diff --git a/fediversity/default.nix b/fediversity/default.nix
new file mode 100644
index 0000000..46ee05d
--- /dev/null
+++ b/fediversity/default.nix
@@ -0,0 +1,103 @@
+{ lib, config, ... }:
+
+let
+  inherit (builtins) toString;
+  inherit (lib) mkOption mkEnableOption;
+  inherit (lib.types) types;
+
+in {
+  imports = [
+    ./garage.nix
+    ./mastodon.nix
+    ./pixelfed.nix
+    ./peertube.nix
+  ];
+
+  options = {
+    fediversity = {
+      enable = mkEnableOption "the collection of services bundled under Fediversity";
+
+      domain = mkOption {
+        type = types.str;
+        description = ''
+          root domain for the Fediversity services
+
+          For instance, if this option is set to `foo.example.com`, then
+          Pixelfed might be under `pixelfed.foo.example.com`.
+        '';
+      };
+
+      mastodon.enable = mkEnableOption "default Fediversity Mastodon configuration";
+      pixelfed.enable = mkEnableOption "default Fediversity Pixelfed configuration";
+      peertube.enable = mkEnableOption "default Fediversity PeerTube configuration";
+
+      internal = mkOption {
+        description = "options that are only meant to be used internally; change at your own risk";
+        default = {};
+        type = types.submodule {
+          options = {
+            garage = {
+              api = {
+                domain = mkOption {
+                  type = types.str;
+                  default = "s3.garage.${config.fediversity.domain}";
+                };
+                port = mkOption {
+                  type = types.int;
+                  default = 3900;
+                };
+                url = mkOption {
+                  type = types.str;
+                  default = "http://${config.fediversity.internal.garage.api.domain}:${toString config.fediversity.internal.garage.api.port}";
+                };
+              };
+
+              rpc = {
+                port = mkOption {
+                  type = types.int;
+                  default = 3901;
+                };
+              };
+
+              web = {
+                rootDomain = mkOption {
+                  type = types.str;
+                  default = "web.garage.${config.fediversity.domain}";
+                };
+                port = mkOption {
+                  type = types.int;
+                  default = 3902;
+                };
+                rootDomainAndPort = mkOption {
+                  type = types.str;
+                  default = "${config.fediversity.internal.garage.web.rootDomain}:${toString config.fediversity.internal.garage.web.port}";
+                };
+                urlFor = mkOption {
+                  type = types.functionTo types.str;
+                  default = bucket: "http://${bucket}.${config.fediversity.internal.garage.web.rootDomainAndPort}";
+                };
+              };
+            };
+
+            ## REVIEW: Do we want to recreate options under
+            ## `fediversity.internal` or would we rather use the options from
+            ## the respective services? See Taeer's comment:
+            ## https://git.fediversity.eu/taeer/simple-nixos-fediverse/pulls/22#issuecomment-124
+            pixelfed.domain = mkOption {
+              type = types.str;
+              default = "pixelfed.${config.fediversity.domain}";
+            };
+            mastodon.domain = mkOption {
+              type = types.str;
+              default = "mastdodon.${config.fediversity.domain}";
+            };
+            peertube.domain = mkOption {
+              type = types.str;
+              default = "peertube.${config.fediversity.domain}";
+            };
+          };
+        };
+      };
+    };
+  };
+}
diff --git a/garage.nix b/fediversity/garage.nix
similarity index 83%
rename from garage.nix
rename to fediversity/garage.nix
index b58738d..84af662 100644
--- a/garage.nix
+++ b/fediversity/garage.nix
@@ -6,9 +6,12 @@ let
     secret = "82b2b4cbef27bf8917b350d5b10a87c92fa9c8b13a415aeeea49726cf335d74e";
   };
 in
+
 # TODO: expand to a multi-machine setup
-{ config, lib, pkgs, ... }: 
+{ config, lib, pkgs, ... }:
+
 let
+  inherit (builtins) toString;
   inherit (lib) types mkOption mkEnableOption optionalString concatStringsSep;
   inherit (lib.strings) escapeShellArg;
   cfg = config.services.garage;
@@ -39,7 +42,7 @@ let
       ${optionalString corsRules.enable ''
         garage bucket allow --read --write --owner ${bucketArg} --key tmp
         # TODO: endpoin-url should not be hard-coded
-        aws --region ${cfg.settings.s3_api.s3_region} --endpoint-url http://s3.garage.localhost:3900 s3api put-bucket-cors --bucket ${bucketArg} --cors-configuration ${corsRulesJSON}
+        aws --region ${cfg.settings.s3_api.s3_region} --endpoint-url ${config.fediversity.internal.garage.api.url} s3api put-bucket-cors --bucket ${bucketArg} --cors-configuration ${corsRulesJSON}
         garage bucket deny --read --write --owner ${bucketArg} --key tmp
       ''}
     '';
@@ -53,7 +56,9 @@ let
     ${concatMapAttrs (ensureAccessScriptFn key) ensureAccess}
   '';
   ensureKeysScript = concatMapAttrs ensureKeyScriptFn cfg.ensureKeys;
-in {
+in
+
+{
   # add in options to ensure creation of buckets and keys
   options = {
     services.garage = {
@@ -126,24 +131,27 @@ in {
     };
   };
 
