diff --git a/.github/workflows/ci-release.yml b/.github/workflows/ci-release.yml
index 804e2f5a..e0cbb5b1 100644
--- a/.github/workflows/ci-release.yml
+++ b/.github/workflows/ci-release.yml
@@ -53,6 +53,10 @@ jobs:
       - name: Run tests
         run: uv run pytest
 
+      - name: Run no-xorq-compatible examples
+        if: matrix.name == 'no-xorq'
+        run: make examples-core
+
   # Build examples, docs, and skills (require the full env incl. Node).
   build:
     name: Build (examples + docs + skills)
diff --git a/Makefile b/Makefile
index 175df596..b486e7d1 100644
--- a/Makefile
+++ b/Makefile
@@ -15,6 +15,7 @@ help:
 	@echo "  make test IBIS_VERSION=all             - Run tests with all ibis versions (9.5.0, 10.8.0, 11.0.0)"
 	@echo "  make test IBIS_VERSION=10.8.0          - Run tests with specific ibis version"
 	@echo "  make examples                          - Run all example scripts"
+	@echo "  make examples-core                     - Run no-xorq-compatible examples"
 	@echo "  make examples IBIS_VERSION=all         - Run examples with all ibis versions"
 	@echo "  make examples IBIS_VERSION=10.8.0      - Run examples with specific ibis version"
 	@echo "  make docs-build                        - Build documentation"
@@ -105,6 +106,19 @@ else
 	@echo "✓ All examples passed!"
 endif
 
+examples-core:
+	@echo "Running no-xorq-compatible examples..."
+	@for file in \
+		scripts/demo_bsl_v2.py \
+		examples/quickstart.py \
+		examples/window_functions.py \
+		examples/bucketing_with_other.py \
+		examples/sessionized_data.py; do \
+		echo "Running $$file..."; \
+		uv run --with . "$$file" || exit 1; \
+	done
+	@echo "✓ No-xorq-compatible examples passed!"
+
 # Build docs
 docs-build:
 	@echo "Building documentation..."
diff --git a/examples/bucketing_with_other.py b/examples/bucketing_with_other.py
index 14640307..86112807 100644
--- a/examples/bucketing_with_other.py
+++ b/examples/bucketing_with_other.py
@@ -9,6 +9,10 @@
 import ibis
 from ibis import _
 
+# CI runs this example with and without xorq. xibis matches BSL's active ibis
+# flavor in both modes; users who are not using xorq can simply use `import ibis`.
+from boring_semantic_layer._xorq import ibis as xibis
+
 from boring_semantic_layer import from_yaml
 
 
@@ -28,13 +32,13 @@ def main():
             nest={"data": lambda t: t.group_by(["code", "elevation"])},
         )
         .mutate(
-            rank=lambda t: ibis.row_number().over(
-                ibis.window(order_by=ibis.desc(t.avg_elevation)),
+            rank=lambda t: xibis.row_number().over(
+                xibis.window(order_by=xibis.desc(t.avg_elevation)),
             ),
         )
         .mutate(
             is_other=lambda t: t.rank > 4,
-            state_grouped=lambda t: ibis.ifelse(t.rank > 4, "OTHER", t.state),
+            state_grouped=lambda t: xibis.ifelse(t.rank > 4, "OTHER", t.state),
         )
         .group_by("state_grouped")
         .aggregate(
diff --git a/examples/quickstart.py b/examples/quickstart.py
index 02f1bf3d..a5dfbb12 100644
--- a/examples/quickstart.py
+++ b/examples/quickstart.py
@@ -13,6 +13,10 @@
 import ibis
 import pandas as pd
 
+# CI runs this example with and without xorq. xibis matches BSL's active ibis
+# flavor in both modes; users who are not using xorq can simply use `import ibis`.
+from boring_semantic_layer._xorq import ibis as xibis
+
 from boring_semantic_layer import to_semantic_table
 
 
@@ -111,7 +115,7 @@ def main():
         .with_measures(sum_val=lambda t: t.value.sum())
     )
 
-    rolling_window = ibis.window(order_by="date", rows=(1, 1))
+    rolling_window = xibis.window(order_by="date", rows=(1, 1))
     expr4 = (
         ts_st.group_by("date")
         .aggregate("sum_val")
diff --git a/examples/sessionized_data.py b/examples/sessionized_data.py
index 24630e65..a38a52a9 100644
--- a/examples/sessionized_data.py
+++ b/examples/sessionized_data.py
@@ -13,6 +13,10 @@
 import ibis
 import pandas as pd
 
+# CI runs this example with and without xorq. xibis matches BSL's active ibis
+# flavor in both modes; users who are not using xorq can simply use `import ibis`.
+from boring_semantic_layer._xorq import ibis as xibis
+
 from boring_semantic_layer import from_yaml, to_untagged
 
 # Show all columns in output
@@ -31,7 +35,7 @@ def main():
 
     # Filter for carrier WN on 2002-03-03 and add flight_date column
     filtered_flights = flights.filter(
-        lambda t: (t.carrier == "WN") & (t.dep_time.date() == ibis.date(2002, 3, 3)),
+        lambda t: (t.carrier == "WN") & (t.dep_time.date() == xibis.date(2002, 3, 3)),
     ).mutate(flight_date=lambda t: t.dep_time.date())
 
