diff --git a/scripts/backfill-graph.ts b/scripts/backfill-graph.ts
new file mode 100644
index 0000000..194addc
--- /dev/null
+++ b/scripts/backfill-graph.ts
@@ -0,0 +1,36 @@
+/**
+ * One-time backfill: wipe the legacy ledgers and re-extract every chat with
+ * the redesigned pipeline (vision §1, commit b07c907). Run from the master
+ * tree only — data never crosses trees:
+ *
+ *   npx tsx --env-file=.env.local scripts/backfill-graph.ts
+ */
+import { chatStore } from "../src/store/chats.ts";
+import { graphStore } from "../src/store/graph.ts";
+import { createExtractionPipeline } from "../src/agent/subagents/extraction.ts";
+import { getGraph } from "../src/core/graph.ts";
+
+async function main() {
+	const only = process.argv[2]; // optional: extract just one chat id
+	const chats = only ? chatStore.listChats().filter((c) => c.id === only) : chatStore.listChats();
+	console.log(`[backfill] ${chats.length} chats to extract`);
+	const pipeline = createExtractionPipeline({ chatStore, graphStore });
+	for (const chat of chats) {
+		const t0 = Date.now();
+		try {
+			const stats = await pipeline.runExtraction(chat.id);
+			console.log(
+				`[backfill] ${chat.id} (${chat.title.slice(0, 40)}): ` +
+					`${stats.nodes} nodes, ${stats.edges} edges, ${stats.events} events in ${((Date.now() - t0) / 1000).toFixed(1)}s`,
+			);
+		} catch (err) {
+			console.error(`[backfill] ${chat.id} FAILED:`, err);
+		}
+	}
+	const graph = getGraph(graphStore);
+	console.log(
+		`[backfill] done: ${graph.nodes.length} nodes, ${graph.edges.length} edges, ${graph.events.length} events`,
+	);
+}
+
+main();