feat(docs): add missing step from setting up hils

docs/src/hil/nixos-setup.md

@@ -3,6 +3,32 @@
 Eventually, we will support fully automating the setup process. But *for now*,
 one first needs to do some manual bootstrapping.
 
+## Setting up nix flake
+
+This step is a common way to create a nix flake for HILs.
+
+- Choose a hostname for you HIL. The convention we use is incremental `worldcoin-hil-[location]-[number]` (see `orb-software/nix/machines`)
+- Inside `nix/machines` Copy an existing HIL flake with your hostname
+
+```sh
+cp -r worldcoin-hil-munich-0 worldcoin-hil-munich-[your-number]
+```
+
+- Update `nix/machines/flake-outputs.nix` with the new hostname (make sure formatting is correct otherwise CI will fail on the PR)
+
+```nix
+...
+nixosConfigurations."worldcoin-hil-munich-8" = hilConfig {
+    hostname = "worldcoin-hil-munich-8";
+  };
+# Your new configuration HERE
+
+nixosConfigurations."worldcoin-hil-munich-[your-number]" = hilConfig {
+    hostname = "worldcoin-hil-munich-[your-number]";
+  };
+```
+
+- Open a PR in `orb-software` with your changes and merge before the next steps
 
 ## Installing NixOS to a liveusb
 
@@ -11,8 +37,8 @@ inexplicable reason the official NixOS installer *only* exists as a MBR partitio
 disk. This means we need to build our own GPT/UEFI based NixOS live usb ;(
 
 To work around this limitation of the official installer, we provide a liveusb
-image that has NixOS on it, via [disko][disko]. The easiest way to get this liveusb image
-is from the CI artifacts, it is built by the [Nix CI][nix ci] job.
+image that has NixOS on it, via [disko]. The easiest way to get this liveusb image
+is from the CI artifacts, it is built by the [Nix CI] job.
 
 Once you download it, unzip it, and `gzip --decompress liveusb.raw.gz` it. You will now
 have a `liveusb.raw` file. Plug your flashdrive in, identity the *disk* (not partition) of
@@ -24,8 +50,8 @@ Run the following:
 ```bash
 sudo cp liveusb.raw /dev/<your-usb-disk>
 ```
-This loads the liveusb onto the flashdrive.
 
+This loads the liveusb onto the flashdrive.
 
 ## Use the liveusb to install NixOS
 
@@ -71,9 +97,11 @@ there.
 
 Run the following in the HIL. It will print a url to the console when its the first time on this
 machine.
+
 ```bash
 sudo tailscale up
 ```
+
 Go to the URL on your laptop, log in with your tfh google account. This will connect
 the device to the tailscale network. From this point forward, any other computer that
 is connected to tailscale will also be able to ssh into the HIL, even without teleport.
@@ -89,13 +117,16 @@ cloudflare warp is turned off, as it can conflict with the tailscale VPN.
 1. Request teleport token for a HIL in slack. You will receive a bash one-liner.
 
 **DO NOT RUN THE BASH, THIS IS AN EXAMPLE:**
+
 ```bash
 sudo bash -c "$(curl -fsSL https://teleport-cluster.orb.internal-tools.worldcoin.dev/scripts/ffffffffffffffffffffffffffffffff/install-node.sh)"
 ```
+
 The command you received on slack should look like something of the above.
 
 Instead of running the command, delete everything except the `curl` command and then
 redirect that to a file called `teleport-install.sh`, for example:
+
 ```bash
 curl -fsSL https://teleport-cluster.orb.internal-tools.worldcoin.dev/scripts/ffffffffffffffffffffffffffffffff/install-node.sh > teleport-install.sh
 
@@ -105,6 +136,7 @@ Be sure that `teleport-install.sh` is put on the HIL, you can put it in the home
 for now. Again, *DO NOT RUN THIS SCRIPT*.
 
 2. Place the following content on the HIL at `/etc/teleport.yaml`:
+
 ```yaml
 version: v3
 teleport:
@@ -136,20 +168,22 @@ proxy_service:
 ```
 
 3. run the following from the same directory that `teleport-install.sh` is at on the
-HIL:
+   HIL:
+
 ```bash
 TELEPORT_TOKEN="$(cat teleport-install.sh | grep -m1 -oP "^JOIN_TOKEN='\K[^']+")" && [ -n "${TELEPORT_TOKEN}" ] || echo "error: token not found"
 TELEPORT_HOSTNAME="$(hostname)"
 sudo sed -i "s/SED_TOKEN/${TELEPORT_TOKEN}/" /etc/teleport.yaml
 sudo sed -i "s/SED_HOSTNAME/${TELEPORT_HOSTNAME}/" /etc/teleport.yaml
-````
+```
 
 This will edit the contents of `/etc/teleport.yaml` to replace the `SED_*` strings with
 your hostname and the token.
 
 You can `sudo cat /etc/teleport.yaml` and inspect the file to see the new contents.
 
-4. Run 
+4. Run
+
 ```bash
 sudo rm -rf /var/lib/teleport
 sudo systemctl restart teleport.service && sudo journalctl -fu teleport.service
@@ -161,9 +195,6 @@ is normal. Teleport should now be set up.
 You will also need to make sure your machine's hostname matches the regex in our
 terraform config [here][tf hil].
 
-
-[nix config]: https://github.com/TheButlah/nix
-[remote build]: https://nix.dev/manual/nix/2.18/advanced-topics/distributed-builds
 [disko]: https://github.com/nix-community/disko
-[tf hil]: https://github.com/worldcoin/infrastructure/blob/345bc7db0c47e369ce6529d0febed9535a0970f7/teleport/orb/orb-sw-dev-tools-teleport.tf
 [nix ci]: https://github.com/worldcoin/orb-software/actions/workflows/nix-ci.yaml
+[tf hil]: https://github.com/worldcoin/infrastructure/blob/345bc7db0c47e369ce6529d0febed9535a0970f7/teleport/orb/orb-sw-dev-tools-teleport.tf