made with the `nixpkgs.lib.nixosSystem` function, however we have a few custom wrapper
+functions named `nixosConfig` and `stableNixosConfig` that abstracts away some common configuration we want on all our machines.
+
+### `values.nix`
+
+`values.nix` is a somewhat rare pattern in NixOS configurations around the internet. It contains a bunch of constant values
+that we use throughout the configuration, such as IP addresses, DNS names, paths and more. This not only makes it easier to
+change the values should we need to, but it also makes the configuration more readable. Instead of caring what exact IP any
+machine has, you can write `values.machines.name.ipv4` and abstract the details away.
+
+### `base`
+
+The `base` directory contains a bunch of NixOS configuration that is common for all or most machines. Some of the config
+you will find here sets defaults for certain services without enabling them, so that when they are enabled in a machine config,
+we don't need to repeat the same defaults over again. Other parts actually enable certain services that we want on all machines,
+such as `openssh` or the auto upgrade timer.
+
+### Vendoring `modules` and `packages`
+
+Sometimes, we either find that the packages or modules provided by `nixpkgs` is not sufficient for us,
+or that they are bugged in some way that can not be easily overrided. There are also cases where the
+modules or packages does not exist. In these cases, we tend to either copy and modify the modules and
+packages from nixpkgs, or create our own. These modules and packages end up in the top-level `modules`
+and `packages` directories. They are usually exposed in `flake.nix` as flake outputs `nixosModules.<name>`
+and `packages.<platform>.<name>`, and they are usually also added to the machines that need them in the flake.
+
+In order to override or add an extra package, the easiest way is to use an [`overlay`](https://wiki.nixos.org/wiki/Overlays).
+This makes it so that the package from `pkgs.<name>` now refers to the modified variant of the package.
+
+In order to add a module, you can just register it in the modules of the nixos machine.
+In order to override a module, you also have to use `disabledModules = [ "<path-relative-to-nixpkgs/modules>" ];`.
+Use `rg` to find examples of the latter.
+
+Do note that if you believe a new module to be of high enough quality, or the change you are making to be
+relevant for every nix user, you should strongly consider also creating a PR towards nixpkgs. However,
+getting changes made there has a bit higher threshold and takes more time than making changes in the PVV config,
+so feel free to make the changes here first. We can always remove the changes again once the upstreaming is finished.
+
+### `users`, `secrets` and `keys`
+
+For `users`, see [User management](./users.md)
+
+For `secrets` and `keys`, see [Secret management and `sops-nix`](./secret-management.md)
+
+### Collaboration
+
+We use our gitea to collaborate on changes to the nix configuration. Every PVV maintenance member should have
+access to the repository. The usual workflow is that we create a branch for the change we want to make, do a bunch
+of commits and changes, and then open a merge request for review (or just rebase on master if you know what you are doing).
+
+### Upstream documentation
+
+Here are different sources of documentation and stuff that you might find useful while
+writing, editing and debugging nix code.
+
+ - [nixpkgs repository](https://github.com/NixOS/nixpkgs)
+
+This is particularly useful to read the source code, as well as upstreaming pieces of code that we think
+everyone would want
+
+ - [NixOS search](https://search.nixos.org/)
+
+This is useful for searching for both packages and NixOS options.
+
+ - [nixpkgs documentation](https://nixos.org/manual/nixpkgs/stable/)
+ - [NixOS documentation](https://nixos.org/manual/nixos/stable/)
+ - [nix (the tool) documentation](https://nix.dev/manual/nix/stable/)
+
+All of the three above make up the official documentation with all technical
+details about the different pieces that makes up NixOS.
+
+ - [The official NixOS wiki](https://wiki.nixos.org)
+
+User-contributed guides, tips and tricks, and whatever else.
+
+ - [nix.dev](https://nix.dev)
+
+Additional stuff
+
+ - [Noogle](https://noogle.dev)
+
+This is useful when looking for nix functions and packaging helpers.
+
+## Testing and deploying changes
+
+After editing the nix files on a certain branch, you will want to test and deploy the changes to the machines.
+Unfortunately, we don't really have a good setup for testing for runtime correctness locally, but we can at least
+make sure that the code evaluates and builds correctly before deploying.
+
+To just check that the code evaluates without errors, you can run:
+
+```bash
+nix flake check
+# Or if you want to keep getting all errors before it quits:
+nix flake check --keep-going
+```
+
+> [!NOTE]
+> If you are making changes that involves creating new nix files, remember to `git add` those files before running
+> any nix commands. Nix refuses to acknowledge files that are not either commited or at least staged. It will spit
+> out an error message about not finding the file in question.
+
+### Building machine configurations
+
+To build any specific machine configuration and look at the output, you can run:
+
+```bash
+nix build .#nixosConfigurations.<machine-name>.config.system.build.toplevel
+# or just
+nix build .#<machine-name>
+```
+
+This will create a symlink name `./result` to a directory containing the built NixOS system. It is oftentimes
+the case that config files for certain services only end up in the nix store without being put into `/etc`. If you wish
+to read those files, you can often find them by looking at the systemd unit files in `./result/etc/systemd/system/`.
+(if you are using vim, `gf` or go-to-file while the cursor is over a file path is a useful trick while doing this).
+
+If you have edited something that affects multiple machines, you can also build all important machines at once by running:
+
+```bash
+nix build .#
+```
+
+> [!NOTE]
+> Building all machines at once can take a long time, depending on what has changed and whether you have already
+> built some of the machines recently. Be prepared to wait for up to an hour to build all machines from scratch
+> if this is the first time.
+
+### Deploying to machines
+
+> [!WARN]
+> Be careful to think about state when testing changes against the machines. Sometimes, a certain change
+> can lead to irreversible changes to the data stored on the machine. An example would be a set of database
+> migrations applied when testing a newer version of a service. Unless that service also comes with downwards
+> migrations, you can not go back to the previous version without losing data.
+
+To deploy the changes to a machine, you should first SSH into the machine, and clone the pvv-nixos-config
+repository unless you have already done so. After that, checkout the branch you want to deploy from, and rebuild:
+
+```bash
+# Run this while in the pvv-nixos-config directory
+sudo nixos-rebuild switch --update-input nixpkgs --update-input nixpkgs-unstable --no-write-lock-file --refresh --flake .# --upgrade
+```
+
+This will rebuild the NixOS system on the current branch and switch the system configuration to reflect the new changes.
+
+Note that unless you eventually merge the current changes into `main`, the machine will rebuild itself automatically and
+revert the changes on the next nightly rebuild (tends to happen when everybody is asleep).
+
+### Forcefully reset to `main`
+
+If you ever want to reset a machine to the `main` branch, you can do so by running:
+
+```bash
+nixos-rebuild switch --update-input nixpkgs --update-input nixpkgs-unstable --no-write-lock-file --refresh --upgrade --flake git+https://git.pvv.ntnu.no/Drift/pvv-nixos-config.git
+```
+
+This will ignore the current branch and just pull the latest `main` from the git repository directly from gitea.
+You can also use this command if there are updates on the `main` branch that you want to deploy to the machine without
+waiting for the nightly rebuild.

