diff --git a/Makefile b/Makefile
index 09b0637..06edc1e 100644
--- a/Makefile
+++ b/Makefile
@@ -45,10 +45,10 @@ build:
 # ------------------------------------------------------------
 
 test-unit: build-missing
-	@distro=arch scripts/test/test-unit.sh
+	@bash scripts/test/test-unit.sh
 
 test-integration: build-missing
-	@distro=arch scripts/test/test-integration.sh
+	@bash scripts/test/test-integration.sh
 
 test-e2e: build-missing
 	@bash scripts/test/test-e2e.sh
diff --git a/scripts/test/test-integration.sh b/scripts/test/test-integration.sh
index 701e15f..c9a445d 100755
--- a/scripts/test/test-integration.sh
+++ b/scripts/test/test-integration.sh
@@ -1,6 +1,8 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+: "${distro:=arch}"
+
 echo "============================================================"
 echo ">>> Running INTEGRATION tests in ${distro} container"
 echo "============================================================"
diff --git a/scripts/test/test-unit.sh b/scripts/test/test-unit.sh
index 2ab30ef..d470852 100755
--- a/scripts/test/test-unit.sh
+++ b/scripts/test/test-unit.sh
@@ -1,6 +1,8 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+: "${distro:=arch}"
+
 echo "============================================================"
 echo ">>> Running UNIT tests in ${distro} container"
 echo "============================================================"