6 files changed, 1243 insertions, 0 deletions
diff --git a/users/tazjin/nixos/README.md b/users/tazjin/nixos/README.md
new file mode 100644
index 000000000000..662f2a36acac
--- /dev/null
+++ b/users/tazjin/nixos/README.md
@@ -0,0 +1,17 @@
+NixOS configuration
+===================
+
+My NixOS configurations! It configures most of the packages I require
+on my systems, sets up Emacs the way I need and does a bunch of other
+interesting things.
+
+System configuration lives in folders, and some of the modules stem
+from `//ops/modules`.
+
+Machines are deployed with the script at `ops.nixos.rebuild-system`.
+
+## Configured hosts:
+
+* `tverskoy` - X13 AMD that's travelling around with me
+* `frog` - weapon of mass computation (in storage in London)
+* `camden` - NUC formerly serving tazj.in (in storage in London)
diff --git a/users/tazjin/nixos/camden/default.nix b/users/tazjin/nixos/camden/default.nix
new file mode 100644
index 000000000000..b8b8e25fc3f4
--- /dev/null
+++ b/users/tazjin/nixos/camden/default.nix
@@ -0,0 +1,361 @@
+# This file configures camden.tazj.in, my homeserver.
+{ depot, pkgs, lib, ... }:
+
+config:
+let
+  nginxRedirect = { from, to, acmeHost }: {
+    serverName = from;
+    useACMEHost = acmeHost;
+    forceSSL = true;
+
+    extraConfig = "return 301 https://${to}$request_uri;";
+  };
+in
+lib.fix (self: {
+  # Disable the current ACME module and use the old one from 19.09
+  # instead, until the various regressions have been sorted out.
+  # TODO(tazjin): Remove this once the new ACME module works.
+  disabledModules = [ "security/acme" ];
+  imports =
+    let
+      oldChannel = fetchTarball {
+        # NixOS 19.09 on 2020-10-04
+        url = "https://github.com/NixOS/nixpkgs-channels/archive/75f4ba05c63be3f147bcc2f7bd4ba1f029cedcb1.tar.gz";
+        sha256 = "157c64220lf825ll4c0cxsdwg7cxqdx4z559fdp7kpz0g6p8fhhr";
+      };
+    in
+    [
+      "${depot.path}/ops/modules/quassel.nix"
+      "${depot.path}/ops/modules/smtprelay.nix"
+      "${oldChannel}/nixos/modules/security/acme.nix"
+    ];
+
+  # camden is intended to boot unattended, despite having an encrypted
+  # root partition.
+  #
+  # The below configuration uses an externally connected USB drive
+  # that contains a LUKS key file to unlock the disk automatically at
+  # boot.
+  #
+  # TODO(tazjin): Configure LUKS unlocking via SSH instead.
+  boot = {
+    initrd = {
+      availableKernelModules = [
+        "ahci"
+        "xhci_pci"
+        "usbhid"
+        "usb_storage"
+        "sd_mod"
+        "sdhci_pci"
+        "rtsx_usb_sdmmc"
+        "r8169"
+      ];
+
+      kernelModules = [ "dm-snapshot" ];
+
+      luks.devices.camden-crypt = {
+        fallbackToPassword = true;
+        device = "/dev/disk/by-label/camden-crypt";
+        keyFile = "/dev/sdb";
+        keyFileSize = 4096;
+      };
+    };
+
+    loader = {
+      systemd-boot.enable = true;
+      efi.canTouchEfiVariables = true;
+    };
+
+    cleanTmpDir = true;
+  };
+
+  fileSystems = {
+    "/" = {
+      device = "/dev/disk/by-label/camden-root";
+      fsType = "ext4";
+    };
+
+    "/home" = {
+      device = "/dev/disk/by-label/camden-home";
+      fsType = "ext4";
+    };
+
+    "/boot" = {
+      device = "/dev/disk/by-label/BOOT";
+      fsType = "vfat";
+    };
+  };
+
+  nix = {
+    maxJobs = lib.mkDefault 4;
+
+    trustedUsers = [ "root" "tazjin" ];
+
+    binaryCaches = [
+      "https://tazjin.cachix.org"
+    ];
+
+    binaryCachePublicKeys = [
+      "tazjin.cachix.org-1:IZkgLeqfOr1kAZjypItHMg1NoBjm4zX9Zzep8oRSh7U="
+    ];
+  };
+
+  powerManagement.cpuFreqGovernor = lib.mkDefault "powersave";
+
+  networking = {
+    hostName = "camden";
+    interfaces.enp1s0.useDHCP = true;
+    interfaces.enp1s0.ipv6.addresses = [
+      {
+        address = "2a01:4b00:821a:ce02::5";
+        prefixLength = 64;
+      }
+    ];
+
+    firewall.enable = false;
+  };
+
+  time.timeZone = "UTC";
+
+  # System-wide application setup
+  programs.fish.enable = true;
+  programs.mosh.enable = true;
+
+  fonts = {
+    fonts = [ pkgs.jetbrains-mono ];
+    fontconfig.defaultFonts.monospace = [ "JetBrains Mono" ];
+  };
+
+  environment.systemPackages =
+    # programs from the depot
+    (with depot; [
+      fun.idual.script
+      fun.idual.setAlarm
+    ]) ++
+
+    # programs from nixpkgs
+    (with pkgs; [
+      bat
+      curl
+      direnv
+      emacs27-nox
+      fswebcam
+      git
+      gnupg
+      google-cloud-sdk
+      htop
+      jq
+      pass
+      pciutils
+      restic
+      ripgrep
+      screen
+    ]);
+
+  users = {
+    # Set up my own user for logging in and doing things ...
