From 190886c5cca51bee671c5f3329ce03e119768029 Mon Sep 17 00:00:00 2001
From: Maximilian Bosch <maximilian@mbosch.me>
Date: Mon, 31 Jul 2023 18:54:17 +0200
Subject: [PATCH] nixos/matrix-synapse: clarify that `extras` are additive

---
 nixos/modules/services/matrix/synapse.nix | 4 ++++
 pkgs/servers/matrix-synapse/wrapper.nix   | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/nixos/modules/services/matrix/synapse.nix b/nixos/modules/services/matrix/synapse.nix
index f516c39d382b..4bcad572d069 100644
--- a/nixos/modules/services/matrix/synapse.nix
+++ b/nixos/modules/services/matrix/synapse.nix
@@ -212,6 +212,10 @@ in {
 
           Extras will automatically be enabled, when the relevant
           configuration sections are present.
+
+          Please note that this option is additive: i.e. when adding a new item
+          to this list, the defaults are still kept. To override the defaults as well,
+          use `lib.mkForce`.
         '';
       };
 
diff --git a/pkgs/servers/matrix-synapse/wrapper.nix b/pkgs/servers/matrix-synapse/wrapper.nix
index 6be1e7af7fab..930142c5f55e 100644
--- a/pkgs/servers/matrix-synapse/wrapper.nix
+++ b/pkgs/servers/matrix-synapse/wrapper.nix
@@ -12,7 +12,7 @@
 }:
 
 let
-  extraPackages = lib.concatMap (extra: matrix-synapse-unwrapped.optional-dependencies.${extra}) extras;
+  extraPackages = lib.concatMap (extra: matrix-synapse-unwrapped.optional-dependencies.${extra}) (lib.unique extras);
 
   pluginsEnv = matrix-synapse-unwrapped.python.buildEnv.override {
     extraLibs = plugins;