-  config = {
+  config = lib.mkIf config.fediversity.enable {
     virtualisation.diskSize = 2048;
     virtualisation.forwardPorts = [
       {
         from = "host";
-        host.port = 3901;
-        guest.port = 3901;
+        host.port = config.fediversity.internal.garage.rpc.port;
+        guest.port = config.fediversity.internal.garage.rpc.port;
       }
       {
         from = "host";
-        host.port = 3902;
-        guest.port = 3902;
+        host.port = config.fediversity.internal.garage.web.port;
+        guest.port = config.fediversity.internal.garage.web.port;
       }
     ];
 
     environment.systemPackages = [ pkgs.minio-client pkgs.awscli ];
 
-    networking.firewall.allowedTCPPorts = [ 3901 3902 ];
+    networking.firewall.allowedTCPPorts = [
+      config.fediversity.internal.garage.rpc.port
+      config.fediversity.internal.garage.web.port
+    ];
     services.garage = {
       enable = true;
       package = pkgs.garage_0_9;
@@ -152,15 +160,15 @@ in {
         # TODO: use a secret file
         rpc_secret = "d576c4478cc7d0d94cfc127138cbb82018b0155c037d1c827dfb6c36be5f6625";
         # TODO: why does this have to be set? is there not a sensible default?
-        rpc_bind_addr = "[::]:3901";
-        rpc_public_addr = "[::1]:3901";
-        s3_api.api_bind_addr = "[::]:3900";
-        s3_web.bind_addr = "[::]:3902";
-        s3_web.root_domain = ".web.garage.localhost";
+        rpc_bind_addr = "[::]:${toString config.fediversity.internal.garage.rpc.port}";
+        rpc_public_addr = "[::1]:${toString config.fediversity.internal.garage.rpc.port}";
+        s3_api.api_bind_addr = "[::]:${toString config.fediversity.internal.garage.api.port}";
+        s3_web.bind_addr = "[::]:${toString config.fediversity.internal.garage.web.port}";
+        s3_web.root_domain = ".${config.fediversity.internal.garage.web.rootDomain}";
         index = "index.html";
 
         s3_api.s3_region = "garage";
-        s3_api.root_domain = ".s3.garage.localhost";
+        s3_api.root_domain = ".${config.fediversity.internal.garage.api.domain}";
       };
     };
     systemd.services.ensure-garage = {
@@ -173,9 +181,9 @@ in {
       script = ''
         set -xeuo pipefail
 
-        # Give garage time to start up by waiting until somethings speaks HTTP
-        # behind localhost:3900.
-        until curl -sio /dev/null http://localhost:3900/; do sleep 1; done
+        # Give Garage time to start up by waiting until somethings speaks HTTP
+        # behind Garage's API URL.
+        until ${pkgs.curl}/bin/curl -sio /dev/null ${config.fediversity.internal.garage.api.url}; do sleep 1; done
 