+    users.tazjin = {
+      isNormalUser = true;
+      uid = 1000;
+      extraGroups = [ "git" "wheel" "quassel" "video" ];
+      shell = pkgs.fish;
+    };
+
+    # Set up a user & group for general git shenanigans
+    groups.git = { };
+    users.git = {
+      group = "git";
+      isSystemUser = true;
+    };
+  };
+
+  # Services setup
+  services.openssh.enable = true;
+  services.haveged.enable = true;
+
+  # Join Tailscale into home network
+  services.tailscale.enable = true;
+
+  # Allow sudo-ing via the forwarded SSH agent.
+  security.pam.enableSSHAgentAuth = true;
+
+  # NixOS 20.03 broke nginx and I can't be bothered to debug it
+  # anymore, all solution attempts have failed, so here's a
+  # brute-force fix.
+  systemd.services.fix-nginx = {
+    script = "${pkgs.coreutils}/bin/chown -R nginx: /var/spool/nginx /var/cache/nginx";
+
+    serviceConfig = {
+      User = "root";
+      Type = "oneshot";
+    };
+  };
+
+  systemd.timers.fix-nginx = {
+    wantedBy = [ "multi-user.target" ];
+    timerConfig = {
+      OnCalendar = "minutely";
+    };
+  };
+
+  # Provision a TLS certificate outside of nginx to avoid
+  # nixpkgs#38144
+  security.acme = {
+    # acceptTerms = true;
+
+    certs."tazj.in" = {
+      email = "mail@tazj.in";
+      user = "nginx";
+      group = "nginx";
+      webroot = "/var/lib/acme/acme-challenge";
+      extraDomains = {
+        "cs.tazj.in" = null;
+        "git.tazj.in" = null;
+        "www.tazj.in" = null;
+
+        # Local domains (for this machine only)
+        "camden.tazj.in" = null;
+      };
+      postRun = "systemctl reload nginx";
+    };
+
+    certs."quassel.tazj.in" = {
+      email = "mail@tazj.in";
+      webroot = "/var/lib/acme/challenge-quassel";
+      user = "nginx"; # required because of a bug in the ACME module
+      group = "quassel";
+      allowKeysForGroup = true;
+    };
+  };
+
+  # Forward logs to Google Cloud Platform
+  services.journaldriver = {
+    enable = true;
+    logStream = "home";
+    googleCloudProject = "tazjins-infrastructure";
+    applicationCredentials = "/etc/gcp/key.json";
+  };
+
+  services.depot.quassel = {
+    enable = true;
+    acmeHost = "quassel.tazj.in";
+    bindAddresses = [
+      "0.0.0.0"
+    ];
+  };
+
+  services.bitlbee = {
+    enable = false;
+    portNumber = 2337; # bees
+  };
+
+  # serve my website(s)
+  services.nginx = {
+    enable = true;
+    enableReload = true;
+    package = with pkgs; nginx.override {
+      modules = [ nginxModules.rtmp ];
+    };
+
+    recommendedTlsSettings = true;
+    recommendedGzipSettings = true;
+    recommendedProxySettings = true;
+
+    appendConfig = ''
+      rtmp_auto_push on;
+      rtmp {
+        server {
+          listen 1935;
+          chunk_size 4000;
+
+          application tvl {
+            live on;
+
+            allow publish 88.98.195.213;
+            allow publish 10.0.1.0/24;
+            deny publish all;
+
+            allow play all;
+          }
+        }
+      }
+    '';
+
+    commonHttpConfig = ''
+      log_format json_combined escape=json
+      '{'
+          '"remote_addr":"$remote_addr",'
+          '"method":"$request_method",'
+          '"uri":"$request_uri",'
+          '"status":$status,'
+          '"request_size":$request_length,'
+          '"response_size":$body_bytes_sent,'
+          '"response_time":$request_time,'
