diff --git a/var/spack/repos/builtin/packages/gptune/package.py b/var/spack/repos/builtin/packages/gptune/package.py
index d96c86b074e0dc..508857d3477652 100644
--- a/var/spack/repos/builtin/packages/gptune/package.py
+++ b/var/spack/repos/builtin/packages/gptune/package.py
@@ -66,7 +66,7 @@ def cmake_args(self):
             fc_flags.append('-fallow-argument-mismatch')
 
         args = [
-            '-DGPTUNE_INSTALL_PATH=%s' % site_packages_dir,
+            '-DGPTUNE_INSTALL_PATH=%s' % python_platlib,
             '-DTPL_BLAS_LIBRARIES=%s' % spec['blas'].libs.joined(";"),
             '-DTPL_LAPACK_LIBRARIES=%s' % spec['lapack'].libs.joined(";"),
             '-DTPL_SCALAPACK_LIBRARIES=%s' % spec['scalapack'].
@@ -92,7 +92,7 @@ def cache_test_sources(self):
         self.cache_extra_test_sources([self.examples_src_dir])
 
     def setup_run_environment(self, env):
-        env.set('GPTUNE_INSTALL_PATH', site_packages_dir)
+        env.set('GPTUNE_INSTALL_PATH', python_platlib)
 
     def test(self):
         spec = self.spec
@@ -142,7 +142,7 @@ def test(self):
             envfile.write('export MPIRUN={0}\n'.format
                           (which(spec['mpi'].prefix.bin + '/mpirun')))
             envfile.write('export PYTHONPATH={0}:$PYTHONPATH\n'.format
-                          (site_packages_dir + '/gptune'))
+                          (python_platlib + '/gptune'))
             envfile.write('export proc=$(spack arch)\n')
             envfile.write('export mpi={0}\n'.format(spec['mpi'].name))
             envfile.write('export compiler={0}\n'.format(comp_name))
@@ -183,7 +183,7 @@ def test(self):
                           '{\\\"nodes\\\":$nodes,\\\"cores\\\":$cores}}}") \n')
 
         # copy the environment configuration files to non-cache directories
-        op = ['run_env.sh', site_packages_dir + '/gptune/.']
+        op = ['run_env.sh', python_platlib + '/gptune/.']
         self.run_test('cp', options=op, work_dir=wd)
         op = ['run_env.sh', self.install_test_root + '/.']
         self.run_test('cp', options=op, work_dir=wd)
diff --git a/var/spack/repos/builtin/packages/py-gpy/package.py b/var/spack/repos/builtin/packages/py-gpy/package.py
index a981d0be469336..e7ff0563c6fadf 100644
--- a/var/spack/repos/builtin/packages/py-gpy/package.py
+++ b/var/spack/repos/builtin/packages/py-gpy/package.py
@@ -22,3 +22,4 @@ class PyGpy(PythonPackage):
     depends_on('py-six', type=('build', 'run'))
     depends_on('py-paramz@0.9.0:', type=('build', 'run'))
     depends_on('py-cython@0.29:', type='build')
+    depends_on("python@:3.8", type=("build", "run"))