diff --git a/lang/python/tests/Makefile.am b/lang/python/tests/Makefile.am
index 25b15f2b..3864f8ba 100644
--- a/lang/python/tests/Makefile.am
+++ b/lang/python/tests/Makefile.am
@@ -1,123 +1,120 @@
 # Makefile.am for the tests of the Python bindings.
 # Copyright (C) 2016 g10 Code GmbH
 #
 # This file is part of GPGME.
 #
 # GPGME is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 2 of the License, or
 # (at your option) any later version.
 #
 # GPGME is distributed in the hope that it will be useful, but WITHOUT
 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
 # Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with this program; if not, see <http://www.gnu.org/licenses/>.
 
 GPG = gpg
 GPG_AGENT = gpg-agent
-export GNUPGHOME := $(abs_builddir)
-export GPG_AGENT_INFO :=
 
 test_srcdir = $(top_srcdir)/tests/gpg
 
 TESTS_ENVIRONMENT = GNUPGHOME=$(abs_builddir) \
 	LC_ALL=C GPG_AGENT_INFO= \
 	top_srcdir=$(top_srcdir) \
 	srcdir=$(srcdir) \
 	LD_LIBRARY_PATH="../../../src/.libs:$(LD_LIBRARY_PATH)"
 
 py_tests = t-wrapper.py \
 	t-callbacks.py \
 	t-data.py \
 	t-encrypt.py \
 	t-encrypt-sym.py \
 	t-encrypt-sign.py \
 	t-sign.py \
 	t-signers.py \
 	t-decrypt.py \
 	t-verify.py \
 	t-decrypt-verify.py \
 	t-sig-notation.py \
 	t-export.py \
 	t-import.py \
 	t-trustlist.py \
 	t-edit.py \
 	t-keylist.py \
 	t-keylist-from-data.py \
 	t-wait.py \
 	t-encrypt-large.py \
 	t-file-name.py \
 	t-idiomatic.py \
 	t-protocol-assuan.py \
 	t-quick-key-creation.py \
 	t-quick-subkey-creation.py \
 	t-quick-key-manipulation.py \
 	t-quick-key-signing.py
 
 XTESTS = initial.py $(py_tests) final.py
 EXTRA_DIST = support.py $(XTESTS) encrypt-only.asc sign-only.asc \
              run-tests.py
 
 # XXX: Currently, one cannot override automake's 'check' target.  As a
 # workaround, we avoid defining 'TESTS', thus automake will not emit
 # the 'check' target.  For extra robustness, we merely define a
 # dependency on 'xcheck', so this hack should also work even if
 # automake would emit the 'check' target, as adding dependencies to
 # targets is okay.
 check: xcheck
 
 .PHONY: xcheck
 
 xcheck:	all
 	$(TESTS_ENVIRONMENT) $(PYTHON) $(srcdir)/run-tests.py \
 	  --interpreters="$(PYTHONS)" --srcdir=$(srcdir) $(TESTFLAGS) \
 	  $(XTESTS)
 
 CLEANFILES = secring.gpg pubring.gpg pubring.kbx trustdb.gpg dirmngr.conf \
 	gpg-agent.conf pubring.kbx~ gpg.conf pubring.gpg~ \
 	random_seed .gpg-v21-migrated tofu.db \
-        pubring-stamp private-keys-v1.d/gpg-sample.stamp
+        pubring-stamp gpg-sample.stamp
 
 private_keys = \
         $(test_srcdir)/13CD0F3BDF24BE53FE192D62F18737256FF6E4FD \
         $(test_srcdir)/76F7E2B35832976B50A27A282D9B87E44577EB66 \
         $(test_srcdir)/A0747D5F9425E6664F4FFBEED20FBCA79FDED2BD \
         $(test_srcdir)/13CBE3758AFE42B5E5E2AE4CED27AFA455E3F87F \
         $(test_srcdir)/7A030357C0F253A5BBCD282FFC4E521B37558F5C
 
 clean-local:
-	-$(top_srcdir)/tests/start-stop-agent --stop
+	-$(TESTS_ENVIRONMENT) $(top_srcdir)/tests/start-stop-agent --stop
 	-rm -fR -- private-keys-v1.d openpgp-revocs.d S.gpg-agent sshcontrol
 
