diff --git a/.gitignore b/.gitignore
index 4031de4..cb42f4f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,7 +2,7 @@
 
 # cowsay-specific stuff to exclude
 
-# (nothing here currently)
+build/
 
 # Local artifacts and output files and the like 
 
diff --git a/Makefile b/Makefile
index 43d9f61..fcfe805 100644
--- a/Makefile
+++ b/Makefile
@@ -50,7 +50,7 @@ all:
 
 .PHONY: clean
 clean:
-	@echo "Nothing to do - 'make clean' is a no-op."
+	rm -rf build
 
 # The 'man' target creates cowsay.1, cowthink.1, and other man pages.
 #
@@ -75,7 +75,8 @@ man: man/man1/cowsay.1
 # than just irrelevant metadata.
 man/man1/cowsay.1: man-src/man1/cowsay.1.adoc man-src/normalize-manpage.sed
 	@set -e; \
-	tmpdir="tmp$$$$"; \
+	if ! test -d build; then mkdir build; fi; \
+	tmpdir="build/tmp$$$$"; \
 	if $(ASCIIDOCTOR) -b manpage -D "$$tmpdir/man/man1" man-src/man1/cowsay.1.adoc; then \
 	  sed -f man-src/normalize-manpage.sed man/man1/cowsay.1 > "$$tmpdir/man/man1/normalized-old-cowsay.1"; \
 	  sed -f man-src/normalize-manpage.sed "$$tmpdir/man/man1/cowsay.1" > "$$tmpdir/man/man1/normalized-new-cowsay.1"; \