diff --git a/nix/conftest.py b/nix/conftest.py
new file mode 100644
index 00000000000..6cc5d68de42
--- /dev/null
+++ b/nix/conftest.py
@@ -0,0 +1,11 @@
+import platform
+import pytest
+
+ALL = set(["aarch64", "x86_64"])
+
+
+def pytest_runtest_setup(item):
+    supported_platforms = ALL.intersection(mark.name for mark in item.iter_markers())
+    plat = platform.machine()
+    if supported_platforms and plat not in supported_platforms:
+        pytest.skip("platform specific test; not running on {}".format(plat))
diff --git a/nix/pyenv.nix b/nix/pyenv.nix
index cfe9d46e258..15f43e041fd 100644
--- a/nix/pyenv.nix
+++ b/nix/pyenv.nix
@@ -35,7 +35,7 @@ let
     };
 in pkgs.python310.withPackages (ps:
   [
-    ps.pep8
+    ps.autopep8
     ps.pytest
     ps.pytest-xdist
     ps.pytest-rerunfailures
diff --git a/nix/pytest.ini b/nix/pytest.ini
new file mode 100644
index 00000000000..1394e7d6a8d
--- /dev/null
+++ b/nix/pytest.ini
@@ -0,0 +1,4 @@
+[pytest]
+markers =
+    aarch64: tests that should pass on aarch64
+    x86_64: tests that should pass on x86_64
diff --git a/nix/shell.sh b/nix/shell.sh
index 198afb6df30..278ffd62333 100644
--- a/nix/shell.sh
+++ b/nix/shell.sh
@@ -1,6 +1,7 @@
-echo nix/shell.sh: Entering a devShell
+echo nix/shell.sh: Entering a devShell...checking environment.
 export SRC_ROOT=$(pwd)
 export PATH=$SRC_ROOT/build/bin:$PATH
+pytest -rfs -v ./nix/test_devshell.py
 
 banner()
 {
@@ -9,7 +10,6 @@ banner()
     echo "+---------------------------------------------------------+"
 }
 
-
 function clean {
     banner "Cleanup ./build"
     rm -rf ./build
diff --git a/nix/test_devshell.py b/nix/test_devshell.py
new file mode 100755
index 00000000000..e410e782298
--- /dev/null
+++ b/nix/test_devshell.py
@@ -0,0 +1,70 @@
+import os
+import shutil
+import subprocess
+import pytest
+
+
+ALL_LCS = ["openssl-3.0", "openssl-1.1.1",
+           "openssl-1.0.2", "libressl", "aws-lc"]
+
+
+def translate_lc(lc: str):
+    # awslc for S2N_LIBCRYPTO is special.
+    if "awslc" in lc:
+        return "aws-lc"
+    else:
+        return lc
+
+
+@pytest.mark.parametrize("lc", [os.getenv("S2N_LIBCRYPTO")])
+def test_s2n_libcrypto(lc):
+    # Validate S2N_LIBCRYPTO is in the CMAKE_INCLUDE_PATH
+    assert lc is not None
+    libcrypto = translate_lc(lc)
+    include_path = os.getenv("CMAKE_INCLUDE_PATH")
+    assert include_path is not None
+    assert libcrypto in ALL_LCS
+    assert libcrypto in include_path
+
+
+@pytest.mark.parametrize("lc", [os.getenv("S2N_LIBCRYPTO")])
+def test_s2n_libcrypto_uniq(lc):
+    # Make certain we only have the preferred libcrypto in CMAKE_INCLUDE_PATH.
+    assert lc is not None
+    libcrypto = translate_lc(lc)
+    include_path = os.getenv("CMAKE_INCLUDE_PATH")
+    assert include_path is not None
+    negative_lc = ALL_LCS
+    negative_lc.remove(libcrypto)
+    for library in negative_lc:
+        assert library not in include_path
+
+
+@pytest.mark.parametrize("cmd,expected,version", [
+    ("gnutls-serv", "gnutls-serv 3.7", "--version"),
+    ("gnutls-cli", "gnutls-cli 3.7", "--version"),
+    ("openssl", "OpenSSL 1.1.1", "version"),
+    ("java", "Corretto-17", "--version")])
+def test_utility_versions(cmd, expected, version):
+    # Valildate utility is in the path and the correct version.
+    abspath = shutil.which(cmd)
+    result = ""
+    with subprocess.Popen([abspath, version], shell=False, stdout=subprocess.PIPE) as p:
+        output = p.stdout.readlines()
+        for line in output:
+            result += line.decode().strip()
+        ' '.join(result)
+        assert expected in result
+
+
+def test_python():
+    # Validate python _from nix_ is in the PATH.
+    assert 'nix' in shutil.which('python')
+
+
+def test_pytest():
+    # Validate pytest _from nix_ is in the PATH.
+    assert 'nix' in shutil.which('pytest')
+
+if __name__ == "__main__":
+    print("Use pytest")