 
 BUILT_SOURCES = gpg.conf gpg-agent.conf pubring-stamp \
-           private-keys-v1.d/gpg-sample.stamp
+           gpg-sample.stamp
 
-private-keys-v1.d/gpg-sample.stamp: $(private_keys)
-	-gpgconf --kill all
+gpg-sample.stamp: $(private_keys)
+	-$(TESTS_ENVIRONMENT) gpgconf --kill all
 	$(MKDIR_P) ./private-keys-v1.d
 	for k in $(private_keys); do \
           cp $$k private-keys-v1.d/$${k#$(test_srcdir)/}.key; \
         done
-	echo x > ./private-keys-v1.d/gpg-sample.stamp
+	echo x > ./gpg-sample.stamp
 
-pubring-stamp: $(test_srcdir)/pubdemo.asc           \
-                 ./private-keys-v1.d/gpg-sample.stamp
-	$(GPG) --batch --no-permission-warning \
+pubring-stamp: $(test_srcdir)/pubdemo.asc gpg-sample.stamp
+	$(TESTS_ENVIRONMENT) $(GPG) --batch --no-permission-warning \
                --import $(test_srcdir)/pubdemo.asc
-	-$(GPG) --batch --no-permission-warning \
+	-$(TESTS_ENVIRONMENT) $(GPG) --batch --no-permission-warning \
 		--import $(test_srcdir)/secdemo.asc
 	echo x > ./pubring-stamp
 
 gpg.conf:
 # This is required for t-sig-notations.
 	echo no-force-v3-sigs > ./gpg.conf
 	echo ignore-invalid-option agent-program >> ./gpg.conf
 	echo "agent-program `which $(GPG_AGENT)`|--debug-quick-random" >> ./gpg.conf
 
 gpg-agent.conf:
 # This is required for gpg2, which does not support command fd.
 	echo pinentry-program $(abs_top_srcdir)/tests/gpg/pinentry >$@
diff --git a/lang/qt/tests/Makefile.am b/lang/qt/tests/Makefile.am
index a662b4cf..104672e4 100644
--- a/lang/qt/tests/Makefile.am
+++ b/lang/qt/tests/Makefile.am
@@ -1,96 +1,94 @@
 # Makefile.am - Makefile for GPGME Qt tests.
 # Copyright (C) 2016 Bundesamt für Sicherheit in der Informationstechnik
 # Software engineering by Intevation GmbH
 #
 # This file is part of GPGME.
 #
 # GPGME is free software; you can redistribute it and/or modify it
 # under the terms of the GNU Lesser General Public License as
 # published by the Free Software Foundation; either version 2.1 of the
 # License, or (at your option) any later version.
 #
 # GPGME is distributed in the hope that it will be useful, but WITHOUT
 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
 # Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with this program; if not, see <http://www.gnu.org/licenses/>.
 
 ## Process this file with automake to produce Makefile.in
 
 GPG = gpg
 
 TESTS_ENVIRONMENT = GNUPGHOME=$(abs_builddir)
 
 EXTRA_DIST = initial.test
 
 TESTS = initial.test t-keylist t-keylocate t-ownertrust t-tofuinfo \
         t-encrypt t-verify t-various t-config
 
 moc_files = t-keylist.moc t-keylocate.moc t-ownertrust.moc t-tofuinfo.moc \
             t-encrypt.moc t-support.hmoc t-wkspublish.moc t-verify.moc \
             t-various.moc t-config.moc
 
 AM_LDFLAGS = -no-install
 
 LDADD = ../../cpp/src/libgpgmepp.la ../src/libqgpgme.la \
         ../../../src/libgpgme.la @GPGME_QT_LIBS@ @GPG_ERROR_LIBS@ \
         @GPGME_QTTEST_LIBS@ -lstdc++
 
