diff --git a/modules/nixos/options.nix b/modules/nixos/options.nix
index 1e4c63f..45932c0 100644
--- a/modules/nixos/options.nix
+++ b/modules/nixos/options.nix
@@ -142,6 +142,7 @@
       anubis.enable = lib.mkEnableOption "anubis";
       syncthing.enable = lib.mkEnableOption "syncthing";
       jellyfin.enable = lib.mkEnableOption "jellyfin";
+      mailserver.enable = lib.mkEnableOption "mailserver";
       vaultwarden.enable = lib.mkEnableOption "vaultwarden";
       nginx.enable = lib.mkEnableOption "nginx";
       ollama.enable = lib.mkEnableOption "ollama";
diff --git a/modules/nixos/services/default.nix b/modules/nixos/services/default.nix
index ee6d2db..bf63669 100644
--- a/modules/nixos/services/default.nix
+++ b/modules/nixos/services/default.nix
@@ -10,6 +10,7 @@
     ./glance.nix
     ./hydra.nix
     ./jellyfin.nix
+    ./mailserver.nix
     ./nginx.nix
     ./syncthing.nix
     ./tailscale.nix
diff --git a/modules/nixos/services/mailserver.nix b/modules/nixos/services/mailserver.nix
new file mode 100644
index 0000000..6d38dd7
--- /dev/null
+++ b/modules/nixos/services/mailserver.nix
@@ -0,0 +1,30 @@
+{ config, inputs, lib, ... }:
+{
+  imports = [
+    inputs.simple-nixos-mailserver.nixosModule
+  ];
+
+  config = lib.mkMerge [
+    (lib.optionalAttrs config.osbmModules.services.mailserver.enable {
+      mailserver = {
+        enable = true;
+        stateVersion = 3;
+        fqdn = "mail.osbm.dev";
+        domains = [ "osbm.dev" ];
+
+        # A list of all login accounts. To create the password hashes, use
+        # nix-shell -p mkpasswd --run 'mkpasswd -sm bcrypt'
+        loginAccounts = {
+          "osbm@osbm.dev" = {
+            hashedPasswordFile = "/persist/osbm.passwd"; # TODO: Make this into agenix secret
+            aliases = ["postmaster@osbm.dev"];
+          };
+        };
+
+        # Use Let's Encrypt certificates. Note that this needs to set up a stripped
+        # down nginx and opens port 80.
+        certificateScheme = "acme-nginx";
+      };
+    })
+  ];
+}
\ No newline at end of file