         # XXX: this is very sensitive to being a single instance
         # (doing the bare minimum to get garage up and running)
diff --git a/mastodon.nix b/fediversity/mastodon.nix
similarity index 81%
rename from mastodon.nix
rename to fediversity/mastodon.nix
index e0c2ea4..62599b5 100644
--- a/mastodon.nix
+++ b/fediversity/mastodon.nix
@@ -4,7 +4,10 @@ let
     secret = "7d37d093435a41f2aab8f13c19ba067d9776c90215f56614adad6ece597dbb34";
   };
 in
-{ config, lib, pkgs, ... }: {
+
+{ config, lib, pkgs, ... }:
+
+lib.mkIf (config.fediversity.enable && config.fediversity.mastodon.enable) {
  #### garage setup
   services.garage = {
     ensureBuckets = {
@@ -35,7 +38,7 @@ in
     extraConfig = rec {
       S3_ENABLED = "true";
       # TODO: this shouldn't be hard-coded, it should come from the garage configuration
-      S3_ENDPOINT = "http://s3.garage.localhost:3900";
+      S3_ENDPOINT = config.fediversity.internal.garage.api.url;
       S3_REGION = "garage";
       S3_BUCKET = "mastodon";
       # use <S3_BUCKET>.<S3_ENDPOINT>
@@ -43,7 +46,7 @@ in
       AWS_ACCESS_KEY_ID = snakeoil_key.id;
       AWS_SECRET_ACCESS_KEY = snakeoil_key.secret;
       S3_PROTOCOL = "http";
-      S3_HOSTNAME = "web.garage.localhost:3902";
+      S3_HOSTNAME = config.fediversity.internal.garage.web.rootDomainAndPort;
       # by default it tries to use "<S3_HOSTNAME>/<S3_BUCKET>"
       S3_ALIAS_HOST = "${S3_BUCKET}.${S3_HOSTNAME}";
       # SEE: the last section in https://docs.joinmastodon.org/admin/optional/object-storage/
@@ -60,12 +63,14 @@ in
   services.mastodon = {
     enable = true;
 
-    # TODO: set up a domain name, and a DNS service so that this can run not in a vm
-    # localDomain = "domain.social";
+    localDomain = config.fediversity.internal.mastodon.domain;
     configureNginx = true;
 
     # TODO: configure a mailserver so this works
-    # smtp.fromAddress = "mastodon@domain.social";
+    smtp = {
+      fromAddress = "noreply@${config.fediversity.internal.mastodon.domain}";
+      createLocally = false;
+    };
 
     # TODO: this is hardware-dependent. let's figure it out when we have hardware
     # streamingProcesses = 1;
@@ -78,4 +83,3 @@ in
     # defaults.email = "test@example.com";
   };
 }
-
diff --git a/peertube.nix b/fediversity/peertube.nix
similarity index 72%
rename from peertube.nix
rename to fediversity/peertube.nix
index e0d4926..88d26e1 100644
--- a/peertube.nix
+++ b/fediversity/peertube.nix
@@ -4,7 +4,10 @@ let
     secret = "7295c4201966a02c2c3d25b5cea4a5ff782966a2415e3a196f91924631191395";
   };
 in
-{ config, lib, pkgs, ... }: {
+
+{ config, lib, pkgs, ... }:
+
+lib.mkIf (config.fediversity.enable && config.fediversity.peertube.enable) {
   networking.firewall.allowedTCPPorts = [ 80 9000 ];
 
   services.garage = {
@@ -50,30 +53,38 @@ in
   };
 
   services.peertube = {
+    enable = true;
+    localDomain = config.fediversity.internal.peertube.domain;
+
+    # TODO: in most of nixpkgs, these are true by default. upstream that unless there's a good reason not to.
+    redis.createLocally = true;
+    database.createLocally = true;
+    configureNginx = true;
+
     settings = {
       object_storage = {
         enabled = true;
-        endpoint = "http://s3.garage.localhost:3900";
+        endpoint = config.fediversity.internal.garage.api.url;
         region = "garage";
 
         # not supported by garage 
         # SEE: https://garagehq.deuxfleurs.fr/documentation/connect/apps/#peertube
         proxy.proxyify_private_files = false;
 
