diff --git a/shared/sx/ref/boundary_parser.py b/shared/sx/ref/boundary_parser.py
index d51dee5..20b924d 100644
--- a/shared/sx/ref/boundary_parser.py
+++ b/shared/sx/ref/boundary_parser.py
@@ -36,13 +36,22 @@ def _ref_dir() -> str:
 
 
 def _project_root() -> str:
-    """Return the project root (3 levels up from shared/sx/ref/)."""
+    """Return the project root containing service directories.
+
+    Dev:    shared/sx/ref -> shared/sx -> shared -> project root
+    Docker: /app/shared/sx/ref -> /app (shared is inside /app)
+    """
     ref = _ref_dir()
-    # shared/sx/ref -> shared/sx -> shared -> project root
+    # Go up 3 levels: shared/sx/ref -> project root
     root = os.path.abspath(os.path.join(ref, "..", "..", ".."))
-    # In Docker the layout is /app/shared/sx/ref -> /app
-    if not os.path.isdir(root):
-        root = os.path.abspath(os.path.join(ref, "..", ".."))
+    # Verify by checking for a known service directory or shared/
+    if os.path.isdir(os.path.join(root, "shared")):
+        return root
+    # Docker: /app/shared/sx/ref -> /app
+    # shared is INSIDE /app, not a sibling — go up to parent of shared
+    root = os.path.abspath(os.path.join(ref, "..", ".."))
+    if os.path.isdir(os.path.join(root, "sx")):  # /app/sx exists in Docker
+        return root
     return root
 
 
@@ -98,12 +107,25 @@ def _extract_declarations(
 
 
 def _find_service_boundary_files() -> list[str]:
-    """Find all {service}/sx/boundary.sx files in the project."""
+    """Find service boundary.sx files.
+
+    Dev:    {project}/{service}/sx/boundary.sx (e.g. blog/sx/boundary.sx)
+    Docker: /app/sx/boundary.sx (service's sx/ dir copied directly into /app/)
+    """
     root = _project_root()
-    pattern = os.path.join(root, "*/sx/boundary.sx")
-    files = glob.glob(pattern)
-    # Exclude shared/sx/ref/ — that's the core boundary
-    return [f for f in files if "/shared/" not in f]
+    files: list[str] = []
+
+    # Dev layout: {root}/{service}/sx/boundary.sx
+    for f in glob.glob(os.path.join(root, "*/sx/boundary.sx")):
+        if "/shared/" not in f:
+            files.append(f)
+
+    # Docker layout: service's sx/ dir is at {root}/sx/boundary.sx
+    docker_path = os.path.join(root, "sx", "boundary.sx")
+    if os.path.exists(docker_path) and docker_path not in files:
+        files.append(docker_path)
+
+    return files
 
 
 # ---------------------------------------------------------------------------