diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0c11e626e..002fd763c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -582,9 +582,10 @@ jobs:
           make
       - name: create amalgamation
         run: |
-          build/qjs amalgam.js $RUNNER_TEMP/quickjs-amalgam.c
+          make amalgam
       - name: build amalgamation
         run: |
+          unzip -d $RUNNER_TEMP build/quickjs-amalgam.zip
           cc -Wall -I. -o $RUNNER_TEMP/run-test262.o -c run-test262.c
           cc -Wall -I/ -DQJS_BUILD_LIBC -o $RUNNER_TEMP/quickjs-amalgam.o -c $RUNNER_TEMP/quickjs-amalgam.c
           cc -o $RUNNER_TEMP/run-test262 $RUNNER_TEMP/run-test262.o $RUNNER_TEMP/quickjs-amalgam.o -lm
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 7f137d4df..fc433c43d 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -50,9 +50,7 @@ jobs:
           cd build
           cmake -DCMAKE_OSX_ARCHITECTURES="x86_64;arm64" ..
           make -j$(getconf _NPROCESSORS_ONLN)
-          (cd .. && build/qjs amalgam.js build/quickjs-amalgam.c)
-          cp ../quickjs.h .
-          zip -9 quickjs-amalgam.zip quickjs-amalgam.c quickjs.h
+          make -C .. amalgam # writes build/quickjs-amalgam.zip
           mv qjs qjs-darwin
           mv qjsc qjsc-darwin
       - name: check
diff --git a/Makefile b/Makefile
index 982ce16c3..403461dad 100644
--- a/Makefile
+++ b/Makefile
@@ -45,6 +45,15 @@ endif
 
 all: $(QJS)
 
+amalgam: TEMP := $(shell mktemp -d)
+amalgam: $(QJS)
+	$(QJS) amalgam.js $(TEMP)/quickjs-amalgam.c
+	cp quickjs.h quickjs-libc.h $(TEMP)
+	cd $(TEMP) && zip -9 quickjs-amalgam.zip quickjs-amalgam.c quickjs.h quickjs-libc.h
+	cp $(TEMP)/quickjs-amalgam.zip $(BUILD_DIR)
+	cd $(TEMP) && $(RM) quickjs-amalgam.zip quickjs-amalgam.c quickjs.h quickjs-libc.h
+	$(RM) -d $(TEMP)
+
 fuzz:
 	clang -g -O1 -fsanitize=address,undefined,fuzzer -o fuzz fuzz.c
 	./fuzz
@@ -117,4 +126,4 @@ unicode_gen: $(BUILD_DIR)
 libunicode-table.h: unicode_gen
 	$(BUILD_DIR)/unicode_gen unicode $@
 
-.PHONY: all ctest cxxtest debug fuzz install clean codegen distclean stats test test262 test262-update test262-check microbench unicode_gen $(QJS) $(QJSC)
+.PHONY: all amalgam ctest cxxtest debug fuzz install clean codegen distclean stats test test262 test262-update test262-check microbench unicode_gen $(QJS) $(QJSC)