docs/secret-management.md

@@ -0,0 +1,160 @@
+# Secret management and `sops-nix`
+
+Nix config is love, nix config is life, and publishing said config to the
+internet is not only a good deed and kinda cool, but also encourages properly
+secured configuration as opposed to [security through obscurity](https://en.wikipedia.org/wiki/Security_through_obscurity).
+That being said, there are some details of the config that we really shouldn't
+share with the general public. In particular, there are so-called *secrets*, that is
+API keys, passwords, tokens, cookie secrets, salts, peppers and jalapenos that we'd
+rather keep to ourselves. However, it is not entirely trivial to do so in the NixOS config.
+For one, we'd have to keep these secrets out of the public git repo somehow, and secondly
+everything that is configured via nix ends up as world readable files (i.e. any user on the
+system can read the file) in `/nix/store`.
+
+In order to solve this, we use a NixOS module called [`sops-nix`](https://github.com/Mic92/sops-nix)
+which uses a technology called [`sops`](https://github.com/getsops/sops) behind the scenes.
+The idea is simple: we encrypt these secrets with a bunch of different keys and store the
+encrypted files in the git repo. First of all, we encrypt the secrets a bunch of time with
+PVV maintenance member's keys, so that we can decrypt and edit the contents. Secondly, we
+encrypt the secrets with the [host keys]() of the NixOS machines, so that they can decrypt
+the secrets. The secrets will be decrypted and stored in a well-known location (usually `/run/secrets`)
+so that they do not end up in the nix store, and are not world readable.
+
+This way, we can both keep the secrets in the git repository and let multiple people edit them,
+but also ensure that they don't end up in the wrong hands.
+
+## Adding a new machine
+
+In order to add a new machine to the nix-sops setup, you should do the following:
+
+```console
+# Create host keys (if they don't already exist)
+ssh-keygen -A -b 4096
+
+# Derive an age-key from the public host key
+nix-shell -p ssh-to-age --run 'cat /etc/ssh/ssh_host_ed25519_key.pub | ssh-to-age'
+
+# Register the age key in .sops.yaml
+vim .sops.yaml
+```
+
+The contents of `.sops.yaml` should look like this:
+
+```yaml
+keys:
+  # Users
+  ...
+
+  # Hosts
+  ...
+  - &host_<machine_name> <public_age_key>
+
+creation_rules:
+  ...
+
+  - path_regex: secrets/<machine_name>/[^/]+\.yaml$
+    key_groups:
+    - age:
+      - *host_<machine_name>
+      - ... user keys
+    - pgp:
+      - ... user keys
+```
+
+> [!NOTE]
+> Take care that all the keys in the `age` and `pgp` sections are prefixed
+> with a `-`, or else sops might try to encrypt the secrets in a way where
+> you need both keys present to decrypt the content. Also, it tends to throw
+> interesting errors when it fails to do so.
+
+```console
+# While cd-ed into the repository, run this to get a shell with the `sops` tool present
+nix-shell
+```
+
+Now you should also be able to edit secrets for this machine by running:
+
+```
+sops secrets/<machine_name>/<machine_name>.yaml
+```
+
+## Adding a user
+
+Adding a user is quite similar to adding a new machine.
+This guide assumes you have already set up SSH keys.
+
+```
+# Derive an age-key from your key
+# (edit the path to the key if it is named something else)
+nix-shell -p ssh-to-age --run 'cat ~/.ssh/id_ed25519.pub | ssh-to-age'
+
+# Register the age key in .sops.yaml
+vim .sops.yaml
+```
+
+The contents of `.sops.yaml` should look like this:
+
+```yaml
+keys:
+  # Users
+  ...
+  - &user_<user_name> <public_age_key>
+
+  # Hosts
+  ...
+
+creation_rules:
+  ...
+
+  # Do this for all the machines you are planning to edit
+  # (or just do it for all machines)
+  - path_regex: secrets/<machine_name>/[^/]+\.yaml$
+    key_groups:
+    - age:
+      - *host_<machine_name>
+      - ... user keys
+      - *host_<user_name>
+    - pgp:
+      - ... user keys
+```
+
+Now that sops is properly configured to recognize the key, you need someone
+who already has access to decrypt all the secrets and re-encrypt them with your
+key. At this point, you should probably [open a PR](https://docs.gitea.com/usage/issues-prs/pull-request)
+and ask someone in PVV maintenance if they can checkout the PR branch, run the following
+command and push the diff back into the PR (and maybe even ask them to merge if you're feeling
+particularly needy).
+
+```console
+sops updatekeys secrets/*/*.yaml
+```
+
+## Updating keys
+
+> [!NOTE]
+> At some point, we found this flag called `sops -r` that seemed to be described to do what
+> `sops updatekeys` does, do not be fooled. This only rotates the "inner key" for those who
+> already have the secrets encrypted with their key.
+
+Updating keys is done with this command:
+
+```console
+sops updatekeys secrets/*/*.yaml
+```
+
+However, there is a small catch. [oysteikt](https://git.pvv.ntnu.no/oysteikt) has kinda been
+getting gray hairs lately, and refuses to use modern technology - he is still stuck using GPG.
+This means that to be able to re-encrypt the sops secrets, you will need to have a gpg keychain
+with his latest public key available. The key has an expiry date, so if he forgets to update it,
+you should send him and angry email and tag him a bunch of times in a gitea issue. If the key
+is up to date, you can do the following:
+
+```console
+# Fetch gpg (unless you have it already)
+nix-shell -p gpg
+
+# Import oysteikts key to the gpg keychain
+gpg --import ./keys/oysteikt.pub
+```
+
+Now you should be able to run the `sops updatekeys` command again.

