diff --git a/Makefile b/Makefile
index b38c82e..a07deb8 100644
--- a/Makefile
+++ b/Makefile
@@ -12,242 +12,253 @@
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
+DESTDIR ?= output
 
 all: \
-	acpica-unix2-20220331.tar.gz \
-	acpica-unix2-20211217.tar.gz \
-	acpica-unix2-20210930.tar.gz \
-	acpica-unix2-20210730.tar.gz \
-	acpica-unix2-20210604.tar.gz \
-	acpica-unix2-20210331.tar.gz \
-	acpica-unix2-20210105.tar.gz \
-	acpica-unix2-20201217.tar.gz \
-	acpica-unix2-20201113.tar.gz \
-	acpica-unix2-20200925.tar.gz \
-	acpica-unix2-20200717.tar.gz \
-	acpica-unix2-20200528.tar.gz \
-	acpica-unix2-20200430.tar.gz \
-	acpica-unix2-20200326.tar.gz \
-	acpica-unix2-20200214.tar.gz \
-	acpica-unix2-20200110.tar.gz \
-	acpica-unix2-20191213.tar.gz \
-	acpica-unix2-20191018.tar.gz \
-	acpica-unix2-20190816.tar.gz \
-	acpica-unix2-20190703.tar.gz \
-	acpica-unix2-20190509.tar.gz \
-	acpica-unix2-20190405.tar.gz \
-	acpica-unix2-20190215.tar.gz \
-	acpica-unix2-20180810.tar.gz \
-	acpica-unix2-20180629.tar.gz \
-	acpica-unix2-20180531.tar.gz \
-	acpica-unix2-20180508.tar.gz \
-	acpica-unix2-20180427.tar.gz \
-	acpica-unix2-20180313.tar.gz \
-	acpica-unix2-20180209.tar.gz \
-	acpica-unix2-20171110.tar.gz \
-	acpica-unix2-20150410.tar.gz \
+	$(DESTDIR)/acpica-unix2-20220331.tar.gz \
+	$(DESTDIR)/acpica-unix2-20210930.tar.gz \
+	$(DESTDIR)/acpica-unix2-20210730.tar.gz \
+	$(DESTDIR)/acpica-unix2-20210604.tar.gz \
+	$(DESTDIR)/acpica-unix2-20210331.tar.gz \
+	$(DESTDIR)/acpica-unix2-20200925.tar.gz \
+	$(DESTDIR)/acpica-unix2-20200717.tar.gz \
+	$(DESTDIR)/acpica-unix2-20200110.tar.gz \
+	$(DESTDIR)/acpica-unix2-20191213.tar.gz \
+	$(DESTDIR)/acpica-unix2-20191018.tar.gz \
+	$(DESTDIR)/acpica-unix2-20190816.tar.gz \
+	$(DESTDIR)/acpica-unix2-20190703.tar.gz \
+	$(DESTDIR)/acpica-unix2-20190509.tar.gz \
+	$(DESTDIR)/acpica-unix2-20190405.tar.gz \
+	$(DESTDIR)/acpica-unix2-20190215.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180810.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180629.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180531.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180508.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180427.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180313.tar.gz \
+	$(DESTDIR)/acpica-unix2-20180209.tar.gz \
+	$(DESTDIR)/acpica-unix2-20171110.tar.gz \
+
+# Fails to build:
+# - $(DESTDIR)/acpica-unix2-20211217.tar.gz
+# - $(DESTDIR)/acpica-unix2-20210105.tar.gz
+# - $(DESTDIR)/acpica-unix2-20201217.tar.gz
+# - $(DESTDIR)/acpica-unix2-20201113.tar.gz
+# - $(DESTDIR)/acpica-unix2-20200528.tar.gz
+# - $(DESTDIR)/acpica-unix2-20200430.tar.gz
+# - $(DESTDIR)/acpica-unix2-20200326.tar.gz
+# - $(DESTDIR)/acpica-unix2-20200214.tar.gz
+# - $(DESTDIR)/acpica-unix2-20200110.tar.gz
+# - $(DESTDIR)/acpica-unix2-20191213.tar.gz
 
 # 0bb0984724 gnu: acpica: Update to 20220331.
-acpica-unix2-20220331.tar.gz:
+$(DESTDIR)/acpica-unix2-20220331.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v1.4.0 -- build --source acpica` \
 	$@
 
