diff --git a/default.nix b/default.nix
index b5c4799..5ebb391 100644
--- a/default.nix
+++ b/default.nix
@@ -452,6 +452,14 @@ in
       '';
     };
 
+    sieveDirectory = mkOption {
+      type = types.path;
+      default = "/var/sieve";
+      description = ''
+        Where to store the sieve scripts.
+      '';
+    };
+
     virusScanning = mkOption {
       type = types.bool;
       default = false;
diff --git a/mail-server/dovecot.nix b/mail-server/dovecot.nix
index 4e77baf..23609fe 100644
--- a/mail-server/dovecot.nix
+++ b/mail-server/dovecot.nix
@@ -217,8 +217,8 @@ in
 
         plugin {
           sieve_plugins = sieve_imapsieve sieve_extprograms
-          sieve = file:/var/sieve/%u/scripts;active=/var/sieve/%u/active.sieve
-          sieve_default = file:/var/sieve/%u/default.sieve
+          sieve = file:${cfg.sieveDirectory}/%u/scripts;active=${cfg.sieveDirectory}/%u/active.sieve
+          sieve_default = file:${cfg.sieveDirectory}/%u/default.sieve
           sieve_default_name = default
 
           # From elsewhere to Spam folder
diff --git a/mail-server/users.nix b/mail-server/users.nix
index 3ab31d5..0b168c1 100644
--- a/mail-server/users.nix
+++ b/mail-server/users.nix
@@ -35,31 +35,31 @@ let
     set -euo pipefail
 
     # Create directory to store user sieve scripts if it doesn't exist
-    if (! test -d "/var/sieve"); then
-      mkdir "/var/sieve"
-      chown "${vmailUserName}:${vmailGroupName}" "/var/sieve"
-      chmod 770 "/var/sieve"
+    if (! test -d "${sieveDirectory}"); then
+      mkdir "${sieveDirectory}"
+      chown "${vmailUserName}:${vmailGroupName}" "${sieveDirectory}"
+      chmod 770 "${sieveDirectory}"
     fi
 
     # Copy user's sieve script to the correct location (if it exists).  If it
     # is null, remove the file.
     ${lib.concatMapStringsSep "\n" ({ name, sieveScript }:
       if lib.isString sieveScript then ''
-        if (! test -d "/var/sieve/${name}"); then
-          mkdir -p "/var/sieve/${name}"
-          chown "${vmailUserName}:${vmailGroupName}" "/var/sieve/${name}"
-          chmod 770 "/var/sieve/${name}"
+        if (! test -d "${sieveDirectory}/${name}"); then
+          mkdir -p "${sieveDirectory}/${name}"
+          chown "${vmailUserName}:${vmailGroupName}" "${sieveDirectory}/${name}"
+          chmod 770 "${sieveDirectory}/${name}"
         fi
-        cat << 'EOF' > "/var/sieve/${name}/default.sieve"
+        cat << 'EOF' > "${sieveDirectory}/${name}/default.sieve"
         ${sieveScript}
         EOF
-        chown "${vmailUserName}:${vmailGroupName}" "/var/sieve/${name}/default.sieve"
+        chown "${vmailUserName}:${vmailGroupName}" "${sieveDirectory}/${name}/default.sieve"
       '' else ''
-        if (test -f "/var/sieve/${name}/default.sieve"); then
-          rm "/var/sieve/${name}/default.sieve"
+        if (test -f "${sieveDirectory}/${name}/default.sieve"); then
+          rm "${sieveDirectory}/${name}/default.sieve"
         fi
-        if (test -f "/var/sieve/${name}.svbin"); then
-          rm "/var/sieve/${name}/default.svbin"
+        if (test -f "${sieveDirectory}/${name}.svbin"); then
+          rm "${sieveDirectory}/${name}/default.svbin"
         fi
       '') (map (user: { inherit (user) name sieveScript; })
             (lib.attrValues loginAccounts))}