From 4ee1354ae6ae144d43f60e062387450f56eb3e82 Mon Sep 17 00:00:00 2001
From: June Stepp <git@junestepp.me>
Date: Tue, 15 Jul 2025 17:23:13 -0500
Subject: [PATCH] nixos/peertube: only include whisper when transcription is
 enabled

`whisper-ctranslate2` has a large closure size with unique dependencies.
---
 nixos/modules/services/web-apps/peertube.nix | 35 ++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/nixos/modules/services/web-apps/peertube.nix b/nixos/modules/services/web-apps/peertube.nix
index 2a676fd06673..76e95cfe52e0 100644
--- a/nixos/modules/services/web-apps/peertube.nix
+++ b/nixos/modules/services/web-apps/peertube.nix
@@ -165,7 +165,39 @@ in
     };
 
     settings = lib.mkOption {
-      type = settingsFormat.type;
+      type = lib.types.submodule (
+        { config, ... }:
+        {
+          freeformType = settingsFormat.type;
+          options = {
+            video_transcription = {
+              enabled = lib.mkOption {
+                type = lib.types.bool;
+                default = false;
+                description = "Enable automatic transcription of videos.";
+              };
+              engine_path = lib.mkOption {
+                type = with lib.types; either path str;
+                default =
+                  if config.video_transcription.enabled then
+                    lib.getExe pkgs.whisper-ctranslate2
+                  else
+                    # This will be in the error message when someone enables
+                    # transcription manually in the web UI and tries to run a
+                    # transcription job.
+                    "Set `services.peertube.settings.video_transcription.enabled = true`.";
+                defaultText = lib.literalExpression ''
+                  if config.services.peertube.settings.video_transcription.enabled then
+                    lib.getExe pkgs.whisper-ctranslate2
+                  else
+                    "Set `services.peertube.settings.video_transcription.enabled = true`."
+                '';
+                description = "Custom engine path for local transcription.";
+              };
+            };
+          };
+        }
+      );
       example = lib.literalExpression ''
         {
           listen = {
@@ -424,7 +456,6 @@ in
         };
         video_transcription = {
           engine = lib.mkDefault "whisper-ctranslate2";
-          engine_path = lib.mkDefault (lib.getExe pkgs.whisper-ctranslate2);
         };
       }
       (lib.mkIf cfg.redis.enableUnixSocket {