-        web_videos = {
+        web_videos = rec {
           bucket_name = "peertube-videos";
           prefix = "";
-          base_url = "http://peertube-videos.web.garage.localhost:3902";
+          base_url = config.fediversity.internal.garage.web.urlFor bucket_name;
         };
-        videos = {
+        videos = rec {
           bucket_name = "peertube-videos";
           prefix = "";
-          base_url = "http://peertube-videos.web.garage.localhost:3902";
+          base_url = config.fediversity.internal.garage.web.urlFor bucket_name;
         };
-        streaming_playlists = {
+        streaming_playlists = rec {
           bucket_name = "peertube-playlists";
           prefix = "";
-          base_url = "http://peertube-playlists.web.garage.localhost:3902";
+          base_url = config.fediversity.internal.garage.web.urlFor bucket_name;
         };
       };
     };
diff --git a/pixelfed-group-permissions.patch b/fediversity/pixelfed-group-permissions.patch
similarity index 100%
rename from pixelfed-group-permissions.patch
rename to fediversity/pixelfed-group-permissions.patch
diff --git a/pixelfed.nix b/fediversity/pixelfed.nix
similarity index 81%
rename from pixelfed.nix
rename to fediversity/pixelfed.nix
index 9d2281f..1edc914 100644
--- a/pixelfed.nix
+++ b/fediversity/pixelfed.nix
@@ -4,7 +4,10 @@ let
     secret = "5be6799a88ca9b9d813d1a806b64f15efa49482dbe15339ddfaf7f19cf434987";
   };
 in
-{ config, lib, pkgs, ... }: {
+
+{ config, lib, pkgs, ... }:
+
+lib.mkIf (config.fediversity.enable && config.fediversity.pixelfed.enable) {
   services.garage = {
     ensureBuckets = {
       pixelfed = {
@@ -32,9 +35,11 @@ in
     };
   };
 
-  services.pixelfed.enable = true;
+  services.pixelfed = {
+    enable = true;
+    domain = config.fediversity.internal.pixelfed.domain;
+  };
 
-  # TODO: factor these out so we're only defining e.g. s3.garage.localhost and port 3900 in one place
   services.pixelfed.settings = {
     # DANGEROUSLY_SET_FILESYSTEM_DRIVER = "s3";
     FILESYSTEM_CLOUD = "s3";
@@ -42,9 +47,9 @@ in
     AWS_ACCESS_KEY_ID = snakeoil_key.id;
     AWS_SECRET_ACCESS_KEY = snakeoil_key.secret;
     AWS_DEFAULT_REGION = "garage";
-    AWS_URL = "http://pixelfed.web.garage.localhost:3902/";
+    AWS_URL = config.fediversity.internal.garage.web.urlFor "pixelfed";
     AWS_BUCKET = "pixelfed";
-    AWS_ENDPOINT = "http://s3.garage.localhost:3900";
+    AWS_ENDPOINT = config.fediversity.internal.garage.api.url;
     AWS_USE_PATH_STYLE_ENDPOINT = false;
   };
 
diff --git a/flake.nix b/flake.nix
index aeb7dba..737ad31 100644
--- a/flake.nix
+++ b/flake.nix
@@ -5,47 +5,47 @@
     nixpkgs.url = "github:radvendii/nixpkgs/nixos_rebuild_tests";
   };
 
-  outputs = { self, nixpkgs }: 
+  outputs = { self, nixpkgs }:
   let
     system = "x86_64-linux";
     pkgs = nixpkgs.legacyPackages.${system};
   in {
 
     nixosModules = {
-      interactive-vm = import ./interactive-vm.nix;
-      mastodon = import ./mastodon.nix;
-      mastodon-vm = import ./mastodon-vm.nix;
-      peertube = import ./peertube.nix;
-      peertube-vm = import ./peertube-vm.nix;
-      pixelfed = import ./pixelfed.nix;
-      pixelfed-vm = import ./pixelfed-vm.nix;
-      garage = import ./garage.nix;
+      ## Fediversity modules
+      fediversity = import ./fediversity;
+
+      ## VM-specific modules
+      interactive-vm = import ./vm/interactive-vm.nix;
+      mastodon-vm = import ./vm/mastodon-vm.nix;
+      peertube-vm = import ./vm/peertube-vm.nix;
+      pixelfed-vm = import ./vm/pixelfed-vm.nix;
     };
 
