diff --git a/bec_widgets/utils/plugin_utils.py b/bec_widgets/utils/plugin_utils.py
index bf672e6c..711e46af 100644
--- a/bec_widgets/utils/plugin_utils.py
+++ b/bec_widgets/utils/plugin_utils.py
@@ -325,19 +325,117 @@ def _collect_classes_from_package(repo_name: str, package: str) -> BECClassConta
     return collection
 
 
+def _build_ast_inheritance_map(
+    repo_name: str, packages: tuple[str, ...]
+) -> dict[str, tuple[str, set[str]]]:
+    """
+    Walk all candidate modules in the given packages and return a map of:
+        class_name -> (module_name, {direct_base_names})
+
+    This is used for the transitive-closure widget discovery so that subclasses
+    of discovered widget bases are themselves discoverable without needing to
+    repeat ``PLUGIN = True`` on every intermediate or leaf class.
+    """
+    mapping: dict[str, tuple[str, set[str]]] = {}
+    for package in packages:
+        try:
+            package_roots = _find_package_roots(f"{repo_name}.{package}")
+        except ModuleNotFoundError:
+            continue
+        for directory in package_roots:
+            for root, _, files in sorted(os.walk(directory)):
+                for file_name in sorted(files):
+                    if (
+                        not file_name.endswith(".py")
+                        or file_name.startswith("__")
+                        or file_name.startswith("register_")
+                        or file_name.endswith("_plugin.py")
+                    ):
+                        continue
+                    path = os.path.join(root, file_name)
+                    rel_dir = os.path.dirname(os.path.relpath(path, directory))
+                    module_name = (
+                        file_name.removesuffix(".py")
+                        if rel_dir in ("", ".")
+                        else ".".join(rel_dir.split(os.sep) + [file_name.removesuffix(".py")])
+                    )
+                    full_module = f"{repo_name}.{package}.{module_name}"
+                    with open(path, encoding="utf-8") as fh:
+                        tree = ast.parse(fh.read(), filename=path)
+                    for node in tree.body:
+                        if not isinstance(node, ast.ClassDef):
+                            continue
+                        base_names = {_ast_node_name(b) for b in node.bases} - {None}
+                        mapping[node.name] = (full_module, base_names)  # type: ignore[arg-type]
+    return mapping
+
+
 @lru_cache(maxsize=32)
 def _cached_custom_class_references(
     repo_name: str, packages: tuple[str, ...]
 ) -> tuple[BECClassReference, ...]:
+    """Discover widget/connector class references using a transitive-closure AST scan.
+
+    The first pass identifies classes that directly inherit from
+    ``_DISCOVERY_BASE_NAMES`` or carry explicit RPC markers (``PLUGIN``,
+    ``USER_ACCESS``, ``RPC_CONTENT_CLASS``).  Subsequent passes treat every
+    newly found class name as an additional base name, so subclasses of
+    subclasses are discovered automatically — without requiring each
+    intermediate class to repeat ``PLUGIN = True``.
+    """
+    inheritance_map = _build_ast_inheritance_map(repo_name, packages)
+
+    # Seed with _class_has_rpc_markers — we need the AST nodes for that check.
+    # Re-parse only to identify initial RPC-marker classes; inheritance_map
+    # already has everything else we need.
+    rpc_marker_names: set[str] = set()
+    for package in packages:
+        try:
+            package_roots = _find_package_roots(f"{repo_name}.{package}")
+        except ModuleNotFoundError:
+            continue
+        for directory in package_roots:
+            for root, _, files in sorted(os.walk(directory)):
+                for file_name in sorted(files):
+                    if (
+                        not file_name.endswith(".py")
+                        or file_name.startswith("__")
+                        or file_name.startswith("register_")
+                        or file_name.endswith("_plugin.py")
+                    ):
+                        continue
+                    path = os.path.join(root, file_name)
+                    with open(path, encoding="utf-8") as fh:
+                        tree = ast.parse(fh.read(), filename=path)
+                    for node in tree.body:
+                        if isinstance(node, ast.ClassDef) and _class_has_rpc_markers(node):
+                            rpc_marker_names.add(node.name)
+
+    # Transitive closure: start with known base names + RPC-marker classes,
+    # then repeatedly add classes whose direct bases are already known.
+    known: set[str] = set(_DISCOVERY_BASE_NAMES) | rpc_marker_names
+    changed = True
+    while changed:
+        changed = False
+        for class_name, (_, bases) in inheritance_map.items():
+            if class_name not in known and bases & known:
+                known.add(class_name)
+                changed = True
+
+    # Build the final list of references, preserving first-seen order and
+    # keeping only classes that are in the inheritance map (i.e. have a module).
     references: list[BECClassReference] = []
     seen_names: set[str] = set()
-    for package in packages:
-        for module_name, _, class_names in _iter_candidate_modules(repo_name, package):
-            for class_name in class_names:
-                if class_name in seen_names:
-                    continue
-                references.append(BECClassReference(name=class_name, module=module_name))
-                seen_names.add(class_name)
+    for class_name, (module_name, bases) in inheritance_map.items():
+        if class_name not in known:
+            continue
+        if class_name in seen_names:
+            continue
+        # Only emit if the class is actually a candidate (not just a raw base)
+        if class_name in _DISCOVERY_BASE_NAMES:
+            continue
+        references.append(BECClassReference(name=class_name, module=module_name))
+        seen_names.add(class_name)
     return tuple(references)
 
 
diff --git a/tests/end-2-end/test_rpc_widgets_e2e.py b/tests/end-2-end/test_rpc_widgets_e2e.py
index 19e8109f..fb83cafa 100644
--- a/tests/end-2-end/test_rpc_widgets_e2e.py
+++ b/tests/end-2-end/test_rpc_widgets_e2e.py
@@ -89,13 +89,6 @@ def test_available_widgets(qtbot, connected_client_gui_obj):
         # Skip private attributes
         if object_name.startswith("_"):
             continue
-        # Skip BECShell as ttyd is not installed
-        if object_name == "BECShell":
-            continue
-
-        # Skip BecConsole as ttyd is not installed
-        if object_name == "BecConsole":
-            continue
 
         #############################
         ######### Add widget ########