docs/users.md

@@ -0,0 +1,50 @@
+# User management
+
+Due to some complications with how NixOS creates users compared to how we used to
+create users with the salt-based setup, the NixOS machine users are created and
+managed separately. We tend to create users on-demand, whenever someone in PVV
+maintenance want to work on the NixOS machines.
+
+## Setting up a new user
+
+You can find the files for the existing users, and thereby examples of user files
+in the [`users`](../users) directory. When creating a new file here, you should name it
+`your-username.nix`, and add *at least* the following contents:
+
+```nix
+{ pkgs, ... }:
+{
+  users.users."<username>" = {
+    isNormalUser = true;
+    extraGroups = [
+      "wheel" # In case you wanna use sudo (you probably do)
+      "nix-builder-users" # Arbitrary access to write to the nix store
+    ];
+
+    # Any packages you frequently use to manage servers go here.
+    # Please don't pull gigantonormous packages here unless you
+    # absolutely need them, and remember that any package can be
+    # pulled via nix-shell if you only use it once in a blue moon.
+    packages = with pkgs; [
+      bottom
+      eza
+    ];
+
+    # Not strictly needed, but we recommend adding your public SSH
+    # key here. If it is not present, you will have to log into the
+    # machine as 'root' before setting your password for every NixOS
+    # machine you have not logged into yet.
+    openssh.authorizedKeys.keys = [
+      "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIjiQ0wg4lpC7YBMAAHoGmgwqHOBi+EUz5mmCymGlIyT my-key"
+    ];
+  };
+}
+```
+
+The file will be picked up automatically, so creating the file and adding the
+contents should be enough to get you registered. You should
+[open a PR](https://docs.gitea.com/usage/issues-prs/pull-request) with the new
+code so the machines will be rebuilt with your user present.
+
+See also [Secret Management](./secret-management.md) for how to add your keys to the
+system that lets us add secrets (API keys, password, etc.) to the NixOS config.

