define static location for yt-dlp binary

app/ytdlp.go

@@ -3,13 +3,17 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"os"
 	"time"
 
 	"github.com/lrstanley/go-ytdlp"
 )
 
+var ytdlpBinary = os.Getenv("YTDLP_BIN")
+
 func GetFormats(url string) (*FormatOptions, error) {
 	dl := ytdlp.New().
+		SetExecutable(ytdlpBinary).
 		SkipDownload().
 		DumpJSON()
 
@@ -100,6 +104,7 @@ func DownloadVideo(out_dir, temp_dir, url string, opts DownloadOptions, progress
 	var lastPhase string
 
 	dl := ytdlp.New().
+		SetExecutable(ytdlpBinary).
 		Paths(homePath).
 		Paths(tempPath).
 		RecodeVideo("mp4").

flake.nix

@@ -46,6 +46,8 @@
                         .venv/bin/pip install -r ./app/requirements.txt
                         source .venv/bin/activate
                     fi
+
+                    export YTDLP_BIN=${pkgs.lib.getExe pkgs.yt-dlp}
                 '';
             };
         });