     nixosConfigurations = {
       mastodon = nixpkgs.lib.nixosSystem {
         inherit system;
-        modules = with self.nixosModules; [ interactive-vm mastodon mastodon-vm garage ];
+        modules = with self.nixosModules; [ fediversity interactive-vm mastodon-vm ];
       };
 
       peertube = nixpkgs.lib.nixosSystem {
         inherit system;
-        modules = with self.nixosModules; [ interactive-vm peertube peertube-vm garage ];
+        modules = with self.nixosModules; [ fediversity interactive-vm peertube-vm ];
       };
 
       pixelfed = nixpkgs.lib.nixosSystem {
         inherit system;
-        modules = with self.nixosModules; [ interactive-vm pixelfed pixelfed-vm garage ];
+        modules = with self.nixosModules; [ fediversity interactive-vm pixelfed-vm ];
       };
 
       all = nixpkgs.lib.nixosSystem {
         inherit system;
         modules = with self.nixosModules; [
+          fediversity
           interactive-vm
-          peertube peertube-vm
-          pixelfed pixelfed-vm
-          mastodon mastodon-vm
-          garage
+          peertube-vm
+          pixelfed-vm
+          mastodon-vm
         ];
       };
     };
diff --git a/tests/mastodon-garage.nix b/tests/mastodon-garage.nix
index d20c5ad..672b70f 100644
--- a/tests/mastodon-garage.nix
+++ b/tests/mastodon-garage.nix
@@ -37,7 +37,7 @@ pkgs.nixosTest {
   nodes = {
     server = { config, ... }: {
       virtualisation.memorySize = lib.mkVMOverride 4096;
-      imports = with self.nixosModules; [ garage mastodon mastodon-vm ];
+      imports = with self.nixosModules; [ mastodon-vm ];
       # TODO: pair down
       environment.systemPackages = with pkgs; [
         python3
@@ -57,7 +57,7 @@ pkgs.nixosTest {
     };
   };
 
-  testScript = ''
+  testScript = { nodes, ... }: ''
     import re
     import time
 
@@ -95,7 +95,7 @@ pkgs.nixosTest {
       server.succeed("toot post --media $POST_MEDIA")
 
     with subtest("access garage"):
-      server.succeed("mc alias set garage http://s3.garage.localhost:3900 --api s3v4 --path off $AWS_ACCESS_KEY_ID $AWS_SECRET_ACCESS_KEY")
+      server.succeed("mc alias set garage ${nodes.server.fediversity.internal.garage.api.url} --api s3v4 --path off $AWS_ACCESS_KEY_ID $AWS_SECRET_ACCESS_KEY")
       server.succeed("mc ls garage/mastodon")
 
     with subtest("access image in garage"):
@@ -121,6 +121,7 @@ pkgs.nixosTest {
         raise Exception("mastodon did not send a content security policy header")
       csp = csp_match.group(1)
       # the img-src content security policy should include the garage server
+      ## TODO: use `nodes.server.fediversity.internal.garage.api.url` same as above, but beware of escaping the regex.
       garage_csp = re.match(".*; img-src[^;]*web\.garage\.localhost:3902.*", csp)
       if garage_csp is None:
         raise Exception("Mastodon's content security policy does not include garage server. image will not be displayed properly on mastodon.")
diff --git a/tests/pixelfed-garage.nix b/tests/pixelfed-garage.nix
index e084cb0..b25bc66 100644
--- a/tests/pixelfed-garage.nix
+++ b/tests/pixelfed-garage.nix
@@ -29,15 +29,16 @@ let
     print("Open login page...", file=sys.stderr)
     driver.get("http://pixelfed.localhost/login")
     print("Enter email...", file=sys.stderr)
-    driver.find_element(By.ID, "email").send_keys(${email})
+    driver.find_element(By.ID, "email").send_keys("${email}")
     print("Enter password...", file=sys.stderr)
-    driver.find_element(By.ID, "password").send_keys(${password})
+    driver.find_element(By.ID, "password").send_keys("${password}")
     # FIXME: This is disgusting. Find instead the input type submit in the form
     # with action ending in "/login".
     print("Click “Login” button...", file=sys.stderr)
     driver.find_element(By.XPATH, "//button[normalize-space()='Login']").click()
   '';
 