+          '"referrer":"$http_referer",'
+          '"user_agent":"$http_user_agent"'
+      '}';
+
+      access_log syslog:server=unix:/dev/log,nohostname json_combined;
+    '';
+
+    virtualHosts.homepage = {
+      serverName = "tazj.in";
+      serverAliases = [ "camden.tazj.in" ];
+      default = true;
+      useACMEHost = "tazj.in";
+      root = depot.users.tazjin.homepage;
+      forceSSL = true;
+
+      extraConfig = ''
+        ${depot.users.tazjin.blog.oldRedirects}
+
+        add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload" always;
+
+        location ~* \.(webp|woff2)$ {
+          add_header Cache-Control "public, max-age=31536000";
+        }
+
+        location /blog/ {
+          alias ${depot.users.tazjin.blog.rendered}/;
+
+          if ($request_uri ~ ^/(.*)\.html$) {
+            return 302 /$1;
+          }
+
+          try_files $uri $uri.html $uri/ =404;
+        }
+
+        location = /tazjin {
+          return 200 "tazjin";
+        }
+
+        location /blobs/ {
+          alias /var/www/blobs/;
+        }
+      '';
+    };
+
+    virtualHosts.cgit-old = nginxRedirect {
+      from = "git.tazj.in";
+      to = "code.tvl.fyi";
+      acmeHost = "tazj.in";
+    };
+
+    virtualHosts.cs-old = nginxRedirect {
+      from = "cs.tazj.in";
+      to = "cs.tvl.fyi";
+      acmeHost = "tazj.in";
+    };
+  };
+
+  # Timer units that can be started with systemd-run to set my alarm.
+  systemd.user.services.light-alarm = {
+    script = "${depot.fun.idual.script}/bin/idualctl wakey";
+    postStart = "${pkgs.systemd}/bin/systemctl --user stop light-alarm.timer";
+    serviceConfig = {
+      Type = "oneshot";
+    };
+  };
+
+  system.stateVersion = "19.09";
+})
diff --git a/users/tazjin/nixos/default.nix b/users/tazjin/nixos/default.nix
new file mode 100644
index 000000000000..e240eada534a
--- /dev/null
+++ b/users/tazjin/nixos/default.nix
@@ -0,0 +1,9 @@
+{ depot, lib, ... }:
+
+let systemFor = sys: (depot.ops.nixos.nixosFor sys).system;
+in depot.nix.readTree.drvTargets {
+  camdenSystem = systemFor depot.users.tazjin.nixos.camden;
+  frogSystem = systemFor depot.users.tazjin.nixos.frog;
+  tverskoySystem = systemFor depot.users.tazjin.nixos.tverskoy;
+  polyankaSystem = (depot.ops.nixos.nixosFor depot.users.tazjin.nixos.polyanka).system;
+}
diff --git a/users/tazjin/nixos/frog/default.nix b/users/tazjin/nixos/frog/default.nix
new file mode 100644
index 000000000000..8e356dd41eaa
--- /dev/null
+++ b/users/tazjin/nixos/frog/default.nix
@@ -0,0 +1,287 @@
+{ depot, lib, pkgs, ... }:
+
+config:
+let
+  inherit (pkgs) lieer;
+
+  quasselClient = pkgs.quassel.override {
+    client = true;
+    enableDaemon = false;
+    monolithic = false;
+  };
+in
+lib.fix (self: {
+  imports = [
+    "${depot.path}/ops/modules/v4l2loopback.nix"
+  ];
+
+  boot = {
+    tmpOnTmpfs = true;
+    kernelModules = [ "kvm-amd" ];
+
+    loader = {
+      systemd-boot.enable = true;
+      efi.canTouchEfiVariables = true;
+    };
+
+    initrd = {
+      luks.devices.frog-crypt.device = "/dev/disk/by-label/frog-crypt";
+      availableKernelModules = [ "xhci_pci" "ahci" "nvme" "usb_storage" "usbhid" "sd_mod" ];
+      kernelModules = [ "dm-snapshot" ];
+    };
+
+    kernelPackages = pkgs.linuxPackages_latest;
+    kernel.sysctl = {
+      "kernel.perf_event_paranoid" = -1;
+    };
+
+    # Enable this again if frog is put back into use ...
