GTK+ Developer Matthias Clasen gtk-builder-tool 1 User Commands gtk-builder-tool GtkBuilder file utility gtk-builder-tool COMMAND FILE gtk-builder-tool can perform various operations on GtkBuilder .ui files. The following commands are understood: validate Validate the .ui file and report errors to stderr. simplify Simplify the .ui file by removing properties that are set to their default values and write the resulting XML to stdout.