flake.lock

@@ -1,5 +1,26 @@
 {
   "nodes": {
+    "devshell": {
+      "inputs": {
+        "nixpkgs": [
+          "nix-topology",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1728330715,
+        "narHash": "sha256-xRJ2nPOXb//u1jaBnDP56M7v5ldavjbtR6lfGqSvcKg=",
+        "owner": "numtide",
+        "repo": "devshell",
+        "rev": "dd6b80932022cea34a019e2bb32f6fa9e494dfef",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "devshell",
+        "type": "github"
+      }
+    },
     "disko": {
       "inputs": {
         "nixpkgs": [
@@ -7,19 +28,54 @@
         ]
       },
       "locked": {
-        "lastModified": 1764627417,
+        "lastModified": 1736864502,
-        "narHash": "sha256-D6xc3Rl8Ab6wucJWdvjNsGYGSxNjQHzRc2EZ6eeQ6l4=",
+        "narHash": "sha256-ItkIZyebGvNH2dK9jVGzJHGPtb6BSWLN8Gmef16NeY0=",
         "owner": "nix-community",
         "repo": "disko",
-        "rev": "5a88a6eceb8fd732b983e72b732f6f4b8269bef3",
+        "rev": "0141aabed359f063de7413f80d906e1d98c0c123",
         "type": "github"
       },
       "original": {
         "owner": "nix-community",
+        "ref": "v1.11.0",
         "repo": "disko",
         "type": "github"
       }
     },
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1696426674,
+        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1726560853,
+        "narHash": "sha256-X6rJYSESBVr3hBoH0WbKE5KvhPU5bloyZ2L4K60/fPQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c1dfcf08411b08f6b8615f7d8971a2bfa81d5e8a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "gergle": {
       "inputs": {
         "nixpkgs": [
@@ -29,17 +85,40 @@
       "locked": {
         "lastModified": 1764868579,
         "narHash": "sha256-rfTUOIc0wnC4+19gLVfPbHfXx/ilfuUix6bWY+yaM2U=",
-        "ref": "refs/heads/main",
+        "ref": "main",
         "rev": "9c923d1d50daa6a3b28c3214ad2300bfaf6c8fcd",
         "revCount": 22,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Grzegorz/gergle.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Grzegorz/gergle.git"
       }
     },
+    "gitignore": {
+      "inputs": {
+        "nixpkgs": [
+          "nix-topology",
+          "pre-commit-hooks",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1709087332,
+        "narHash": "sha256-HG2cCnktfHsKV0s4XW83gU3F57gaTljL9KNSuG6bnQs=",
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "rev": "637db329424fd7e46cf4185293b9cc8c88c95394",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "gitignore.nix",
+        "type": "github"
+      }
+    },
     "greg-ng": {
       "inputs": {
         "nixpkgs": [
@@ -48,15 +127,16 @@
         "rust-overlay": "rust-overlay"
       },
       "locked": {
-        "lastModified": 1764868843,
+        "lastModified": 1765760377,
-        "narHash": "sha256-ZXYLXKO+VjAJr2f5zz+7SuKFICfI2eZnmTgS/626YE0=",
+        "narHash": "sha256-2+lgzUjVas9hPSeWn52MwuX+iidMN4RkzkHo4vrGmR8=",
-        "ref": "refs/heads/main",
+        "ref": "main",
-        "rev": "c095533c50e80dd18ac48046f1479cf4d83c631c",
+        "rev": "f340dc5b9c9f3b75b7aca41f56f8869b9e28cf8c",
-        "revCount": 52,
+        "revCount": 58,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Grzegorz/greg-ng.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Grzegorz/greg-ng.git"
       }
@@ -70,13 +150,14 @@
       "locked": {
         "lastModified": 1764867811,
         "narHash": "sha256-UWHiwr8tIcGcVxMLvAdNxDbQ8QuHf3REHboyxvFkYEI=",
-        "ref": "refs/heads/master",
+        "ref": "master",
         "rev": "c9983e947efe047ea9d6f97157a1f90e49d0eab3",
         "revCount": 81,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Grzegorz/grzegorz-clients.git"
       },
       "original": {
+        "ref": "master",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Grzegorz/grzegorz-clients.git"
       }
@@ -106,18 +187,20 @@
       "inputs": {
         "nixpkgs": [
           "nixpkgs"
-        ]
+        ],
+        "rust-overlay": "rust-overlay_2"
       },
       "locked": {
-        "lastModified": 1756124334,
+        "lastModified": 1766407405,
-        "narHash": "sha256-DXFmSpgI8FrqcdqY7wg5l/lpssWjslHq5ufvyp/5k4o=",
+        "narHash": "sha256-UEJ8F8/oG70biWRrGbL5/aB7OXzzvnYs+jxkR07UHvA=",
-        "ref": "refs/heads/main",
+        "ref": "main",
-        "rev": "83760b1ebcd9722ddf58a4117d29555da65538ad",
+        "rev": "e719840f72ca1b0cd169562a3a0de69899821de0",
-        "revCount": 13,
+        "revCount": 16,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/minecraft-heatmap.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/minecraft-heatmap.git"
       }
@@ -129,15 +212,16 @@
         ]
       },
       "locked": {
-        "lastModified": 1765903589,
+        "lastModified": 1765904683,
-        "narHash": "sha256-JRLmckeM4G2hkH2V3VdfjHrrsWgJ8j7rZDYYjHTkRqA=",
+        "narHash": "sha256-uXM56y5n5GWpCiCNdKlTcCAy2IntgDB21c4gBDU30io=",
-        "ref": "refs/heads/main",
+        "ref": "main",
-        "rev": "7c86d342e68506fcd83cb74af3336f99ff522a0a",
+        "rev": "6fae27b1659efb6774cf08a4e36ed29ab0e24105",
-        "revCount": 24,
+        "revCount": 26,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/minecraft-kartverket.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/minecraft-kartverket.git"
       }
@@ -151,17 +235,42 @@
       "locked": {
         "lastModified": 1743881366,
         "narHash": "sha256-ScGA2IHPk9ugf9bqEZnp+YB/OJgrkZblnG/XLEKvJAo=",
-        "ref": "refs/heads/main",
+        "ref": "main",
         "rev": "db2e4becf1b11e5dfd33de12a90a7d089fcf68ec",
         "revCount": 11,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Drift/nix-gitea-themes.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Drift/nix-gitea-themes.git"
       }
     },
+    "nix-topology": {
+      "inputs": {
+        "devshell": "devshell",
+        "flake-utils": "flake-utils",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "pre-commit-hooks": "pre-commit-hooks"
+      },
+      "locked": {
+        "lastModified": 1765969653,
+        "narHash": "sha256-qVpQxyvdByeDfb+d+jhbyNna2Ie+w85iHpt4Qu0rv/E=",
+        "owner": "oddlama",
+        "repo": "nix-topology",
+        "rev": "0ed73e5a1b65eb8ed388d070ebe8dedb9182f466",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oddlama",
+        "ref": "main",
+        "repo": "nix-topology",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1764806471,
@@ -188,6 +297,33 @@
         "url": "https://nixos.org/channels/nixos-unstable-small/nixexprs.tar.xz"
       }
     },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-compat": "flake-compat",
+        "gitignore": "gitignore",
+        "nixpkgs": [
+          "nix-topology",
+          "nixpkgs"
+        ],
+        "nixpkgs-stable": [
+          "nix-topology",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1730797577,
+        "narHash": "sha256-SrID5yVpyUfknUTGWgYkTyvdr9J1LxUym4om3SVGPkg=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "1864030ed24a2b8b4e4d386a5eeaf0c5369e50a9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
     "pvv-calendar-bot": {
       "inputs": {
         "nixpkgs": [
@@ -197,13 +333,14 @@
       "locked": {
         "lastModified": 1764869785,
         "narHash": "sha256-FGTIpC7gB4lbeL0bfYzn1Ge0PaCpd7VqWBLhJBx0i4A=",
-        "ref": "refs/heads/main",
+        "ref": "main",
         "rev": "8ce7fb0b1918bdb3d1489a40d73895693955e8b2",
         "revCount": 23,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/calendar-bot.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/calendar-bot.git"
       }
@@ -215,15 +352,16 @@
         ]
       },
       "locked": {
-        "lastModified": 1757332682,
+        "lastModified": 1765978548,
-        "narHash": "sha256-4p4aVQWs7jHu3xb6TJlGik20lqbUU/Fc0/EHpzoRlO0=",
+        "narHash": "sha256-VDSPpw+/Mgo+JujoW12CRlkTs9o0tX/FEL2AR5kl5+Q=",
-        "ref": "refs/heads/main",
+        "ref": "main",
-        "rev": "da1113341ad9881d8d333d1e29790317bd7701e7",
+        "rev": "961f021d27f86b2aedd16290dbf85bdd9d50fd42",
-        "revCount": 518,
+        "revCount": 532,
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/nettsiden.git"
       },
       "original": {
+        "ref": "main",
         "type": "git",
         "url": "https://git.pvv.ntnu.no/Projects/nettsiden.git"
       }
@@ -238,6 +376,7 @@
         "minecraft-heatmap": "minecraft-heatmap",
         "minecraft-kartverket": "minecraft-kartverket",
         "nix-gitea-themes": "nix-gitea-themes",
+        "nix-topology": "nix-topology",
         "nixpkgs": "nixpkgs",
         "nixpkgs-unstable": "nixpkgs-unstable",
         "pvv-calendar-bot": "pvv-calendar-bot",
@@ -253,11 +392,32 @@
         ]
       },
       "locked": {
-        "lastModified": 1764816035,
+        "lastModified": 1765680428,
-        "narHash": "sha256-F0IQSmSj4t2ThkbWZooAhkCTO+YpZSd2Pqiv2uoYEHo=",
+        "narHash": "sha256-fyPmRof9SZeI14ChPk5rVPOm7ISiiGkwGCunkhM+eUg=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "74d9abb7c5c030469f90d97a67d127cc5d76c238",
+        "rev": "eb3898d8ef143d4bf0f7f2229105fc51c7731b2f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    },
+    "rust-overlay_2": {
+      "inputs": {
+        "nixpkgs": [
+          "minecraft-heatmap",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1766371695,
+        "narHash": "sha256-W7CX9vy7H2Jj3E8NI4djHyF8iHSxKpb2c/7uNQ/vGFU=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "d81285ba8199b00dc31847258cae3c655b605e8c",
         "type": "github"
       },
       "original": {
@@ -273,18 +433,34 @@
         ]
       },
       "locked": {
-        "lastModified": 1764483358,
+        "lastModified": 1766894905,
-        "narHash": "sha256-EyyvCzXoHrbL467YSsQBTWWg4sR96MH1sPpKoSOelB4=",
+        "narHash": "sha256-pn8AxxfajqyR/Dmr1wnZYdUXHgM3u6z9x0Z1Ijmz2UQ=",
         "owner": "Mic92",
         "repo": "sops-nix",
-        "rev": "5aca6ff67264321d47856a2ed183729271107c9c",
+        "rev": "61b39c7b657081c2adc91b75dd3ad8a91d6f07a7",
         "type": "github"
       },
       "original": {
         "owner": "Mic92",
+        "ref": "master",
         "repo": "sops-nix",
         "type": "github"
       }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
     }
   },
   "root": "root",