 # 67c72c8c70 gnu: acpica: Update to 20211217.
-acpica-unix2-20211217.tar.gz:
+$(DESTDIR)/$(DESTDIR)/acpica-unix2-20211217.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=67c72c8c70 -- build --source acpica` \
 	$@
 
 # 2cced18b76 gnu: acpica: Update to 20210930.
-acpica-unix2-20210930.tar.gz:
+$(DESTDIR)/acpica-unix2-20210930.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=2cced18b76 -- build --source acpica` \
 	$@
 
 # f25304236a gnu: acpica: Update to 20210730.
-acpica-unix2-20210730.tar.gz:
+$(DESTDIR)/acpica-unix2-20210730.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=f25304236a -- build --source acpica` \
 	$@
 
 # c4d9c9cb3f gnu: acpica: Update to 20210604.
-acpica-unix2-20210604.tar.gz:
+$(DESTDIR)/acpica-unix2-20210604.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=c4d9c9cb3f -- build --source acpica` \
 	$@
 
 # 4ebf6ccb3e gnu: acpica: Update to 20210331.
-acpica-unix2-20210331.tar.gz:
+$(DESTDIR)/acpica-unix2-20210331.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v1.3.0 -- build --source acpica` \
 	$@
 
 # ee858defb2 gnu: acpica: Update to 20210105.
-acpica-unix2-20210105.tar.gz:
+$(DESTDIR)/acpica-unix2-20210105.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=ee858defb2 -- build --source acpica` \
 	$@
 
 # 4904d31e88 gnu: acpica: Update to 20201217.
-acpica-unix2-20201217.tar.gz:
+$(DESTDIR)/acpica-unix2-20201217.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=4904d31e88 -- build --source acpica` \
 	$@
 
 # c8edef614c gnu: acpica: Update to 20201113.
-acpica-unix2-20201113.tar.gz:
+$(DESTDIR)/acpica-unix2-20201113.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=c8edef614c -- build --source acpica` \
 	$@
 
 # d265e61f50 gnu: acpica: Update to 20200925.
-acpica-unix2-20200925.tar.gz:
+$(DESTDIR)/acpica-unix2-20200925.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=d265e61f50 -- build --source acpica` \
 	$@
 
 # 2b4dc589e9 gnu: acpica: Update to 20200717.
-acpica-unix2-20200717.tar.gz:
+$(DESTDIR)/acpica-unix2-20200717.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v1.2.0 -- build --source acpica` \
 	$@
 
 # 0792984459 gnu: acpica: Update to 20200528.
-acpica-unix2-20200528.tar.gz:
+$(DESTDIR)/acpica-unix2-20200528.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=0792984459 -- build --source acpica` \
 	$@
 
 # c1ca686bc8 gnu: acpica: Update to 20200430.
-acpica-unix2-20200430.tar.gz:
+$(DESTDIR)/acpica-unix2-20200430.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=c1ca686bc8 -- build --source acpica` \
 	$@
 
 # 75083257ac gnu: acpica: Update to 20200326.
-acpica-unix2-20200326.tar.gz:
+$(DESTDIR)/acpica-unix2-20200326.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v1.1.0 -- build --source acpica` \
 	$@
 
 # ec09abc6ac gnu: acpica: Update to 20200214.
-acpica-unix2-20200214.tar.gz:
+$(DESTDIR)/acpica-unix2-20200214.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=ec09abc6ac -- build --source acpica` \
 	$@
 
 # 762b2af6c6 gnu: acpica: Update to 20200110.
-acpica-unix2-20200110.tar.gz:
+$(DESTDIR)/acpica-unix2-20200110.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=762b2af6c6 -- build --source acpica` \
 	$@
 
 # 401298ba94 gnu: acpica: Update to 20191213.
-acpica-unix2-20191213.tar.gz:
+$(DESTDIR)/acpica-unix2-20191213.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=401298ba94 -- build --source acpica` \
 	$@
 
 # b577306a92 gnu: acpica: Update to 20191018.
-acpica-unix2-20191018.tar.gz:
+$(DESTDIR)/acpica-unix2-20191018.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=b577306a92 -- build --source acpica` \
 	$@
 
 # b439d9b290 gnu: acpica: Update to 20190816.
-acpica-unix2-20190816.tar.gz:
+$(DESTDIR)/acpica-unix2-20190816.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=b439d9b290 -- build --source acpica` \
 	$@
 