+    #
+    # kernelPatches = [
+    #   depot.third_party.kernelPatches.trx40_usb_audio
+    # ];
+  };
+
+  hardware = {
+    cpu.amd.updateMicrocode = true;
+    enableRedistributableFirmware = true;
+    opengl = {
+      enable = true;
+      driSupport = true;
+      driSupport32Bit = true;
+    };
+
+    pulseaudio = {
+      enable = true;
+      package = pkgs.pulseaudioFull;
+    };
+
+    bluetooth = {
+      enable = true;
+    };
+  };
+
+  nix = {
+    maxJobs = 48;
+    binaryCaches = [ "ssh://nix-ssh@whitby.tvl.fyi" ];
+    binaryCachePublicKeys = [ "cache.tvl.fyi:fd+9d1ceCPvDX/xVhcfv8nAa6njEhAGAEe+oGJDEeoc=" ];
+  };
+
+  networking = {
+    hostName = "frog";
+    useDHCP = true;
+
+    # Don't use ISP's DNS servers:
+    nameservers = [
+      "8.8.8.8"
+      "8.8.4.4"
+    ];
+
+    firewall.enable = false;
+  };
+
+  # Generate an immutable /etc/resolv.conf from the nameserver settings
+  # above (otherwise DHCP overwrites it):
+  environment.etc."resolv.conf" = with lib; {
+    source = pkgs.writeText "resolv.conf" ''
+      ${concatStringsSep "\n" (map (ns: "nameserver ${ns}") self.networking.nameservers)}
+      options edns0
+    '';
+  };
+
+  time.timeZone = "Europe/London";
+
+  fileSystems = {
+    "/".device = "/dev/disk/by-label/frog-root";
+    "/boot".device = "/dev/disk/by-label/BOOT";
+    "/home".device = "/dev/disk/by-label/frog-home";
+  };
+
+  # Configure user account
+  users.extraUsers.tazjin = {
+    extraGroups = [ "wheel" "audio" "docker" ];
+    isNormalUser = true;
+    uid = 1000;
+    shell = pkgs.fish;
+  };
+
+  security.sudo = {
+    enable = true;
+    extraConfig = "wheel ALL=(ALL:ALL) SETENV: ALL";
+  };
+
+  fonts = {
+    fonts = with pkgs; [
+      corefonts
+      dejavu_fonts
+      jetbrains-mono
+      noto-fonts-cjk
+      noto-fonts-emoji
+    ];
+
+    fontconfig = {
+      hinting.enable = true;
+      subpixel.lcdfilter = "light";
+
+      defaultFonts = {
+        monospace = [ "JetBrains Mono" ];
+      };
+    };
+  };
+
+  # Configure location (Vauxhall, London) for services that need it.
+  location = {
+    latitude = 51.4819109;
+    longitude = -0.1252998;
+  };
+
+  programs.fish.enable = true;
+  programs.ssh.startAgent = true;
+
+  services.redshift.enable = true;
+  services.openssh.enable = true;
+  services.fstrim.enable = true;
+  services.blueman.enable = true;
+
+  # Required for Yubikey usage as smartcard
+  services.pcscd.enable = true;
+  services.udev.packages = [
+    pkgs.yubikey-personalization
+  ];
+
+  # Enable Docker for Nixery testing
+  virtualisation.docker = {
+    enable = true;
+    autoPrune.enable = true;
+  };
+
+  services.xserver = {
+    enable = true;
+    layout = "us";
+    xkbOptions = "caps:super";
+    exportConfiguration = true;
+    videoDrivers = [ "amdgpu" ];
+    displayManager = {
+      # Give EXWM permission to control the session.
+      sessionCommands = "${pkgs.xorg.xhost}/bin/xhost +SI:localuser:$USER";
+
+      lightdm.enable = true;
+      lightdm.greeters.gtk.clock-format = "%H·%M"; # TODO(tazjin): TZ?
+    };
+
+    windowManager.session = lib.singleton {
+      name = "exwm";
+      start = "${depot.users.tazjin.emacs}/bin/tazjins-emacs";
+    };
+  };
+
+  # Do not restart the display manager automatically
+  systemd.services.display-manager.restartIfChanged = lib.mkForce false;
+
+  # clangd needs more than ~2GB in the runtime directory to start up
+  services.logind.extraConfig = ''
+    RuntimeDirectorySize=16G
+  '';
+
+  # Configure email setup
+  systemd.user.services.lieer-tazjin = {
+    description = "Synchronise mail@tazj.in via lieer";
+    script = "${lieer}/bin/gmi sync";
+
+    serviceConfig = {
+      WorkingDirectory = "%h/mail/account.tazjin";
+      Type = "oneshot";
+    };
+  };
+
+  systemd.user.timers.lieer-tazjin = {
+    wantedBy = [ "timers.target" ];
+
+    timerConfig = {
+      OnActiveSec = "1";
+      OnUnitActiveSec = "180";
+    };
+  };
+
+  environment.systemPackages =
+    # programs from the depot
+    (with depot; [
+      fun.idual.script
+      fun.uggc
+      lieer
+      ops.kontemplate
+      quasselClient
+      third_party.git
+      tools.nsfv-setup
+      users.tazjin.emacs
+    ]) ++
+
+    # programs from nixpkgs
+    (with pkgs; [
+      age
+      bat
+      chromium
+      clang-manpages
+      clang-tools_11
+      clang_11
+      curl
+      direnv
+      dnsutils
+      emacs27 # mostly for emacsclient
+      exa
+      fd
+      file
+      gdb
+      gnupg
+      go
+      google-chrome
+      google-cloud-sdk
+      htop
+      hyperfine
+      i3lock
+      iftop
+      imagemagick
+      jq
+      kubectl
+      linuxPackages.perf
+      man-pages
+      miller
+      msmtp
+      nix-prefetch-github
+      notmuch
+      obs-studio
+      openssh
+      openssl
+      pass
+      pavucontrol
+      pciutils
+      pinentry
+      pinentry-emacs
+      pmutils
+      pwgen
+      ripgrep
+      rustup
+      screen
+      scrot
+      spotify
+      tokei
+      transmission
+      tree
+      unzip
+      usbutils
+      v4l-utils
+      vlc
+      xclip
+      xsecurelock
+      yubico-piv-tool
+      yubikey-personalization
+      zoxide
+
+      # Commented out because of interim breakage:
+      # steam
+      # lutris
+    ]);
+
+  # ... and other nonsense.