flake.nix

@@ -5,35 +5,38 @@
     nixpkgs.url = "https://nixos.org/channels/nixos-25.11-small/nixexprs.tar.xz";
     nixpkgs-unstable.url = "https://nixos.org/channels/nixos-unstable-small/nixexprs.tar.xz";
 
-    sops-nix.url = "github:Mic92/sops-nix";
+    sops-nix.url = "github:Mic92/sops-nix/master";
     sops-nix.inputs.nixpkgs.follows = "nixpkgs";
 
-    disko.url = "github:nix-community/disko";
+    disko.url = "github:nix-community/disko/v1.11.0";
     disko.inputs.nixpkgs.follows = "nixpkgs";
 
-    pvv-nettsiden.url = "git+https://git.pvv.ntnu.no/Projects/nettsiden.git";
+    nix-topology.url = "github:oddlama/nix-topology/main";
+    nix-topology.inputs.nixpkgs.follows = "nixpkgs";
+
+    pvv-nettsiden.url = "git+https://git.pvv.ntnu.no/Projects/nettsiden.git?ref=main";
     pvv-nettsiden.inputs.nixpkgs.follows = "nixpkgs";
 
-    pvv-calendar-bot.url = "git+https://git.pvv.ntnu.no/Projects/calendar-bot.git";
+    pvv-calendar-bot.url = "git+https://git.pvv.ntnu.no/Projects/calendar-bot.git?ref=main";
     pvv-calendar-bot.inputs.nixpkgs.follows = "nixpkgs";
 
     matrix-next.url = "github:dali99/nixos-matrix-modules/v0.8.0";
     matrix-next.inputs.nixpkgs.follows = "nixpkgs";
 
-    nix-gitea-themes.url = "git+https://git.pvv.ntnu.no/Drift/nix-gitea-themes.git";
+    nix-gitea-themes.url = "git+https://git.pvv.ntnu.no/Drift/nix-gitea-themes.git?ref=main";
     nix-gitea-themes.inputs.nixpkgs.follows = "nixpkgs";
 
-    minecraft-heatmap.url = "git+https://git.pvv.ntnu.no/Projects/minecraft-heatmap.git";
+    minecraft-heatmap.url = "git+https://git.pvv.ntnu.no/Projects/minecraft-heatmap.git?ref=main";
     minecraft-heatmap.inputs.nixpkgs.follows = "nixpkgs";
 
-    greg-ng.url = "git+https://git.pvv.ntnu.no/Grzegorz/greg-ng.git";
+    greg-ng.url = "git+https://git.pvv.ntnu.no/Grzegorz/greg-ng.git?ref=main";
     greg-ng.inputs.nixpkgs.follows = "nixpkgs";
-    gergle.url = "git+https://git.pvv.ntnu.no/Grzegorz/gergle.git";
+    gergle.url = "git+https://git.pvv.ntnu.no/Grzegorz/gergle.git?ref=main";
     gergle.inputs.nixpkgs.follows = "nixpkgs";
-    grzegorz-clients.url = "git+https://git.pvv.ntnu.no/Grzegorz/grzegorz-clients.git";
+    grzegorz-clients.url = "git+https://git.pvv.ntnu.no/Grzegorz/grzegorz-clients.git?ref=master";
     grzegorz-clients.inputs.nixpkgs.follows = "nixpkgs";
 
-    minecraft-kartverket.url = "git+https://git.pvv.ntnu.no/Projects/minecraft-kartverket.git";
+    minecraft-kartverket.url = "git+https://git.pvv.ntnu.no/Projects/minecraft-kartverket.git?ref=main";
     minecraft-kartverket.inputs.nixpkgs.follows = "nixpkgs";
   };
 
@@ -57,6 +60,16 @@
   in {
     inputs = lib.mapAttrs (_: src: src.outPath) inputs;
 
+    pkgs = forAllSystems (system:
+      import nixpkgs {
+        inherit system;
+        config.allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg)
+          [
+            "nvidia-x11"
+            "nvidia-settings"
+          ];
+      });
+
     nixosConfigurations = let
       unstablePkgs = nixpkgs-unstable.legacyPackages.x86_64-linux;
 
