diff --git a/recipes/incoming-kde/libX11.toml b/recipes/incoming-kde/libX11.toml
index f19329f4..b79c9e27 100644
--- a/recipes/incoming-kde/libX11.toml
+++ b/recipes/incoming-kde/libX11.toml
@@ -29,4 +29,6 @@ compile   = "make -j\"$(nproc)\""
 install   = "make install DESTDIR=/out"
 
 [deps]
-build = ["pkgconf", "python3", "util-macros", "xorgproto", "xcb-proto", "libxcb", "xtrans"]
+# libXau+libXdmcp: libxcb.pc los declara en Requires.private ⇒ pkg-config los exige transitivamente al
+# resolver xcb (sin sus .pc: "Package 'xdmcp', required by 'xcb', not found"). Patrón .pc→[deps].build.
+build = ["pkgconf", "python3", "util-macros", "xorgproto", "xcb-proto", "libxcb", "xtrans", "libXau", "libXdmcp"]