     # Create sessions with nested flight legs
@@ -52,7 +56,7 @@ def main():
                 ]),
             },
         )
-        .mutate(session_id=ibis.row_number().over(ibis.window()))
+        .mutate(session_id=xibis.row_number().over(xibis.window()))
         .order_by("session_id")
     )
 
diff --git a/examples/window_functions.py b/examples/window_functions.py
index d56805bd..fa996f44 100644
--- a/examples/window_functions.py
+++ b/examples/window_functions.py
@@ -4,6 +4,10 @@
 import ibis
 from ibis import _
 
+# CI runs this example with and without xorq. xibis matches BSL's active ibis
+# flavor in both modes; users who are not using xorq can simply use `import ibis`.
+from boring_semantic_layer._xorq import ibis as xibis
+
 from boring_semantic_layer import to_semantic_table
 
 BASE_URL = "https://pub-a45a6a332b4646f2a6f44775695c64df.r2.dev"
@@ -31,13 +35,13 @@ def main():
     result = (
         daily_stats.mutate(
             rolling_avg=lambda t: t.flight_count.mean().over(
-                ibis.window(order_by=t.flight_date, preceding=6, following=0),
+                xibis.window(order_by=t.flight_date, preceding=6, following=0),
             ),
-            rank=lambda t: ibis.dense_rank().over(
-                ibis.window(order_by=ibis.desc(t.flight_count)),
+            rank=lambda t: xibis.dense_rank().over(
+                xibis.window(order_by=xibis.desc(t.flight_count)),
             ),
             running_total=lambda t: t.flight_count.sum().over(
-                ibis.window(order_by=t.flight_date),
+                xibis.window(order_by=t.flight_date),
             ),
         )
         .order_by("flight_date")
@@ -64,8 +68,8 @@ def main():
 
     result = (
         carrier_stats.mutate(
-            total_flights=lambda t: t.flight_count.sum().over(ibis.window()),
-            percent_manual=lambda t: (t.flight_count / t.flight_count.sum().over(ibis.window()))
+            total_flights=lambda t: t.flight_count.sum().over(xibis.window()),
+            percent_manual=lambda t: (t.flight_count / t.flight_count.sum().over(xibis.window()))
             * 100,
         )
         .order_by(_.percent_manual.desc())
diff --git a/scripts/demo_bsl_v2.py b/scripts/demo_bsl_v2.py
index a786064e..b65815ef 100644
--- a/scripts/demo_bsl_v2.py
+++ b/scripts/demo_bsl_v2.py
@@ -20,6 +20,10 @@
 
 from boring_semantic_layer import to_semantic_table
 
+# CI runs this demo with and without xorq. xibis matches BSL's active ibis
+# flavor in both modes; users who are not using xorq can simply use `import ibis`.
+from boring_semantic_layer._xorq import ibis as xibis
+
 
 def main():
     # Setup in-memory DuckDB
@@ -116,7 +120,7 @@ def main():
         .with_measures(sum_val=lambda t: t.value.sum())
     )
 
-    rolling_window = ibis.window(order_by="date", preceding=1, following=1)
+    rolling_window = xibis.window(order_by="date", preceding=1, following=1)
     expr4 = (
         ts_st.group_by("date")
         .aggregate("sum_val")
diff --git a/src/boring_semantic_layer/chart/tests/test_chart.py b/src/boring_semantic_layer/chart/tests/test_chart.py
index c3a40a4a..ea01aeef 100644
--- a/src/boring_semantic_layer/chart/tests/test_chart.py
+++ b/src/boring_semantic_layer/chart/tests/test_chart.py
@@ -6,9 +6,9 @@
 
 from boring_semantic_layer import to_semantic_table
 
-# BSL's to_untagged() returns xorq-vendored ibis when xorq is installed, and
-# those expressions reject a plain ibis.window (LegacyWindowBuilder). Build the
-# window from the matching flavor via the shim (plain ibis when xorq is absent).
+# Match BSL's active ibis flavor: plain ibis without xorq, xorq-vendored ibis
+# with xorq installed. Plain-ibis users can write `import ibis` directly.
+from boring_semantic_layer._xorq import ibis as xibis
 
 
 @pytest.fixture(scope="module")
@@ -390,7 +390,7 @@ def test_chart_with_dynamic_dimension_and_rolling_window(self, flights_model):
             .order_by("flight_week")
             .mutate(
                 rolling_avg=lambda t: t.flight_count.mean().over(
-                    ibis.window(rows=(-2, 0), order_by="flight_week")
+                    xibis.window(rows=(-2, 0), order_by="flight_week")
                 )
             )
         )
diff --git a/src/boring_semantic_layer/ops.py b/src/boring_semantic_layer/ops.py
index 574554f6..bb9fda16 100644
--- a/src/boring_semantic_layer/ops.py
+++ b/src/boring_semantic_layer/ops.py
@@ -740,7 +740,12 @@ def _classify_measure(
     if prefer_known is None:
         prefer_known = getattr(scope, "_prefer_known", ())
     prefer_known_set = frozenset(prefer_known)
-    expr_prefer_known = getattr(expr, "__bsl_prefer_known__", ())
+    try:
+        # Use object.__getattribute__ so ibis Deferred.__getattr__ does not
+        # synthesize a resolver for this private marker.
+        expr_prefer_known = object.__getattribute__(expr, "__bsl_prefer_known__")
+    except AttributeError:
+        expr_prefer_known = ()
     if expr_prefer_known is True:
         prefer_known_set = prefer_known_set | known_set
     else: