diff --git a/Makefile b/Makefile
index 1ee616d8..ffe2e8a3 100644
--- a/Makefile
+++ b/Makefile
@@ -7,6 +7,9 @@ COVERAGE_DIR?=$(shell mktemp -d)
 GOOS=$(shell go env GOHOSTOS)
 GOARCH=$(shell go env GOHOSTARCH)
 
+# Unit Tests and some sysmte tests rely on expired certificates, turn back the time
+export TEST_FAKETIME := 2025-01-02 03:04:05
+
 # export CAPUTRE=1 for regenrating test gold files
 ifeq ($(CAPTURE),1)
 CAPTURE_ARG := --capture
@@ -90,7 +93,7 @@ test: prepare swagger etcd-install  ## Run unit tests (add TEST=regex to specify
 	@echo "\e[33m\e[1mStarting etcd ...\e[0m"
 	@mkdir -p /tmp/aptly-etcd-data; system/t13_etcd/start-etcd.sh > /tmp/aptly-etcd-data/etcd.log 2>&1 &
 	@echo "\e[33m\e[1mRunning go test ...\e[0m"
-	faketime '2025-01-02 03:04:05' go test -v ./... -gocheck.v=true -check.f "$(TEST)" -coverprofile=unit.out; echo $$? > .unit-test.ret
+	faketime "$(TEST_FAKETIME)" go test -v ./... -gocheck.v=true -check.f "$(TEST)" -coverprofile=unit.out; echo $$? > .unit-test.ret
 	@echo "\e[33m\e[1mStopping etcd ...\e[0m"
 	@pid=`cat /tmp/etcd.pid`; kill $$pid
 	@rm -f /tmp/aptly-etcd-data/etcd.log
@@ -104,7 +107,7 @@ system-test: prepare swagger etcd-install  ## Run system tests
 	if [ ! -e ~/aptly-fixture-pool ]; then git clone https://github.com/aptly-dev/aptly-fixture-pool.git ~/aptly-fixture-pool/; fi
 	test -f ~/etcd.db || (curl -o ~/etcd.db.xz http://repo.aptly.info/system-tests/etcd.db.xz && xz -d ~/etcd.db.xz)
 	# Run system tests
-	PATH=$(BINPATH)/:$(PATH) FORCE_COLOR=1 faketime '2025-01-02 03:04:05' $(PYTHON) system/run.py --long --coverage-dir $(COVERAGE_DIR) $(CAPTURE_ARG) $(TEST)
+	PATH=$(BINPATH)/:$(PATH) FORCE_COLOR=1 $(PYTHON) system/run.py --long --coverage-dir $(COVERAGE_DIR) $(CAPTURE_ARG) $(TEST)
 
 bench:
 	@echo "\e[33m\e[1mRunning benchmark ...\e[0m"
diff --git a/system/lib.py b/system/lib.py
index 3f95b102..f7761997 100644
--- a/system/lib.py
+++ b/system/lib.py
@@ -130,6 +130,7 @@ class BaseTest(object):
     sortOutput = False
     debugOutput = False
     EtcdServer = None
+    faketime = False
 
     aptlyDir = ".aptly"
     aptlyConfigFile = ".aptly.conf"
@@ -311,6 +312,9 @@ class BaseTest(object):
             aptly_testing_bin = Path(__file__).parent / ".." / "aptly.test"
             command = [str(aptly_testing_bin), f"-test.coverprofile={Path(self.coverage_dir) / self.__class__.__name__}-{uuid4()}.out", *command[1:]]
 
+        if self.faketime:
+            command = ["faketime", os.environ.get("TEST_FAKETIME", "2025-01-02 03:04:05")] + command
+
         environ = os.environ.copy()
         environ["LC_ALL"] = "C"
         environ.update(self.environmentOverride)
diff --git a/system/s3_lib.py b/system/s3_lib.py
index 4a52b9ad..6e622b2d 100644
--- a/system/s3_lib.py
+++ b/system/s3_lib.py
@@ -24,7 +24,9 @@ class S3Test(BaseTest):
     s3Overrides = {}
 
     def fixture_available(self):
-        return super(S3Test, self).fixture_available() and s3_conn is not None
+        return super(S3Test, self).fixture_available() and \
+                'AWS_SECRET_ACCESS_KEY' in os.environ and 'AWS_ACCESS_KEY_ID' in os.environ and \
+                os.environ['AWS_SECRET_ACCESS_KEY'] != "" and os.environ['AWS_ACCESS_KEY_ID'] != ""
 
     def prepare(self):
         self.bucket_name = "aptly-sys-test-" + str(uuid.uuid1())
diff --git a/system/t04_mirror/create.py b/system/t04_mirror/create.py
index a2cdbf74..351bb20e 100644
--- a/system/t04_mirror/create.py
+++ b/system/t04_mirror/create.py
@@ -416,6 +416,7 @@ class CreateMirror31Test(BaseTest):
     runCmd = "aptly mirror create --keyring=aptlytest-gpg1.gpg mirror11 http://repo.aptly.info/system-tests/archive.debian.org/debian-archive/debian/ stretch"
     configOverride = {"gpgProvider": "internal", "max-tries": 1}
     fixtureGpg = True
+    faketime = True
 
     def outputMatchPrepare(self, s):
         return re.sub(r'Signature made .* using', '', s)