@@ -230,14 +243,50 @@
         bluemap = pkgs.callPackage ./packages/bluemap.nix { };
 
         out-of-your-element = pkgs.callPackage ./packages/out-of-your-element.nix { };
-      } //
+      }
+      //
+      # Mediawiki extensions
       (lib.pipe null [
         (_: pkgs.callPackage ./packages/mediawiki-extensions { })
         (lib.flip builtins.removeAttrs ["override" "overrideDerivation"])
         (lib.mapAttrs' (name: lib.nameValuePair "mediawiki-${name}"))
       ])
-      // lib.genAttrs allMachines
+      //
-        (machine: self.nixosConfigurations.${machine}.config.system.build.toplevel);
+      # Machines
+      lib.genAttrs allMachines
+        (machine: self.nixosConfigurations.${machine}.config.system.build.toplevel)
+      //
+      # Nix-topology
+      (let
+        topology' = import inputs.nix-topology {
+          pkgs = import nixpkgs {
+            system = "x86_64-linux";
+            overlays = [ inputs.nix-topology.overlays.default ];
+          };
+
+          modules = [
+            ./topology
+            {
+              nixosConfigurations = lib.mapAttrs (_name: nixosCfg: nixosCfg.extendModules {
+                modules = [
+                  inputs.nix-topology.nixosModules.default
+                  ./topology/service-extractors/greg-ng.nix
+                ];
+              }) self.nixosConfigurations;
+            }
+          ];
+        };
+      in {
+        topology = topology'.config.output;
+        topology-png = pkgs.runCommand "pvv-config-topology-png" {
+          nativeBuildInputs = [ pkgs.writableTmpDirAsHomeHook ];
+        } ''
+          mkdir -p "$out"
+          for file in '${topology'.config.output}'/*.svg; do
+            ${lib.getExe pkgs.imagemagick} -density 300 -background none "$file" "$out"/"$(basename "''${file%.svg}.png")"
+          done
+        '';
+      });
     };
   };
 }

hosts/bakke/configuration.nix

@@ -3,7 +3,6 @@
   imports = [
       ./hardware-configuration.nix
       ../../base
-      ../../misc/metrics-exporters.nix
       ./filesystems.nix
     ];
 

hosts/bekkalokk/configuration.nix

@@ -4,7 +4,6 @@
     ./hardware-configuration.nix
 
     (fp /base)
-    (fp /misc/metrics-exporters.nix)
 
     ./services/bluemap.nix
     ./services/idp-simplesamlphp

hosts/bicep/configuration.nix

@@ -4,7 +4,6 @@
     ./hardware-configuration.nix
 
     (fp /base)
-    (fp /misc/metrics-exporters.nix)
     ./services/nginx
 
     ./services/calendar-bot.nix

hosts/brzeczyszczykiewicz/configuration.nix

@@ -4,7 +4,6 @@
       # Include the results of the hardware scan.
       ./hardware-configuration.nix
       (fp /base)
-      (fp /misc/metrics-exporters.nix)
 
       ./services/grzegorz.nix
     ];

hosts/georg/configuration.nix

@@ -4,7 +4,6 @@
       # Include the results of the hardware scan.
       ./hardware-configuration.nix
       (fp /base)
-      (fp /misc/metrics-exporters.nix)
 
       (fp /modules/grzegorz.nix)
     ];

hosts/ildkule/configuration.nix

@@ -4,7 +4,6 @@
       # Include the results of the hardware scan.
       ./hardware-configuration.nix
       (fp /base)
-      (fp /misc/metrics-exporters.nix)
 
       ./services/monitoring
       ./services/nginx

hosts/kommode/configuration.nix

@@ -4,7 +4,6 @@
     # Include the results of the hardware scan.
     ./hardware-configuration.nix
     (fp /base)
-    (fp /misc/metrics-exporters.nix)
 
     ./services/gitea
     ./services/nginx.nix
@@ -31,4 +30,3 @@
 
   system.stateVersion = "24.11";
 }
-

hosts/lupine/configuration.nix

@@ -4,7 +4,6 @@
     ./hardware-configuration/${lupineName}.nix
 
     (fp /base)
-    (fp /misc/metrics-exporters.nix)
 
     ./services/gitea-runner.nix
   ];

hosts/shark/configuration.nix

@@ -4,7 +4,6 @@
       # Include the results of the hardware scan.
       ./hardware-configuration.nix
       (fp /base)
-      (fp /misc/metrics-exporters.nix)
     ];
 
   sops.defaultSopsFile = fp /secrets/shark/shark.yaml;

hosts/ustetind/configuration.nix

@@ -3,7 +3,6 @@
 {
   imports = [
     (fp /base)
-    (fp /misc/metrics-exporters.nix)
 
     ./services/gitea-runners.nix
   ];

hosts/wenche/configuration.nix

@@ -4,11 +4,16 @@
       # Include the results of the hardware scan.
       ./hardware-configuration.nix
       (fp /base)
-      (fp /misc/metrics-exporters.nix)
-
-      (fp /misc/builder.nix)
     ];
 
+  nix.settings.trusted-users = [ "@nix-builder-users" ];
+  nix.daemonCPUSchedPolicy = "batch";
+
+  boot.binfmt.emulatedSystems = [
+    "aarch64-linux"
+    "armv7l-linux"
+  ];
+
   sops.defaultSopsFile = fp /secrets/wenche/wenche.yaml;
   sops.age.sshKeyPaths = [ "/etc/ssh/ssh_host_ed25519_key" ];
   sops.age.keyFile = "/var/lib/sops-nix/key.txt";

misc/builder.nix

@@ -1,11 +0,0 @@
-{ ... }:
-
-{
-  nix.settings.trusted-users = [ "@nix-builder-users" ];
-  nix.daemonCPUSchedPolicy = "batch";
-
-  boot.binfmt.emulatedSystems = [
-    "aarch64-linux"
-    "armv7l-linux"
-  ];
-}

misc/metrics-exporters.nix

@@ -1,80 +0,0 @@
-{ config, pkgs, values, ... }:
-
-{
-  services.prometheus.exporters.node = {
-    enable = true;
-    port = 9100;
-    enabledCollectors = [ "systemd" ];
-  };
-
-  systemd.services.prometheus-node-exporter.serviceConfig = {
-    IPAddressDeny = "any";
-    IPAddressAllow = [
-      "127.0.0.1"
-      "::1"
-      values.hosts.ildkule.ipv4
-      values.hosts.ildkule.ipv6
-    ];
-  };
-
-
-  services.prometheus.exporters.systemd = {
-    enable = true;
-    port = 9101;
-    extraFlags = [
-      "--systemd.collector.enable-restart-count"
-      "--systemd.collector.enable-ip-accounting"
-    ];
-  };
-
-  systemd.services.prometheus-systemd-exporter.serviceConfig = {
-    IPAddressDeny = "any";
-    IPAddressAllow = [
-      "127.0.0.1"
-      "::1"
-      values.hosts.ildkule.ipv4
-      values.hosts.ildkule.ipv6
-    ];
-  };
-  
-
-  networking.firewall.allowedTCPPorts = [ 9100 9101 ];
-
-  services.promtail = {
-    enable = true;
-    configuration = {
-      server = {
-        http_listen_port = 28183;
-        grpc_listen_port = 0;
-      };
-      clients = [
-        {
-          url = "http://ildkule.pvv.ntnu.no:3100/loki/api/v1/push";
-        }
-      ];
-      scrape_configs = [
-        {
-          job_name = "systemd-journal";
-          journal = {
-            max_age = "12h";
-            labels = {
-              job = "systemd-journal";
-              host = config.networking.hostName;
-            };
-          };
-          relabel_configs = [
-            {
-              source_labels = [ "__journal__systemd_unit" ];
-              target_label = "unit";
-            }
-            {
-              source_labels = [ "__journal_priority_keyword" ];
-              target_label = "level";
-            }
-          ];
-        }
-      ];
-    };
-  };
-
-}

