diff --git a/benchmarks/gfql/filter_pagerank/pure_rapids_string_build_repro.py b/benchmarks/gfql/filter_pagerank/pure_rapids_string_build_repro.py
new file mode 100644
index 0000000000..52ce97ab4b
--- /dev/null
+++ b/benchmarks/gfql/filter_pagerank/pure_rapids_string_build_repro.py
@@ -0,0 +1,146 @@
+#!/usr/bin/env python3
+"""Pure cuDF/cuGraph reproducer for sparse string-ID graph build behavior.
+
+No PyGraphistry imports. This script is intended for issue filing and should run
+directly inside official RAPIDS base images.
+"""
+from __future__ import annotations
+
+import argparse
+import json
+import statistics
+import time
+from pathlib import Path
+from typing import Any, Dict, List
+
+
+GRAPH_CHOICES = [
+    "synthetic_offset",
+    "synthetic_string_offset",
+    "synthetic_string_gplus_shape",
+]
+
+GPLUS_SHAPE_VERTICES = 107_614
+
+
+def count_rows(df: Any) -> int:
+    return int(len(df))
+
+
+def expected_unique_nodes(edges: Any) -> int:
+    import cudf  # type: ignore
+
+    ids = cudf.concat([edges["src"], edges["dst"]], ignore_index=True)
+    return int(ids.nunique())
+
+
+def build_edges(graph_kind: str, edge_count: int):
+    import cudf  # type: ignore
+    import cupy as cp  # type: ignore
+
+    if graph_kind == "synthetic_string_gplus_shape":
+        start = 1_000_000
+        base = cudf.Series(cp.arange(edge_count, dtype=cp.int32) % cp.int32(GPLUS_SHAPE_VERTICES))
+        src = (base + start).astype("int32").astype("str")
+        dst = ((base + 1) % GPLUS_SHAPE_VERTICES + start).astype("int32").astype("str")
+        return cudf.DataFrame({"src": src, "dst": dst})
+
+    start = 1_000_000
+    src = cudf.Series(range(start, start + edge_count), dtype="int32")
+    dst = cudf.Series(range(start + 1, start + edge_count + 1), dtype="int32")
+
+    if graph_kind == "synthetic_offset":
+        return cudf.DataFrame({"src": src, "dst": dst})
+    if graph_kind == "synthetic_string_offset":
+        return cudf.DataFrame({"src": src.astype("str"), "dst": dst.astype("str")})
+
+    raise ValueError(f"Unsupported graph kind: {graph_kind}")
+
+
+def measure_once(edges: Any, *, store_transposed: bool) -> Dict[str, Any]:
+    import cugraph  # type: ignore
+
+    t0 = time.perf_counter()
+    G = cugraph.Graph(directed=True)
+    G.from_cudf_edgelist(
+        edges,
+        source="src",
+        destination="dst",
+        store_transposed=store_transposed,
+    )
+    t1 = time.perf_counter()
+    pr = cugraph.pagerank(G)
+    t2 = time.perf_counter()
+    return {
+        "build_s": t1 - t0,
+        "pagerank_s": t2 - t1,
+        "total_s": t2 - t0,
+        "graph_vertices": int(G.number_of_vertices()),
+        "pagerank_rows": int(len(pr)),
+    }
+
+
+def median(values: List[float]) -> float:
+    return float(statistics.median(values)) if values else 0.0
+
+
+def run_case(graph_kind: str, edge_count: int, *, store_transposed: bool, runs: int, warmup: int) -> Dict[str, Any]:
+    edges = build_edges(graph_kind, edge_count)
+
+    for _ in range(warmup):
+        measure_once(edges, store_transposed=store_transposed)
+
+    rows = [measure_once(edges, store_transposed=store_transposed) for _ in range(runs)]
+    first = rows[0]
+    expected_nodes = expected_unique_nodes(edges)
+
+    return {
+        "graph_kind": graph_kind,
+        "edge_count": count_rows(edges),
+        "expected_unique_nodes": expected_nodes,
+        "src_dtype": str(edges["src"].dtype),
+        "dst_dtype": str(edges["dst"].dtype),
+        "store_transposed": store_transposed,
+        "warmup_runs": warmup,
+        "benchmark_runs": runs,
+        "build_median_s": round(median([float(r["build_s"]) for r in rows]), 4),
+        "pagerank_median_s": round(median([float(r["pagerank_s"]) for r in rows]), 4),
+        "total_median_s": round(median([float(r["total_s"]) for r in rows]), 4),
+        "build_runs_s": [round(float(r["build_s"]), 4) for r in rows],
+        "pagerank_runs_s": [round(float(r["pagerank_s"]), 4) for r in rows],
+        "total_runs_s": [round(float(r["total_s"]), 4) for r in rows],
+        "graph_vertices": int(first["graph_vertices"]),
+        "pagerank_rows": int(first["pagerank_rows"]),
+        "expected_vertex_match": int(first["graph_vertices"]) == expected_nodes,
+    }
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--graph", choices=GRAPH_CHOICES, default="synthetic_string_gplus_shape")
+    parser.add_argument("--synthetic-edges", type=int, default=10_000_000)
+    parser.add_argument("--runs", type=int, default=3)
+    parser.add_argument("--warmup", type=int, default=1)
+    parser.add_argument("--store-transposed", action="store_true")
+    parser.add_argument("--output-json", type=Path, default=None)
+    return parser.parse_args()
+
+
+def main() -> None:
+    args = parse_args()
+    payload = run_case(
+        args.graph,
+        args.synthetic_edges,
+        store_transposed=args.store_transposed,
+        runs=args.runs,
+        warmup=args.warmup,
+    )
+    text = json.dumps(payload, indent=2, sort_keys=True)
+    print(text)
+    if args.output_json is not None:
+        args.output_json.parent.mkdir(parents=True, exist_ok=True)
+        args.output_json.write_text(text + "\n")
+
+
+if __name__ == "__main__":
+    main()