 AM_CPPFLAGS = -I$(top_srcdir)/lang/cpp/src -I$(top_builddir)/src \
               @GPG_ERROR_CFLAGS@ @GPGME_QT_CFLAGS@ @GPG_ERROR_CFLAGS@ \
               @LIBASSUAN_CFLAGS@ @GPGME_QTTEST_CFLAGS@ -DBUILDING_QGPGME \
               -I$(top_srcdir)/lang/qt/src \
               -DTOP_SRCDIR="$(top_srcdir)"
 
 support_src = t-support.h t-support.cpp
 
 t_keylist_SOURCES = t-keylist.cpp $(support_src)
 t_keylocate_SOURCES = t-keylocate.cpp $(support_src)
 t_ownertrust_SOURCES = t-ownertrust.cpp $(support_src)
 t_tofuinfo_SOURCES = t-tofuinfo.cpp $(support_src)
 t_encrypt_SOURCES = t-encrypt.cpp $(support_src)
 t_wkspublish_SOURCES = t-wkspublish.cpp $(support_src)
 t_verify_SOURCES = t-verify.cpp $(support_src)
 t_various_SOURCES = t-various.cpp $(support_src)
 t_config_SOURCES = t-config.cpp $(support_src)
 run_keyformailboxjob_SOURCES = run-keyformailboxjob.cpp
 
 nodist_t_keylist_SOURCES = $(moc_files)
 
 BUILT_SOURCES = $(moc_files) pubring-stamp
 
 noinst_PROGRAMS = t-keylist t-keylocate t-ownertrust t-tofuinfo t-encrypt \
     run-keyformailboxjob t-wkspublish t-verify t-various t-config
 
 CLEANFILES = secring.gpg pubring.gpg pubring.kbx trustdb.gpg dirmngr.conf \
 	gpg-agent.conf pubring.kbx~ S.gpg-agent gpg.conf pubring.gpg~ \
 	random_seed S.gpg-agent .gpg-v21-migrated pubring-stamp $(moc_files) \
 	gpg.conf tofu.db
 
 clean-local:
-	-$(top_srcdir)/tests/start-stop-agent --stop
+	-$(TESTS_ENVIRONMENT) $(top_srcdir)/tests/start-stop-agent --stop
 	-rm -fR  private-keys-v1.d crls.d
 
-export GNUPGHOME := $(abs_builddir)
-
 pubring-stamp: $(top_srcdir)/tests/gpg/pubdemo.asc \
 	             $(top_srcdir)/tests/gpg/secdemo.asc
-	-gpgconf --kill all
+	-$(TESTS_ENVIRONMENT) gpgconf --kill all
 	echo "ignore-invalid-option allow-loopback-pinentry" > $(abs_builddir)/gpg-agent.conf
 	echo "allow-loopback-pinentry" >> gpg-agent.conf
 	echo "ignore-invalid-option pinentry-mode" > gpg.conf
 	echo "pinentry-mode loopback" >> gpg.conf
-	$(GPG) --no-permission-warning \
+	$(TESTS_ENVIRONMENT) $(GPG) --no-permission-warning \
            --import $(top_srcdir)/tests/gpg/pubdemo.asc
-	$(GPG) --no-permission-warning \
+	$(TESTS_ENVIRONMENT) $(GPG) --no-permission-warning \
 		   --passphrase "abc" \
            --import $(top_srcdir)/tests/gpg/secdemo.asc
 	touch pubring-stamp
 
 .cpp.moc:
 	$(MOC) `test -f '$<' || echo '$(srcdir)/'`$< -o $@
 
 .h.hmoc:
 	$(MOC) `test -f '$<' || echo '$(srcdir)/'`$< -o $@
diff --git a/tests/gpg/Makefile.am b/tests/gpg/Makefile.am
index 034bb5e0..b50f4b07 100644
--- a/tests/gpg/Makefile.am
+++ b/tests/gpg/Makefile.am
@@ -1,112 +1,108 @@
 # Copyright (C) 2000 Werner Koch (dd9jn)
 # Copyright (C) 2001, 2004, 2005, 2009 g10 Code GmbH
 #
 # This file is part of GPGME.
 #
 # GPGME is free software; you can redistribute it and/or modify it
 # under the terms of the GNU Lesser General Public License as
 # published by the Free Software Foundation; either version 2.1 of the
 # License, or (at your option) any later version.
 #
 # GPGME is distributed in the hope that it will be useful, but WITHOUT
 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
 # Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 
 ## Process this file with automake to produce Makefile.in
 
 GPG = gpg
 GPG_AGENT = gpg-agent
 
 TESTS_ENVIRONMENT = GNUPGHOME=$(abs_builddir) LC_ALL=C GPG_AGENT_INFO= \
                     top_srcdir=$(top_srcdir)
 