+  ## NOTE: `path` must be a valid python string, either a variable or _quoted_.
   seleniumTakeScreenshot = path: ''
     print("Take screenshot...", file=sys.stderr)
     if not driver.save_screenshot(${path}):
@@ -135,11 +136,7 @@ pkgs.nixosTest {
         memorySize = lib.mkVMOverride 8192;
         cores = 8;
       };
-      imports = with self.nixosModules; [
-        garage
-        pixelfed
-        pixelfed-vm
-      ];
+      imports = with self.nixosModules; [ pixelfed-vm ];
       # TODO: pair down
       environment.systemPackages = with pkgs; [
         python3
@@ -163,7 +160,7 @@ pkgs.nixosTest {
     };
   };
 
-  testScript = ''
+  testScript = { nodes, ... }: ''
     import re
 
     server.start()
@@ -172,7 +169,7 @@ pkgs.nixosTest {
       server.wait_for_unit("phpfpm-pixelfed.service")
 
     with subtest("Account creation"):
-      server.succeed(f"pixelfed-manage user:create --name=test --username=test --email=${email} --password=${password} --confirm_email=1")
+      server.succeed("pixelfed-manage user:create --name=test --username=test --email=${email} --password=${password} --confirm_email=1")
 
     # NOTE: This could in theory give a false positive if pixelfed changes it's
     # colorscheme to include pure green. (see same problem in pixelfed-garage.nix).
@@ -180,7 +177,7 @@ pkgs.nixosTest {
     # there, then post a green image and check that the green pixel IS there.
 
     with subtest("Image displays"):
-      server.succeed(f"su - selenium -c 'selenium-script-post-picture ${email} ${password}'")
+      server.succeed("su - selenium -c 'selenium-script-post-picture ${email} ${password}'")
       server.copy_from_vm("/home/selenium/screenshot.png", "")
       displayed_colors = server.succeed("magick /home/selenium/screenshot.png -define histogram:unique-colors=true -format %c histogram:info:")
       # check that the green image displayed somewhere
@@ -189,14 +186,14 @@ pkgs.nixosTest {
         raise Exception("cannot detect the uploaded image on pixelfed page.")
 
     with subtest("access garage"):
-      server.succeed("mc alias set garage http://s3.garage.localhost:3900 --api s3v4 --path off $AWS_ACCESS_KEY_ID $AWS_SECRET_ACCESS_KEY")
+      server.succeed("mc alias set garage ${nodes.server.fediversity.internal.garage.api.url} --api s3v4 --path off $AWS_ACCESS_KEY_ID $AWS_SECRET_ACCESS_KEY")
       server.succeed("mc ls garage/pixelfed")
 
     with subtest("access image in garage"):
-      image = server.succeed("mc find garage --regex '\.png' --ignore '*_thumb.png'")
+      image = server.succeed("mc find garage --regex '\\.png' --ignore '*_thumb.png'")
       image = image.rstrip()
       if image == "":
-        raise Exception("image posted to mastodon did not get stored in garage")
+        raise Exception("image posted to Pixelfed did not get stored in garage")
       server.succeed(f"mc cat {image} >/garage-image.png")
       garage_image_hash = server.succeed("identify -quiet -format '%#' /garage-image.png")
       image_hash = server.succeed("identify -quiet -format '%#' $POST_MEDIA")
@@ -204,8 +201,8 @@ pkgs.nixosTest {
         raise Exception("image stored in garage did not match image uploaded")
 
     with subtest("Check that image comes from garage"):
-      src = server.succeed(f"su - selenium -c 'selenium-script-get-src ${email} ${password}'")
-      if not src.startswith("http://pixelfed.web.garage.localhost:3902/"):
+      src = server.succeed("su - selenium -c 'selenium-script-get-src ${email} ${password}'")
+      if not src.startswith("${nodes.server.fediversity.internal.garage.web.urlFor "pixelfed"}"):
         raise Exception("image does not come from garage")
   '';
 }
diff --git a/interactive-vm.nix b/vm/interactive-vm.nix
similarity index 100%
rename from interactive-vm.nix
rename to vm/interactive-vm.nix
diff --git a/mastodon-vm.nix b/vm/mastodon-vm.nix
similarity index 91%
rename from mastodon-vm.nix
rename to vm/mastodon-vm.nix
index fcfe3e5..ea17f27 100644
--- a/mastodon-vm.nix
+++ b/vm/mastodon-vm.nix
@@ -1,18 +1,19 @@
 { modulesPath, lib, config, ... }: {
 
