diff --git a/.github/workflows/bootstrap.yml b/.github/workflows/bootstrap.yml
new file mode 100644
index 0000000000..70fe9bf58a
--- /dev/null
+++ b/.github/workflows/bootstrap.yml
@@ -0,0 +1,113 @@
+name: Bootstrapping
+
+on:
+  pull_request:
+    branches:
+      - develop
+      - releases/**
+    paths-ignore:
+      # Don't run if we only modified packages in the
+      # built-in repository or documentation
+      - 'var/spack/repos/builtin/**'
+      - '!var/spack/repos/builtin/packages/clingo-bootstrap/**'
+      - '!var/spack/repos/builtin/packages/python/**'
+      - 'lib/spack/docs/**'
+  schedule:
+    # nightly at 2:16 AM
+    - cron: '16 2 * * *'
+
+jobs:
+
+  fedora:
+    runs-on: ubuntu-latest
+    container: "fedora:latest"
+    steps:
+      - name: Install dependencies
+        run: |
+          dnf install -y \
+              bzip2 curl file gcc-c++ gcc gcc-gfortran git gnupg2 gzip \
+              make patch unzip which xz python3 python3-devel tree \
+              cmake bison bison-devel libstdc++-static
+      - uses: actions/checkout@v2
+      - name: Setup repo and non-root user
+        run: |
+          git --version
+          git fetch --unshallow
+          . .github/workflows/setup_git.sh
+          useradd spack-test
+          chown -R spack-test .
+      - name: Bootstrap clingo
+        shell: runuser -u spack-test -- bash {0}
+        run: |
+          source share/spack/setup-env.sh
+          spack external find cmake bison
+          spack -d solve zlib
+          tree ~/.spack/bootstrap/store/
+
+  ubuntu:
+    runs-on: ubuntu-latest
+    container: "ubuntu:latest"
+    steps:
+      - name: Install dependencies
+        env:
+          DEBIAN_FRONTEND: noninteractive
+        run: |
+          apt-get update -y && apt-get upgrade -y
+          apt-get install -y \
+              bzip2 curl file g++ gcc gfortran git gnupg2 gzip \
+              make patch unzip xz-utils python3 python3-dev tree \
+              cmake bison
+      - uses: actions/checkout@v2
+      - name: Setup repo and non-root user
+        run: |
+          git --version
+          git fetch --unshallow
+          . .github/workflows/setup_git.sh
+          useradd -m spack-test
+          chown -R spack-test .
+      - name: Bootstrap clingo
+        shell: runuser -u spack-test -- bash {0}
+        run: |
+          source share/spack/setup-env.sh
+          spack external find cmake bison
+          spack -d solve zlib
+          tree ~/.spack/bootstrap/store/
+
+  opensuse:
+    runs-on: ubuntu-latest
+    container: "opensuse/tumbleweed:latest"
+    steps:
+      - name: Install dependencies
+        run: |
+          zypper update -y
+          zypper install -y \
+              bzip2 curl file gcc-c++ gcc gcc-fortran tar git gpg2 gzip \
+              make patch unzip which xz python3 python3-devel tree \
+              cmake bison
+      - uses: actions/checkout@v2
+      - name: Setup repo and non-root user
+        run: |
+          git --version
+          git fetch --unshallow
+          . .github/workflows/setup_git.sh
+      - name: Bootstrap clingo
+        run: |
+          source share/spack/setup-env.sh
+          spack external find cmake bison
+          spack -d solve zlib
+          tree ~/.spack/bootstrap/store/
+
+  macos:
+    runs-on: macos-latest
+    steps:
+      - name: Install dependencies
+        run: |
+          brew install cmake bison@2.7 tree
+      - uses: actions/checkout@v2
+      - name: Bootstrap clingo
+        run: |
+          source share/spack/setup-env.sh
+          export PATH=/usr/local/opt/bison@2.7/bin:$PATH
+          spack external find --not-buildable cmake bison
+          spack -d solve zlib
+          tree ~/.spack/bootstrap/store/
diff --git a/lib/spack/spack/bootstrap.py b/lib/spack/spack/bootstrap.py
index 92bbb2fa42..09088c3eb6 100644
--- a/lib/spack/spack/bootstrap.py
+++ b/lib/spack/spack/bootstrap.py
@@ -92,15 +92,19 @@ def make_module_available(module, spec=None, install=False):
     installed_specs = spack.store.db.query(spec, installed=True)
 
     for ispec in installed_specs:
-        # TODO: make sure run-environment is appropriate
-        module_path = ispec['python'].package.get_python_lib(prefix=ispec.prefix)
+        lib_spd = ispec['python'].package.default_site_packages_dir
+        lib64_spd = lib_spd.replace('lib/', 'lib64/')
+        module_paths = [
+            os.path.join(ispec.prefix, lib_spd),
+            os.path.join(ispec.prefix, lib64_spd)
+        ]
         try:
-            sys.path.append(module_path)
+            sys.path.extend(module_paths)
             __import__(module)
             return
         except ImportError:
             tty.warn("Spec %s did not provide module %s" % (ispec, module))
-            sys.path = sys.path[:-1]
+            sys.path = sys.path[:-2]
 
     def _raise_error(module_name, module_spec):
         error_msg = 'cannot import module "{0}"'.format(module_name)
@@ -117,13 +121,18 @@ def _raise_error(module_name, module_spec):
         spec.concretize()
     spec.package.do_install()
 
-    module_path = spec['python'].package.get_python_lib(prefix=spec.prefix)
+    lib_spd = spec['python'].package.default_site_packages_dir
+    lib64_spd = lib_spd.replace('lib/', 'lib64/')
+    module_paths = [
+        os.path.join(spec.prefix, lib_spd),
+        os.path.join(spec.prefix, lib64_spd)
+    ]
     try:
-        sys.path.append(module_path)
+        sys.path.extend(module_paths)
         __import__(module)
         return
     except ImportError:
-        sys.path = sys.path[:-1]
+        sys.path = sys.path[:-2]
         _raise_error(module, spec)
 
 
diff --git a/var/spack/repos/builtin/packages/python/package.py b/var/spack/repos/builtin/packages/python/package.py
index 61f42aaad3..760dc422c2 100644
--- a/var/spack/repos/builtin/packages/python/package.py
+++ b/var/spack/repos/builtin/packages/python/package.py
@@ -920,8 +920,12 @@ def site_packages_dir(self):
         try:
             return self.get_python_lib(prefix='')
         except (ProcessError, RuntimeError):
-            return os.path.join(
-                'lib', 'python{0}'.format(self.version.up_to(2)), 'site-packages')
+            return self.default_site_packages_dir
+
+    @property
+    def default_site_packages_dir(self):
+        python_dir = 'python{0}'.format(self.version.up_to(2))
+        return os.path.join('lib', python_dir, 'site-packages')
 
     @property
     def easy_install_file(self):