+  system.stateVersion = "20.03";
+})
diff --git a/users/tazjin/nixos/polyanka/default.nix b/users/tazjin/nixos/polyanka/default.nix
new file mode 100644
index 000000000000..476e3fd13af2
--- /dev/null
+++ b/users/tazjin/nixos/polyanka/default.nix
@@ -0,0 +1,124 @@
+# VPS hosted at GleSYS, running my Quassel and some random network
+# stuff.
+
+_: # ignore readTree options
+
+{ config, depot, lib, pkgs, ... }:
+
+let
+  mod = name: depot.path + ("/ops/modules/" + name);
+in
+{
+  imports = [
+    (mod "quassel.nix")
+  ];
+
+  # Use the GRUB 2 boot loader.
+  boot.loader.grub.enable = true;
+  boot.loader.grub.version = 2;
+  boot.loader.grub.device = "/dev/sda"; # or "nodev" for efi only
+  boot.initrd.availableKernelModules = [ "ata_piix" "vmw_pvscsi" "sd_mod" "sr_mod" ];
+
+  virtualisation.vmware.guest.enable = true;
+  virtualisation.vmware.guest.headless = true;
+
+  nix.settings.trusted-users = [ "tazjin" ];
+
+  # Work around strongswan 5.9.4 being incompatible with servers not
+  # patched against some CVE. I need this for work ..
+  nixpkgs.overlays = [
+    depot.third_party.overlays.strongswan-workaround
+  ];
+
+  fileSystems."/" =
+    {
+      device = "/dev/disk/by-uuid/4c51357a-1e34-4b59-b169-63af1fcdce71";
+      fsType = "ext4";
+    };
+
+  networking = {
+    hostName = "polyanka";
+    domain = "tazj.in";
+    useDHCP = false;
+
+    # Required for VPN usage
+    networkmanager.enable = true;
+
+    interfaces.ens192 = {
+      ipv4.addresses = lib.singleton {
+        address = "159.253.30.129";
+        prefixLength = 24;
+      };
+
+      ipv6.addresses = lib.singleton {
+        address = "2a02:750:7:3305::308";
+        prefixLength = 64;
+      };
+    };
+
+    defaultGateway = "159.253.30.1";
+    defaultGateway6.address = "2a02:750:7:3305::1";
+
+    firewall.enable = true;
+
+    nameservers = [
+      "79.99.4.100"
+      "79.99.4.101"
+      "2a02:751:aaaa::1"
+      "2a02:751:aaaa::2"
+    ];
+  };
+
+  time.timeZone = "UTC";
+
+  security.acme.acceptTerms = true;
+  security.acme.certs."polyanka.tazj.in" = {
+    listenHTTP = ":80";
+    email = "mail@tazj.in";
+    group = "quassel";
+  };
+
+  users.users.tazjin = {
+    isNormalUser = true;
+    extraGroups = [ "wheel" ];
+    shell = pkgs.fish;
+    openssh.authorizedKeys.keys = [
+      "sk-ecdsa-sha2-nistp256@openssh.com AAAAInNrLWVjZHNhLXNoYTItbmlzdHAyNTZAb3BlbnNzaC5jb20AAAAIbmlzdHAyNTYAAABBBAWvA3RpXpMAqruUbB+eVgvvHCzhs5R9khFRza3YSLeFiIqOxVVgyhzW/BnCSD9t/5JrqRdJIGQLnkQU9m4REhUAAAAEc3NoOg== tazjin@tverskoy"
+      "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIM1fGWz/gsq+ZeZXjvUrV+pBlanw1c3zJ9kLTax9FWQy tazjin@tverskoy"
+    ];
+  };
+
+  security.sudo.wheelNeedsPassword = false;
+
+  services.depot.quassel = {
+    enable = true;
+    acmeHost = "polyanka.tazj.in";
+    bindAddresses = [
+      "0.0.0.0"
+    ];
+  };
+
+  # List packages installed in system profile. To search, run:
+  # $ nix search wget
+  environment.systemPackages = with pkgs; [
+    curl
+    htop
+    jq
+    nmap
+    bat
+    emacs-nox
+    nano
+    wget
+  ];
+
+  programs.mtr.enable = true;
