diff --git a/manylinux/do-build.sh b/manylinux/do-build.sh
index 844b7ef5..0dfdcf0b 100755
--- a/manylinux/do-build.sh
+++ b/manylinux/do-build.sh
@@ -93,7 +93,7 @@ for pyver in $PYTHONS; do
     do_build $pyver
 done
 
-if [ -n $INTERACTIVE ]; then
+if [ "$INTERACTIVE" == "yes" ]; then
     exec /bin/bash -i
 fi
 
diff --git a/manylinux/tasks.py b/manylinux/tasks.py
index eb950825..2870c512 100644
--- a/manylinux/tasks.py
+++ b/manylinux/tasks.py
@@ -60,6 +60,6 @@ def build(ctx, pythons='', keep=False, interactive=False, arch='x86_64'):
     pythons = pythons.split(',')
     pythons = ' '.join(pythons)
     cmd = f'/scripts/do-build.sh {version} {pythons}'
-    extra = '-e INTERACTIVE=1' if interactive else ''
+    extra = '-e INTERACTIVE=yes' if interactive else ''
     run(ctx, cmd, keep, extra, arch)