do not rebuild static files all the time

scripts/Makefile.static

@@ -7,11 +7,27 @@ GZ = $(patsubst %,%.gz,$(SRCS))
 .PHONY: all
 all: $(ZSTD) $(BR) $(GZ)
 
-%.br: %
+define MAKETARGET
-	brotli $<
 
-%.zst: %
+$(1).br: $(1).xxhash
-	zstd -19 $<
+	brotli -f $(1)
+	touch $(1).br
 
-%.gz: %
+$(1).zst: $(1).xxhash
-	zopfli $<
+	zstd -f -19 $(1)
+	touch $(1).zst
+
+$(1).gz: $(1).xxhash
+	zopfli $(1)
+	touch $(1).gz
+
+# https://github.com/gohugoio/hugo/issues/10842
+$(1).xxhash: $(1)
+	current=$$$$(xxhsum $$< | cut -d' ' -f1); \
+	if [ ! -f $$< ] || [ "$$$$(cat $$@ 2>/dev/null)" != "$$$$current" ]; then \
+		echo "$$$$current" > $$@; \
+	fi
+
+endef
+
+$(foreach f,$(SRCS),$(eval $(call MAKETARGET,$(f))))

scripts/build

@@ -2,6 +2,6 @@
 set -xeuo pipefail
 cd "$(git rev-parse --show-toplevel)"
 
-hugo --cleanDestinationDir --printPathWarnings --panicOnWarning
+hugo --printPathWarnings --panicOnWarning
 
 find public -type d | xargs -P4 -n1 make -j4 -sf $PWD/scripts/Makefile.static -C