 # The keylist tests must come after the import and the edit test.
 noinst_HEADERS = t-support.h
 
 if HAVE_W32_SYSTEM
 tests_unix =
 else
 tests_unix = t-eventloop t-thread1 t-thread-keylist t-thread-keylist-verify
 endif
 
 c_tests = \
         t-encrypt t-encrypt-sym t-encrypt-sign t-sign t-signers		\
 	t-decrypt t-verify t-decrypt-verify t-sig-notation t-export	\
 	t-import t-trustlist t-edit t-keylist t-keylist-sig t-wait	\
 	t-encrypt-large t-file-name t-gpgconf t-encrypt-mixed \
 	$(tests_unix)
 
 TESTS = initial.test $(c_tests) final.test
 
 CLEANFILES = secring.gpg pubring.gpg pubring.kbx trustdb.gpg dirmngr.conf \
 	gpg-agent.conf pubring.kbx~ S.gpg-agent gpg.conf pubring.gpg~ \
 	random_seed S.gpg-agent .gpg-v21-migrated pubring-stamp \
 	gpg-sample.stamp tofu.db *.conf.gpgconf.bak
 
 private_keys = \
         13CD0F3BDF24BE53FE192D62F18737256FF6E4FD \
         76F7E2B35832976B50A27A282D9B87E44577EB66 \
         A0747D5F9425E6664F4FFBEED20FBCA79FDED2BD \
         13CBE3758AFE42B5E5E2AE4CED27AFA455E3F87F \
         7A030357C0F253A5BBCD282FFC4E521B37558F5C
 
 
 EXTRA_DIST = initial.test final.test \
         pubdemo.asc secdemo.asc cipher-1.asc cipher-2.asc \
 	geheim.txt pubkey-1.asc seckey-1.asc pinentry $(private_keys)
 
 BUILT_SOURCES = gpg.conf gpg-agent.conf pubring-stamp \
            gpg-sample.stamp
 AM_CPPFLAGS = -I$(top_builddir)/src @GPG_ERROR_CFLAGS@
 AM_LDFLAGS = -no-install
 LDADD = ../../src/libgpgme.la
 t_thread1_LDADD = ../../src/libgpgme.la -lpthread
 t_thread_keylist_LDADD = ../../src/libgpgme.la -lpthread
 t_thread_keylist_verify_LDADD = ../../src/libgpgme.la -lpthread
 t_cancel_LDADD = ../../src/libgpgme.la -lpthread
 
 # We don't run t-genkey and t-cancel in the test suite, because it
 # takes too long
 tests_skipped = t-genkey
 if !HAVE_W32_SYSTEM
 tests_skipped += t-cancel
 endif
 
 noinst_PROGRAMS = $(c_tests) $(tests_skipped)
 
 
 clean-local:
-	-$(top_srcdir)/tests/start-stop-agent --stop
+	-$(TESTS_ENVIRONMENT) $(top_srcdir)/tests/start-stop-agent --stop
 	-rm -fR private-keys-v1.d
 
-export GNUPGHOME := $(abs_builddir)
-
-export GPG_AGENT_INFO :=
-
 gpg-sample.stamp: $(srcdir)/$(private_keys)
-	-gpgconf --kill all
+	-$(TESTS_ENVIRONMENT) gpgconf --kill all
 	$(MKDIR_P) ./private-keys-v1.d
 	for k in $(private_keys); do \
           cp $(srcdir)/$$k private-keys-v1.d/$$k.key; \
         done
 	echo x > ./gpg-sample.stamp
 
 pubring-stamp: $(srcdir)/pubdemo.asc gpg-sample.stamp
-	$(GPG) --batch --no-permission-warning \
+	$(TESTS_ENVIRONMENT) $(GPG) --batch --no-permission-warning \
                --import $(srcdir)/pubdemo.asc
-	-$(GPG) --batch --no-permission-warning \
+	-$(TESTS_ENVIRONMENT) $(GPG) --batch --no-permission-warning \
 		--import $(srcdir)/secdemo.asc
 	echo x > ./pubring-stamp
 
 gpg.conf:
 # This is required for t-sig-notations.
 	echo no-force-v3-sigs > ./gpg.conf
 