-  imports = [ (modulesPath + "/virtualisation/qemu-vm.nix") ];
+  imports = [
+    ../fediversity
+    (modulesPath + "/virtualisation/qemu-vm.nix")
+  ];
 
   config = lib.mkMerge [
     {
+      fediversity = {
+        enable = true;
+        domain = "localhost";
+        mastodon.enable = true;
+      };
+
       services.mastodon = {
-        # redirects to localhost, but allows it to have a proper domain name
-        localDomain = "mastodon.localhost";
-
-        smtp = {
-          fromAddress = "mastodon@mastodon.localhost";
-          createLocally = false;
-        };
-
         extraConfig = {
           EMAIL_DOMAIN_ALLOWLIST = "example.com";
         };
@@ -56,7 +57,7 @@
           BIND = "0.0.0.0";
           # for letter_opener (still doesn't work though)
           REMOTE_DEV = "true";
-          LOCAL_DOMAIN = "mastodon.localhost:8443";
+          LOCAL_DOMAIN = "${config.fediversity.internal.mastodon.domain}:8443";
         };
       };
 
diff --git a/peertube-vm.nix b/vm/peertube-vm.nix
similarity index 53%
rename from peertube-vm.nix
rename to vm/peertube-vm.nix
index d38a625..5f40f4f 100644
--- a/peertube-vm.nix
+++ b/vm/peertube-vm.nix
@@ -1,9 +1,11 @@
 { pkgs, modulesPath, ... }: {
-  imports = [ (modulesPath + "/virtualisation/qemu-vm.nix") ];
+
+  imports = [
+    ../fediversity
+    (modulesPath + "/virtualisation/qemu-vm.nix")
+  ];
+
   services.peertube = {
-    enable = true;
-    # redirects to localhost, but allows it to have a proper domain name
-    localDomain = "peertube.localhost";
     enableWebHttps = false;
     settings = {
       listen.hostname = "0.0.0.0";
@@ -13,11 +15,6 @@
     secrets.secretsFile = pkgs.writeText "secret" ''
       574e093907d1157ac0f8e760a6deb1035402003af5763135bae9cbd6abe32b24
     '';
-
-    # TODO: in most of nixpkgs, these are true by default. upstream that unless there's a good reason not to.
-    redis.createLocally = true;
-    database.createLocally = true;
-    configureNginx = true;
   };
 
   virtualisation.forwardPorts = [
diff --git a/pixelfed-vm.nix b/vm/pixelfed-vm.nix
similarity index 70%
rename from pixelfed-vm.nix
rename to vm/pixelfed-vm.nix
index 451aeda..8f97180 100644
--- a/pixelfed-vm.nix
+++ b/vm/pixelfed-vm.nix
@@ -1,8 +1,18 @@
 { pkgs, modulesPath, ... }: {
-  imports = [ (modulesPath + "/virtualisation/qemu-vm.nix") ];
+
+  imports = [
+    ../fediversity
+    (modulesPath + "/virtualisation/qemu-vm.nix")
+  ];
+
+  fediversity = {
+    enable = true;
+    domain = "localhost";
+    pixelfed.enable = true;
+  };
+
   networking.firewall.allowedTCPPorts = [ 80 ];
   services.pixelfed = {
-    domain = "pixelfed.localhost";
     # TODO: secrets management!
     secretFile = pkgs.writeText "secrets.env" ''
       APP_KEY=adKK9EcY8Hcj3PLU7rzG9rJ6KKTOtYfA
@@ -14,7 +24,7 @@
     # I feel like this should have an `enable` option and be configured via `services.nginx` rather than mirroring those options in services.pixelfed.nginx
     # TODO: If that indeed makes sense, upstream it.
     nginx = {
-      # locations."/public/".proxyPass = "http://pixelfed.web.garage.localhost:3902/public/";
+      # locations."/public/".proxyPass = "${config.fediversity.internal.garage.web.urlFor "pixelfed"}/public/";
     };
   };
   virtualisation.memorySize = 2048;