diff --git a/R/ari_narrate.R b/R/ari_narrate.R
index d6bd12c..4689d87 100644
--- a/R/ari_narrate.R
+++ b/R/ari_narrate.R
@@ -56,7 +56,7 @@ ari_narrate <- function(script, slides, output = "output.mp4", voice,
     ## call webshot:::fix_windows_url() which append his version of
     ## "file:///"..., hence if this part run on window it brake the procedure.
     #
-    if (!webshot:::is_windows()){ 
+    if (!.Platform$OS.type == "windows"){ 
       
       ## slash was missing
       #
diff --git a/R/ari_stitch.R b/R/ari_stitch.R
index 7220cbf..5235570 100644
--- a/R/ari_stitch.R
+++ b/R/ari_stitch.R
@@ -54,7 +54,7 @@ ari_stitch <- function(images, audio, output = "output.mp4"){
   ## on windows ffmpeg cancats names adding the working directory, so if
   ## complete url is provided it adds it twice.
   #
-  if (webshot:::is_windows()) images <- basename(images) 
+  if (.Platform$OS.type == "windows") images <- basename(images) 
   for(i in 1:length(images)){
     cat(paste0("file ", "'", images[i], "'", "\n"), file = input_txt_path, append = TRUE)
     cat(paste0("duration ", duration(audio[[i]]), "\n"), file = input_txt_path, append = TRUE)