diff --git a/nixos/doc/manual/Makefile b/nixos/doc/manual/Makefile
index b86a76005753..b2b6481b20c7 100644
--- a/nixos/doc/manual/Makefile
+++ b/nixos/doc/manual/Makefile
@@ -1,5 +1,5 @@
.PHONY: all
-all: manual-combined.xml format
+all: manual-combined.xml
.PHONY: debug
debug: generated manual-combined.xml
diff --git a/nixos/doc/manual/development/writing-documentation.xml b/nixos/doc/manual/development/writing-documentation.xml
index 32e00544ceff..89fab6665616 100644
--- a/nixos/doc/manual/development/writing-documentation.xml
+++ b/nixos/doc/manual/development/writing-documentation.xml
@@ -25,7 +25,8 @@
$ cd /path/to/nixpkgs/nixos/doc/manual
-$ make
+$ nix-shell
+nix-shell$ make