+  programs.mosh.enable = true;
+  services.openssh.enable = true;
+
+  services.zerotierone.enable = true;
+  services.zerotierone.joinNetworks = [
+    "35c192ce9bd4c8c7"
+  ];
+
+  system.stateVersion = "20.09";
+}
diff --git a/users/tazjin/nixos/tverskoy/default.nix b/users/tazjin/nixos/tverskoy/default.nix
new file mode 100644
index 000000000000..75f99dacca13
--- /dev/null
+++ b/users/tazjin/nixos/tverskoy/default.nix
@@ -0,0 +1,445 @@
+{ depot, lib, pkgs, ... }:
+
+config:
+let
+  quasselClient = pkgs.quassel.override {
+    client = true;
+    enableDaemon = false;
+    monolithic = false;
+  };
+
+  # Use a screen lock command that resets the keyboard layout
+  # before locking, to avoid locking me out when the layout is
+  # in Russian.
+  screenLock = pkgs.writeShellScriptBin "tazjin-screen-lock" ''
+    ${pkgs.xorg.setxkbmap}/bin/setxkbmap us
+    ${pkgs.xorg.setxkbmap}/bin/setxkbmap -option caps:super
+    exec ${pkgs.xsecurelock}/bin/xsecurelock
+  '';
+in
+lib.fix (self: {
+  imports = [
+    "${depot.third_party.impermanence}/nixos.nix"
+    "${pkgs.home-manager.src}/nixos"
+  ];
+
+  tvl.cache.enable = true;
+
+  # Work around strongswan 5.9.4 being incompatible with servers not
+  # patched against some CVE. I need this for work ..
+  nixpkgs.overlays = [
+    depot.third_party.overlays.strongswan-workaround
+  ];
+
+  boot = rec {
+    initrd.availableKernelModules = [ "nvme" "ehci_pci" "xhci_pci" "usb_storage" "sd_mod" "rtsx_pci_sdmmc" ];
+    initrd.kernelModules = [ ];
+
+    # Restore /home to the blank snapshot, erasing all ephemeral data.
+    initrd.postDeviceCommands = lib.mkAfter ''
+      zfs rollback -r zpool/ephemeral/home@tazjin-clean
+    '';
+
+    # Install thinkpad modules for TLP
+    extraModulePackages = [ kernelPackages.acpi_call ];
+
+    kernelModules = [ "kvm-amd" "i2c_dev" ];
+    kernelPackages = pkgs.linuxPackages_latest;
+    loader.systemd-boot.enable = true;
+    loader.efi.canTouchEfiVariables = true;
+    zfs.enableUnstable = true;
+  };
+
+  fileSystems = {
+    "/" = {
+      device = "tmpfs";
+      fsType = "tmpfs";
+      options = [ "defaults" "size=8G" "mode=755" ];
+    };
+
+    "/home" = {
+      device = "zpool/ephemeral/home";
+      fsType = "zfs";
+    };
+
+    "/nix" = {
+      device = "zpool/local/nix";
+      fsType = "zfs";
+    };
+
+    "/depot" = {
+      device = "zpool/safe/depot";
+      fsType = "zfs";
+    };
+
+    "/persist" = {
+      device = "zpool/safe/persist";
+      fsType = "zfs";
+      neededForBoot = true;
+    };
+
+    # SD card
+    "/mnt" = {
+      device = "/dev/disk/by-uuid/c602d703-f1b9-4a44-9e45-94dfe24bdaa8";
+      fsType = "ext4";
+    };
+
+    "/boot" = {
+      device = "/dev/disk/by-uuid/BF4F-388B";
+      fsType = "vfat";
+    };
+  };
+
+  hardware = {
+    cpu.amd.updateMicrocode = true;
+    enableRedistributableFirmware = true;
+    bluetooth.enable = true;
+
+    opengl = {
+      enable = true;
+      extraPackages = with pkgs; [
+        vaapiVdpau
+        libvdpau-va-gl
+      ];
+    };
+  };
+
+  networking = {
+    hostName = "tverskoy";
+    hostId = "3c91827f";
