diff --git a/doc/Makefile b/doc/Makefile
index ee98a3ee9213..208f23f5023a 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -19,6 +19,9 @@ pandoc_flags = --extract-media=$(pandoc_media_dir) \
 .PHONY: all
 all: validate format out/html/index.html out/epub/manual.epub
 
+.PHONY: render-md
+render-md: ${MD_TARGETS}
+
 .PHONY: debug
 debug:
 	nix-shell --run "xmloscopy --docbook5 ./manual.xml ./manual-full.xml"
diff --git a/doc/default.nix b/doc/default.nix
index ac405c379038..4f55c95a04c1 100644
--- a/doc/default.nix
+++ b/doc/default.nix
@@ -20,6 +20,10 @@ in pkgs.stdenv.mkDerivation {
     ln -s ${doc-support} ./doc-support/result
   '';
 
+  preBuild = ''
+    make -j$NIX_BUILD_CORES render-md
+  '';
+
   installPhase = ''
     dest="$out/share/doc/nixpkgs"
     mkdir -p "$(dirname "$dest")"