 gpg-agent.conf:
 # This is required for gpg2, which does not support command fd.
 	echo pinentry-program $(abs_srcdir)/pinentry > ./gpg-agent.conf
diff --git a/tests/gpgsm/Makefile.am b/tests/gpgsm/Makefile.am
index 3b8eb725..d2acd05b 100644
--- a/tests/gpgsm/Makefile.am
+++ b/tests/gpgsm/Makefile.am
@@ -1,82 +1,78 @@
 # Copyright (C) 2000 Werner Koch (dd9jn)
 # Copyright (C) 2001 g10 Code GmbH
 #
 # This file is part of GPGME.
 #
 # GPGME is free software; you can redistribute it and/or modify it
 # under the terms of the GNU Lesser General Public License as
 # published by the Free Software Foundation; either version 2.1 of the
 # License, or (at your option) any later version.
 #
 # GPGME is distributed in the hope that it will be useful, but WITHOUT
 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
 # Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 
 ## Process this file with automake to produce Makefile.in
 
 GPGSM = gpgsm
 GPG_AGENT = gpg-agent
 
 TESTS_ENVIRONMENT = GNUPGHOME=$(abs_builddir) LC_ALL=C GPG_AGENT_INFO= \
                     top_srcdir=$(top_srcdir)
 
 noinst_HEADERS = t-support.h
 
 c_tests = t-import t-keylist t-encrypt t-verify t-decrypt t-sign t-export
 
 
 TESTS = initial.test $(c_tests) final.test
 
 EXTRA_DIST = cert_dfn_pca01.der cert_dfn_pca15.der cert_g10code_test1.der \
 	$(key_id) initial.test final.test
 
 AM_CPPFLAGS = -I$(top_builddir)/src @GPG_ERROR_CFLAGS@
 AM_LDFLAGS = -no-install
 LDADD = ../../src/libgpgme.la
 
 # We don't run t-genkey in the test suite, because it takes too long
 # and needs a working pinentry.
 noinst_PROGRAMS = $(c_tests) t-genkey cms-keylist cms-decrypt
 
 key_id = 32100C27173EF6E9C4E9A25D3D69F86D37A4F939
 
 CLEANFILES = pubring-stamp pubring.kbx pubring.kbx~ gpgsm.conf trustlist.txt \
 	random_seed S.gpg-agent gpg-sample.stamp
 
 clean-local:
-	-$(top_srcdir)/tests/start-stop-agent --stop
+	-$(TESTS_ENVIRONMENT) $(top_srcdir)/tests/start-stop-agent --stop
 	-rm -fR private-keys-v1.d
 
-export GNUPGHOME := $(abs_builddir)
-
-export GPG_AGENT_INFO :=
-
 BUILT_SOURCES = gpgsm.conf trustlist.txt pubring-stamp \
            gpg-sample.stamp
 
 pubring-stamp: $(srcdir)/cert_g10code_test1.der gpg-sample.stamp
-	$(GPGSM) --import $(srcdir)/cert_g10code_test1.der
+	$(TESTS_ENVIRONMENT) $(GPGSM) --import $(srcdir)/cert_g10code_test1.der
 	touch pubring-stamp
 
 gpgsm.conf:
 	echo disable-crl-checks > ./gpgsm.conf
 	echo faked-system-time 1008241200 >> ./gpgsm.conf
 	echo "agent-program `which $(GPG_AGENT)`|--debug-quick-random" >> ./gpgsm.conf
 
 gpg-sample.stamp: $(srcdir)/$(key_id)
-	-gpgconf --kill all
+	-$(TESTS_ENVIRONMENT) gpgconf --kill all
 	$(MKDIR_P) ./private-keys-v1.d
 	cp $(srcdir)/$(key_id) private-keys-v1.d/$(key_id).key
 	echo x > ./gpg-sample.stamp
 
 trustlist.txt:
 	echo $(key_id) > ./trustlist.txt
 	echo >> ./trustlist.txt
 	echo "# CN=test cert 1,OU=Aegypten Project,O=g10 Code GmbH,L=Düsseldorf,C=DE" >> ./trustlist.txt
 	echo "3CF405464F66ED4A7DF45BBDD1E4282E33BDB76E S" >> ./trustlist.txt