+    domain = "tvl.su";
+    useDHCP = false;
+    networkmanager.enable = true;
+    firewall.enable = false;
+
+    nameservers = [
+      "8.8.8.8"
+      "8.8.4.4"
+    ];
+  };
+
+  fonts = {
+    fonts = with pkgs; [
+      corefonts
+      dejavu_fonts
+      jetbrains-mono
+      noto-fonts-cjk
+      noto-fonts-emoji
+    ];
+
+    fontconfig = {
+      hinting.enable = true;
+      subpixel.lcdfilter = "light";
+
+      defaultFonts = {
+        monospace = [ "JetBrains Mono" ];
+      };
+    };
+  };
+
+  environment.persistence."/persist" = {
+    directories = [
+      "/etc/NetworkManager/system-connections"
+      "/etc/mullvad-vpn"
+      "/var/cache/mullvad-vpn"
+      "/var/lib/bluetooth"
+      "/var/lib/systemd/coredump"
+      "/var/lib/tailscale"
+      "/var/lib/zerotier-one"
+      "/var/log"
+    ];
+
+    files = [
+      "/etc/machine-id"
+    ];
+  };
+
+  # from https://github.com/NixOS/nixpkgs/issues/64965
+  environment.etc."ipsec.secrets".text = ''
+    include ipsec.d/ipsec.nm-l2tp.secrets
+  '';
+
+  security.rtkit.enable = true;
+
+  services = {
+    pipewire = {
+      enable = true;
+      alsa.enable = true;
+      pulse.enable = true;
+    };
+
+    redshift.enable = true;
+    blueman.enable = true;
+    mullvad-vpn.enable = true;
+    fwupd.enable = true;
+    printing.enable = true;
+
+    # expose i2c device as /dev/i2c-amdgpu-dm and make it user-accessible
+    # this is required for sending control commands to the Dasung screen.
+    udev.extraRules = ''
+      SUBSYSTEM=="i2c-dev", ACTION=="add", DEVPATH=="/devices/pci0000:00/0000:00:08.1/0000:06:00.0/i2c-5/i2c-dev/i2c-5", SYMLINK+="i2c-amdgpu-dm", TAG+="uaccess"
+    '';
+
+    # Enable power-saving features.
+    tlp.enable = true;
+
+    xserver = {
+      enable = true;
+      layout = "us";
+      xkbOptions = "caps:super";
+      videoDrivers = [ "amdgpu" ];
+
+      libinput.enable = true;
+
+      displayManager = {
+        # Give EXWM permission to control the session.
+        sessionCommands = "${pkgs.xorg.xhost}/bin/xhost +SI:localuser:$USER";
+        lightdm.enable = true;
+        # lightdm.greeters.gtk.clock-format = "%H:%M"; # TODO(tazjin): TZ?
+      };
+
+      windowManager.session = lib.singleton {
+        name = "exwm";
+        start = "${depot.users.tazjin.emacs}/bin/tazjins-emacs";
+      };
+    };
+
+    # Automatically collect garbage from the Nix store.
+    depot.automatic-gc = {
+      enable = true;
+      interval = "1 hour";
+      diskThreshold = 16; # GiB
+      maxFreed = 10; # GiB
+      preserveGenerations = "14d";
+    };
+  };
+
+  # Set variables to enable EXWM-XIM
+  environment.sessionVariables = {
+    XMODIFIERS = "@im=exwm-xim";
+    GTK_IM_MODULE = "xim";
+    QT_IM_MODULE = "xim";
+    CLUTTER_IM_MODULE = "xim";
+  };
+
+  # Automatically detect location to use for redshift
+  location.provider = "geoclue2";
+
+  # Do not restart the display manager automatically
+  systemd.services.display-manager.restartIfChanged = lib.mkForce false;
+
+  # If something needs more than 10s to stop it should probably be
+  # killed.
