diff --git a/stackinator/builder.py b/stackinator/builder.py
index 33d4727..6dea8f5 100644
--- a/stackinator/builder.py
+++ b/stackinator/builder.py
@@ -234,7 +234,11 @@ def generate(self, recipe):
         git_commit_result = subprocess.run(
             ["git", "-C", spack_path, "rev-parse", "HEAD"], shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE
         )
-        spack_meta = {"commit": git_commit_result.stdout.strip().decode("utf-8"), "url": spack["repo"]}
+        spack_meta = {
+            "ref": spack["commit"],
+            "commit": git_commit_result.stdout.strip().decode("utf-8"),
+            "url": spack["repo"],
+        }
 
         # load the jinja templating environment
         template_path = self.root / "templates"
diff --git a/stackinator/etc/envvars.py b/stackinator/etc/envvars.py
index 384fc9b..63ca1a0 100755
--- a/stackinator/etc/envvars.py
+++ b/stackinator/etc/envvars.py
@@ -535,7 +535,7 @@ def meta_impl(args):
         }
 
     if args.spack is not None:
-        spack_url, spack_version = args.spack.split(",")
+        spack_url, spack_ref, spack_commit = args.spack.split(",")
         spack_path = f"{args.mount}/config".replace("//", "/")
         meta["views"]["spack"] = {
             "activate": "/dev/null",
@@ -548,7 +548,8 @@ def meta_impl(args):
                     "list": {},
                     "scalar": {
                         "UENV_SPACK_CONFIG_PATH": spack_path,
-                        "UENV_SPACK_COMMIT": spack_version,
+                        "UENV_SPACK_REF": spack_ref,
+                        "UENV_SPACK_COMMIT": spack_commit,
                         "UENV_SPACK_URL": spack_url,
                     },
                 },
@@ -586,7 +587,10 @@ def meta_impl(args):
     uenv_parser.add_argument("mount", help="mount point of the image", type=str)
     uenv_parser.add_argument("--modules", help="configure a module view", action="store_true")
     uenv_parser.add_argument(
-        "--spack", help='configure a spack view. Format is "spack_url,git_commit"', type=str, default=None
+        "--spack",
+        help='configure a spack view. Format is "spack_url,git_ref,git_commit"',
+        type=str,
+        default=None,
     )
 
     args = parser.parse_args()
diff --git a/stackinator/templates/Makefile b/stackinator/templates/Makefile
index 8404981..f43595d 100644
--- a/stackinator/templates/Makefile
+++ b/stackinator/templates/Makefile
@@ -69,7 +69,7 @@ modules-done: environments generate-config
 
 env-meta: generate-config environments{% if modules %} modules-done{% endif %}
 
-	$(SANDBOX) $(BUILD_ROOT)/envvars.py uenv {% if modules %}--modules{% endif %} --spack={{ spack_meta.url }},{{ spack_meta.commit }} $(STORE)
+	$(SANDBOX) $(BUILD_ROOT)/envvars.py uenv {% if modules %}--modules{% endif %} --spack='{{ spack_meta.url }},{{ spack_meta.ref }},{{ spack_meta.commit }}' $(STORE)
 	touch env-meta
 
 post-install: env-meta