misc/rust-motd.nix

@@ -1,86 +0,0 @@
-{ pkgs, lib, config, ... }:
-{
-  environment = {
-    systemPackages = with pkgs; [
-      rust-motd
-      toilet
-    ];
-
-    loginShellInit = let
-      motd = "${pkgs.rust-motd}/bin/rust-motd /etc/${config.environment.etc.rustMotdConfig.target}";
-    in ''
-      # Assure stdout is a terminal, so headless programs won't be broken
-      if [ "x''${SSH_TTY}" != "x" ]; then
-        ${motd}
-      fi
-    '';
-
-    etc.rustMotdConfig = {
-      target = "rust-motd-config.toml";
-      source = let
-
-        cfg = {
-          global = {
-            progress_full_character = "=";
-            progress_empty_character = "=";
-            progress_prefix = "[";
-            progress_suffix = "]";
-            time_format = "%Y-%m-%d %H:%M:%S";
-          };
-
-          banner = {
-            color = "red";
-            command = "hostname | ${pkgs.toilet}/bin/toilet -f mono9";
-          };
-
-          service_status = {
-            Accounts = "accounts-daemon";
-            Cron = "cron";
-            Docker = "docker";
-            Matrix = "matrix-synapse";
-            sshd = "sshd";
-          };
-
-          uptime = {
-            prefix = "Uptime: ";
-          };
-
-          # Not relevant for server
-          # user_service_status = {
-          #   Gpg-agent = "gpg-agent";
-          # };
-
-          filesystems = let
-            inherit (lib.attrsets) attrNames listToAttrs nameValuePair;
-            inherit (lib.lists) imap1;
-            inherit (config) fileSystems;
-
-            imap1Attrs' = f: set:
-              listToAttrs (imap1 (i: attr: f i attr set.${attr}) (attrNames set));
-
-            getName = i: v: if (v.label != null) then v.label else "<? ${toString i}>";
-          in
-            imap1Attrs' (i: n: v: nameValuePair (getName i v) n) fileSystems;
-
-          memory = {
-            swap_pos = "beside"; # or "below" or "none"
-          };
-
-          last_login = let
-            inherit (lib.lists) imap1;
-            inherit (lib.attrsets) filterAttrs nameValuePair attrValues listToAttrs;
-            inherit (config.users) users;
-
-            normalUsers = filterAttrs (n: v: v.isNormalUser || n == "root") users;
-            userNPVs = imap1 (index: user: nameValuePair user.name index) (attrValues normalUsers);
-          in listToAttrs userNPVs;
-
-          last_run = {};
-        };
-
-        toml = pkgs.formats.toml {};
-
-      in toml.generate "rust-motd.toml" cfg;
-    };
-  };
-}