+  systemd.extraConfig = ''
+    DefaultTimeoutStopSec=10s
+  '';
+
+  time.timeZone = "Africa/Cairo";
+
+  nix = {
+    trustedUsers = [ "tazjin" ];
+  };
+
+  users.users.tazjin = {
+    isNormalUser = true;
+    createHome = true;
+    extraGroups = [ "wheel" "networkmanager" "video" "adbusers" ];
+    uid = 1000;
+    shell = pkgs.fish;
+    initialHashedPassword = "$6$d3FywUNCuZnJ4l.$ZW2ul59MLYon1v1xhC3lTJZfZ91lWW6Tpi13MpME0cJcYZNrsx7ABdgQRn.K05awruG2Y9ARAzURnmiJ31WTS1";
+  };
+
+  programs = {
+    adb.enable = true;
+    fish.enable = true;
+    light.enable = true;
+    mosh.enable = true;
+    ssh.startAgent = true;
+
+    # Required by impermanence
+    fuse.userAllowOther = true;
+  };
+
+  environment.systemPackages =
+    # programs from the depot
+    (with depot; [
+      screenLock
+      tools.nsfv-setup
+      users.tazjin.emacs
+      third_party.agenix.cli
+    ]) ++
+
+    # programs from nixpkgs
+    (with pkgs; [
+      amber
+      audacity
+      bat
+      curl
+      ddcutil
+      direnv
+      dmd
+      dnsutils
+      emacsGcc # emacsclient
+      exa
+      fd
+      file
+      firefox
+      fractal
+      gdb
+      gh
+      git
+      gnupg
+      google-chrome
+      gtk3 # for gtk-launch
+      htop
+      hyperfine
+      iftop
+      imagemagick
+      jq
+      lieer
+      man-pages
+      mosh
+      msmtp
+      mullvad-vpn
+      networkmanagerapplet
+      nix-prefetch-github
+      nmap
+      notmuch
+      openssh
+      openssl
+      paperlike-go
+      pass
+      pavucontrol
+      pinentry
+      pinentry-emacs
+      pulseaudio # for pactl
+      pwgen
+      quasselClient
+      rink
+      ripgrep
+      rustup
+      screen
+      scrot
+      tig
+      tokei
+      tree
+      unzip
+      vlc
+      whois
+      xsecurelock
+      zoxide
+    ]);
+
+  systemd.user.services.lieer-tazjin = {
+    description = "Synchronise mail@tazj.in via lieer";
+    script = "${pkgs.lieer}/bin/gmi sync";
+
+    serviceConfig = {
+      WorkingDirectory = "%h/mail/account.tazjin";
+      Type = "oneshot";
+    };
+  };
+
+  systemd.user.timers.lieer-tazjin = {
+    wantedBy = [ "timers.target" ];
+
+    timerConfig = {
+      OnActiveSec = "1";
+      OnUnitActiveSec = "180";
+    };
+  };
+
+  home-manager.useGlobalPkgs = true;
+  home-manager.users.tazjin = { config, lib, ... }: {
+    imports = [ "${depot.third_party.impermanence}/home-manager.nix" ];
+
+    home.persistence."/persist/tazjin/home" = {
+      allowOther = true;
+
+      directories = [
+        ".cargo"
+        ".config/audacity"
+        ".config/google-chrome"
+        ".config/quassel-irc.org"
+        ".config/spotify"
+        ".config/syncthing"
+        ".elfeed"
+        ".gnupg"
+        ".local/share/Steam"
+        ".local/share/audacity"
+        ".local/share/direnv"
+        ".local/share/fish"
+        ".local/share/keyrings"
+        ".local/share/zoxide"
+        ".mozilla/firefox"
+        ".password-store"
+        ".rustup"
+        ".ssh"
+        ".steam"
+        ".telega"
+        "go"
+        "mail"
+      ];
+
+      files = [
+        ".notmuch-config"
+      ];
+    };
+
+    home.activation.screenshots = lib.hm.dag.entryAnywhere ''
+      $DRY_RUN_CMD mkdir -p $HOME/screenshots
+    '';
+
+    programs.git = {
+      enable = true;
+      userName = "Vincent Ambo";
+      userEmail = "mail@tazj.in";
+      extraConfig = {
+        pull.rebase = true;
+        init.defaultBranch = "canon";
+      };
+    };
+
+    programs.fish = {
+      enable = true;
+      interactiveShellInit = ''
+        ${pkgs.zoxide}/bin/zoxide init fish | source
+      '';
+    };
+
+    services.screen-locker = {
+      enable = true;
+      enableDetectSleep = true;
+      inactiveInterval = 10; # minutes
+      lockCmd = "${screenLock}/bin/tazjin-screen-lock";
+    };
+
+    services.picom = {
+      enable = true;
+      vSync = true;
+      backend = "glx";
+    };
+
+    # Enable the dunst notification daemon, but force the
+    # configuration file separately instead of going via the strange
+    # Nix->dunstrc encoding route.
+    services.dunst.enable = true;
+    xdg.configFile."dunst/dunstrc" = {
+      source = depot.users.tazjin.dotfiles.dunstrc;
+      onChange = ''
+        ${pkgs.procps}/bin/pkill -u "$USER" ''${VERBOSE+-e} dunst || true
+      '';
+    };
+
+    systemd.user.startServices = true;
+  };
+
+  services.tailscale.enable = true;
+
+  services.zerotierone.enable = true;
+  services.zerotierone.joinNetworks = [
+    "35c192ce9bd4c8c7"
+  ];
+
+  system.stateVersion = "20.09";
+})