diff --git a/packages/hxtorch/package.py b/packages/hxtorch/package.py
index 64022dec8fd4e3b3a5fb1da38d31ff9b6bda2b91..abf1d23f40d5392369128b392c9b9c86c5f9a650 100644
--- a/packages/hxtorch/package.py
+++ b/packages/hxtorch/package.py
@@ -168,8 +168,11 @@ class Hxtorch(WafPackage):
         args = ['--test-execnone']
         return args
 
-    # def install_test(self):
-    #     with working_dir('spack-test', create=True):
-    #         old_pythonpath = os.environ.get('PYTHONPATH', '')
-    #         os.environ['PYTHONPATH'] = ':'.join([str(self.prefix.lib), old_pythonpath])
-    #         python('-v', '-X dev', '-c', 'import hxtorch; print(hxtorch.__file__)')
+    def install_test(self):
+        with working_dir('spack-test', create=True):
+            old_pythonpath = os.environ.get('PYTHONPATH', '')
+            os.environ['PYTHONPATH'] = ':'.join([str(self.prefix.lib), old_pythonpath])
+            python('-c', 'import hxtorch; print(hxtorch.__file__)')
+            # ignore exit code for now
+            cmd_true = which("true")
+            cmd_true()
diff --git a/packages/pynn-brainscales/package.py b/packages/pynn-brainscales/package.py
index ff945808eaba4f019d67530cd6c44c5b547695df..9e69e7498b6f35369889fbc415fa3ecb32e49440 100644
--- a/packages/pynn-brainscales/package.py
+++ b/packages/pynn-brainscales/package.py
@@ -144,8 +144,11 @@ class PynnBrainscales(WafPackage):
         args = ['--test-execnone']
         return args
 
-    # def install_test(self):
-    #     with working_dir('spack-test', create=True):
-    #         old_pythonpath = os.environ.get('PYTHONPATH', '')
-    #         os.environ['PYTHONPATH'] = ':'.join([str(self.prefix.lib), old_pythonpath])
-    #         python('-c', 'import pynn_brainscales; print(pynn_brainscales.__file__)')
+    def install_test(self):
+        with working_dir('spack-test', create=True):
+            old_pythonpath = os.environ.get('PYTHONPATH', '')
+            os.environ['PYTHONPATH'] = ':'.join([str(self.prefix.lib), old_pythonpath])
+            python('-c', 'import pynn_brainscales; print(pynn_brainscales.__file__)')
+            # ignore exit code for now
+            cmd_true = which("true")
+            cmd_true()