topology/default.nix

@@ -0,0 +1,168 @@
+{ lib, config, ... }:
+let
+  inherit
+    (config.lib.topology)
+    mkInternet
+    mkRouter
+    mkSwitch
+    mkDevice
+    mkConnection
+    mkConnectionRev;
+  values = import ../values.nix;
+in {
+  imports = [
+    ./non-nixos-machines.nix
+  ];
+
+  ### Networks
+
+  networks.pvv = {
+    name = "PVV Network";
+    cidrv4 = values.ipv4-space;
+    cidrv6 = values.ipv6-space;
+  };
+
+  networks.site-vpn = {
+    name = "OpenVPN Site to Site";
+    style = {
+      primaryColor = "#9dd68d";
+      secondaryColor = null;
+      pattern = "dashed";
+    };
+  };
+
+  networks.ntnu = {
+    name = "NTNU";
+    cidrv4 = values.ntnu.ipv4-space;
+    cidrv6 = values.ntnu.ipv6-space;
+  };
+
+  nodes.internet = mkInternet {
+    connections = mkConnection "ntnu" "wan1";
+  };
+
+  nodes.ntnu = mkRouter "NTNU" {
+    interfaceGroups = [ ["wan1"] ["eth1" "eth2" "eth3"] ];
+    connections.eth1 = mkConnection "ntnu-pvv-router" "wan1";
+    connections.eth2 = mkConnection "ntnu-veggen" "wan1";
+    connections.eth3 = mkConnection "stackit" "*";
+    interfaces.eth1.network = "ntnu";
+  };
+
+  ### Brus
+
+  nodes.ntnu-pvv-router = mkRouter "NTNU PVV Gateway" {
+    interfaceGroups = [ ["wan1"] ["eth1"] ];
+    connections.eth1 = mkConnection "brus-switch" "eth1";
+    interfaces.eth1.network = "pvv";
+  };
+
+  nodes.brus-switch = mkSwitch "Brus Switch" {
+    interfaceGroups =  [ (lib.genList (i: "eth${toString i}") 16) ];
+
+    connections = let
+      connections' = [
+        (mkConnection "bekkalokk" "enp2s0")
+        # (mkConnection "bicep" "enp6s0f0")
+        (mkConnection "buskerud" "eth1")
+        (mkConnection "knutsen" "eth1")
+        (mkConnection "powerpuff-cluster" "eth1")
+        (mkConnection "lupine-1" "enp0s31f6")
+        (mkConnection "lupine-2" "enp0s31f6")
+        (mkConnection "lupine-3" "enp0s31f6")
+        (mkConnection "lupine-4" "enp0s31f6")
+        (mkConnection "lupine-5" "enp0s31f6")
+        (mkConnection "innovation" "em0")
+        (mkConnection "microbel" "eth0")
+        # (mkConnection "isvegg" "")
+        # (mkConnection "ameno" "")
+        # (mkConnection "sleipner" "")
+      ];
+    in builtins.listToAttrs (
+      lib.zipListsWith
+        (a: b: lib.nameValuePair a b)
+        (lib.genList (i: "eth${toString i}") 16)
+        connections'
+    );
+  };
+
+  nodes.knutsen = mkRouter "knutsen" {
+    interfaceGroups = [ ["eth1"] ["eth2"] ["vpn1"] ];
+    connections.eth2 = mkConnectionRev "brus-switch" "eth6";
+    # connections.vpn1 = mkConnection "ludvigsen" "vpn1";
+    interfaces.vpn1.network = "site-vpn";
+    interfaces.vpn1.virtual = true;
+  };
+
+  nodes.buskerud = mkDevice "buskerud" {
+    interfaceGroups = [ ["eth1"] ];
+  };
+
+  nodes.shark = {
+    guestType = "proxmox";
+    parent = config.nodes.buskerud.id;
+  };
+
+  ### Powerpuff
+
+  nodes.powerpuff-cluster = mkDevice "powerpuff-cluster" {
+    interfaceGroups = [ ["eth1"] ];
+  };
+
+  nodes.kommode = {
+    guestType = "proxmox";
+    parent = config.nodes.powerpuff-cluster.id;
+  };
+
+  nodes.bicep = {
+    guestType = "proxmox";
+    parent = config.nodes.powerpuff-cluster.id;
+  };
+
+  nodes.ustetind = {
+    guestType = "proxmox";
+    parent = config.nodes.powerpuff-cluster.id;
+  };
+
+  ### PVV
+
+  nodes.ntnu-veggen = mkRouter "NTNU-Veggen" {
+    interfaceGroups = [ ["wan1"] ["eth1"] ];
+    connections.eth1 = mkConnection "ludvigsen" "eth1";
+  };
+
+  nodes.ludvigsen = mkRouter "ludvigsen" {
+    interfaceGroups = [ ["eth1"] ["eth2"] ["vpn1"] ];
+    connections.eth2 = mkConnection "pvv-switch" "eth1";
+    interfaces.vpn1.network = "site-vpn";
+    interfaces.vpn1.virtual = true;
+    interfaces.eth1.network = "ntnu";
+    interfaces.eth2.network = "pvv";
+  };
+
+  nodes.pvv-switch = mkSwitch "PVV Switch (Terminalrommet)" {
+    interfaceGroups = [ ["eth1" "eth2" "eth3"] ];
+    connections.eth2 = mkConnection "brzeczyszczykiewicz" "eno1";
+    connections.eth3 = mkConnection "georg" "eno1";
+  };
+
+
+  ### Openstack
+
+  nodes.stackit = mkDevice "stackit" {
+    interfaceGroups = [ ["*"] ];
+  };
+
+  nodes.ildkule = {
+    guestType = "openstack";
+    parent = config.nodes.stackit.id;
+  };
+  nodes.wenche = {
+    guestType = "openstack";
+    parent = config.nodes.stackit.id;
+  };
+  nodes.bakke = {
+    guestType = "openstack";
+    parent = config.nodes.stackit.id;
+  };
+}

topology/non-nixos-machines.nix

@@ -0,0 +1,75 @@
+{ config, lib, ... }:
+let
+  inherit (config.lib.topology) mkDevice;
+in {
+  nodes.balduzius = mkDevice "balduzius" {
+    guestType = "proxmox";
+    parent = config.nodes.powerpuff-cluster.id;
+  };
+  nodes.tom = mkDevice "tom" {
+    guestType = "proxmox";
+    parent = config.nodes.powerpuff-cluster.id;
+  };
+  nodes.hildring = mkDevice "hildring" {
+    guestType = "proxmox";
+    parent = config.nodes.powerpuff-cluster.id;
+  };
+  nodes.microbel = mkDevice "microbel" {
+    interfaceGroups = [ [ "eth0" ] ];
+  };
+  nodes.innovation = mkDevice "innovation" {
+    hardware.info = "Dell Optiplex 9010";
+    interfaceGroups = [ [ "em0" ] ];
+    interfaces.em0 = {
+      mac = "18:03:73:20:18:d3";
+      addresses = [
+        "129.241.210.214"
+        "2001:700:300:1900::1:56"
+      ];
+      gateways = [
+        "129.241.210.129"
+        "2001:700:300:1900::1"
+      ];
+    };
+    services = {
+      minecraft = {
+        name = "Minecraft";
+        icon = "services.minecraft";
+        info = "minecraft.pvv.ntnu.no";
+        details.listen.text = "0.0.0.0:25565";
+      };
+    };
+  };
+  nodes.principal = mkDevice "principal" {
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.sleipner = mkDevice "sleipner" {
+    interfaceGroups = [ [ "eno0" "enp2s0" ] ];
+  };
+  nodes.isvegg = mkDevice "isvegg" {
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.ameno = mkDevice "ameno" {
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.skrott = mkDevice "skrott" {
+    deviceType = "terminal";
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.torskas = mkDevice "torskas" {
+    deviceType = "terminal";
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.wegonke = mkDevice "wegonke" {
+    deviceType = "terminal";
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.demiurgen = mkDevice "demiurgen" {
+    deviceType = "terminal";
+    interfaceGroups = [ [ ] ];
+  };
+  nodes.sanctuary = mkDevice "sanctuary" {
+    deviceType = "terminal";
+    interfaceGroups = [ [ ] ];
+  };
+}

topology/service-extractors/greg-ng.nix

@@ -0,0 +1,11 @@
+{ config, lib, ... }:
+let
+  cfg = config.services.greg-ng or { enable = false; };
+in
+{
+  config.topology.self.services.greg-ng = lib.mkIf cfg.enable {
+    name = "Greg-ng";
+    icon = ../icons/greg-ng.png;
+    details.listen = { text = "${cfg.settings.host}:${toString cfg.settings.port}"; };
+  };
+}