 # 347b4c47b4 gnu: acpica: Update to 20190703.
-acpica-unix2-20190703.tar.gz:
+$(DESTDIR)/acpica-unix2-20190703.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=347b4c47b4 -- build --source acpica` \
 	$@
 
 # 2ce144eebb gnu: acpica: Update to 20190509.
-acpica-unix2-20190509.tar.gz:
+$(DESTDIR)/acpica-unix2-20190509.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v1.0.1 -- build --source acpica` \
 	$@
 
 # 7710b8f8ad gnu: acpica: Update to 20190405.
-acpica-unix2-20190405.tar.gz:
+$(DESTDIR)/acpica-unix2-20190405.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v1.0.0 -- build --source acpica` \
 	$@
 
 # 70c8b1ec30 gnu: acpica: Update to 20190215.
-acpica-unix2-20190215.tar.gz:
+$(DESTDIR)/acpica-unix2-20190215.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=70c8b1ec30 -- build --source acpica` \
 	$@
 
 # 9b1125bc6c gnu: acpica: Update to 20180810.
-acpica-unix2-20180810.tar.gz:
+$(DESTDIR)/acpica-unix2-20180810.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=9b1125bc6c -- build --source acpica` \
 	$@
 
 # 8ef7ecf469 gnu: acpica: Update to 20180629.
-acpica-unix2-20180629.tar.gz:
+$(DESTDIR)/acpica-unix2-20180629.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=8ef7ecf469 -- build --source acpica` \
 	$@
 
 # 84979374c2 gnu: acpica: Update to 20180531.
-acpica-unix2-20180531.tar.gz:
+$(DESTDIR)/acpica-unix2-20180531.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=84979374c2 -- build --source acpica` \
 	$@
 
 # ab3950d809 gnu: acpica: Update to 20180508.
-acpica-unix2-20180508.tar.gz:
+$(DESTDIR)/acpica-unix2-20180508.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=ab3950d809 -- build --source acpica` \
 	$@
 
 # e56feffec0 gnu: acpica: Update to 20180427.
-acpica-unix2-20180427.tar.gz:
+$(DESTDIR)/acpica-unix2-20180427.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=e56feffec0 -- build --source acpica` \
 	$@
 
 # 8027f84d8f gnu: acpica: Update to 20180313.
-acpica-unix2-20180313.tar.gz:
+$(DESTDIR)/acpica-unix2-20180313.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=8027f84d8f -- build --source acpica` \
 	$@
 
 # 6577611b2b gnu: acpica: Update to 20180209.
-acpica-unix2-20180209.tar.gz:
+$(DESTDIR)/acpica-unix2-20180209.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=6577611b2b -- build --source acpica` \
 	$@
 
 # 4a462aa7f4 gnu: acpica: Update to 20171110.
-acpica-unix2-20171110.tar.gz:
+$(DESTDIR)/acpica-unix2-20171110.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=4a462aa7f4 -- build --source acpica` \
 	$@
 
 # 2036a6484e gnu: acpica: Update to 20150410.
-acpica-unix2-20150410.tar.gz:
+$(DESTDIR)/acpica-unix2-20150410.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v0.9.0 -- build --source acpica` \
 	$@
 
 # 13c8c2bf13 gnu: Add acpica.
-acpica-unix2-20140724.tar.gz:
+$(DESTDIR)/acpica-unix2-20140724.tar.gz:
 	install -m 644 \
 	`guix time-machine --commit=v0.8 -- build --source acpica` \
 	$@
 
+$(DESTDIR)/acpica-unix2-20210331.tar.gz.sha1: acpica-unix2-20210331.tar.gz.sha1
+	install -m 644 \
+	acpica-unix2-20210331.tar.gz.sha1 \
+	$(DESTDIR)
+
 .PHONY: check-acpica-unix2-20210331.tar.gz
-check-acpica-unix2-20210331.tar.gz.sha1: acpica-unix2-20210331.tar.gz.sha1
-	sha1sum -c $^.sha1
+check-acpica-unix2-20210331.tar.gz: \
+		$(DESTDIR)/acpica-unix2-20210331.tar.gz \
+		$(DESTDIR)/acpica-unix2-20210331.tar.gz.sha1
+	cd $(DESTDIR) && sha1sum -c acpica-unix2-20210331.tar.gz.sha1
 
 # Maintenance tools
 .PHONY: Makefile.new