diff --git a/package.json b/package.json
--- a/package.json
+++ b/package.json
@@ -13,6 +13,7 @@ "build:viz": "bun build public/viz/viz-hydrate.ts --outfile public/viz/dist.js",
 		"build:ui": "bun build public/ui.ts --outfile public/ui.js",
 		"build:htmx": "cp node_modules/htmx.org/dist/htmx.min.js public/htmx.min.js",
 		"backfill": "bun run scripts/backfill.ts",
+		"export-contributors": "bun run scripts/export-contributors.ts",
 		"test": "bun test",
 		"lint": "biome check src/ public/ tests/",
 		"lint:fix": "biome check --write src/ public/ tests/",
diff --git a/scripts/export-contributors.ts b/scripts/export-contributors.ts
new file mode 100644
--- /dev/null
+++ b/scripts/export-contributors.ts
@@ -0,0 +1,10 @@
+#!/usr/bin/env bun
+
+// Print the contributor seed list. Newline-delimited, or --json for an array.
+// Pipe into backfill: bun run backfill $(bun run export-contributors)
+
+import { listContributors } from "../src/registry/index.ts";
+
+const json = process.argv.slice(2).includes("--json");
+const dids = listContributors();
+console.log(json ? JSON.stringify(dids) : dids.join("\n"));
diff --git a/tests/registry/export-contributors.test.ts b/tests/registry/export-contributors.test.ts
new file mode 100644
--- /dev/null
+++ b/tests/registry/export-contributors.test.ts
@@ -0,0 +1,55 @@
+import { Database } from "bun:sqlite";
+import { afterAll, beforeAll, describe, expect, test } from "bun:test";
+import { rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+
+const dbPath = join(tmpdir(), `lichen-registry-export-${Date.now()}.db`);
+
+beforeAll(() => {
+	const db = new Database(dbPath);
+	db.run(
+		`CREATE TABLE contributors (did TEXT PRIMARY KEY, first_seen TEXT NOT NULL, last_seen TEXT NOT NULL)`,
+	);
+	db.run(
+		`INSERT INTO contributors (did, first_seen, last_seen) VALUES
+		 ('did:plc:ccc','x','x'), ('did:plc:aaa','x','x'), ('did:plc:bbb','x','x')`,
+	);
+	db.close();
+});
+
+afterAll(() => {
+	for (const suffix of ["", "-shm", "-wal"]) {
+		rmSync(dbPath + suffix, { force: true });
+	}
+});
+
+async function runExport(args: string[]): Promise<string> {
+	const proc = Bun.spawn(["bun", "scripts/export-contributors.ts", ...args], {
+		env: { ...process.env, REGISTRY_DB_PATH: dbPath },
+		stdout: "pipe",
+	});
+	const out = await new Response(proc.stdout).text();
+	await proc.exited;
+	return out;
+}
+
+describe("export-contributors CLI", () => {
+	test("emits the distinct DID set, sorted, one per line", async () => {
+		const out = await runExport([]);
+		expect(out.trim().split("\n")).toEqual([
+			"did:plc:aaa",
+			"did:plc:bbb",
+			"did:plc:ccc",
+		]);
+	});
+
+	test("--json emits a sorted array", async () => {
+		const out = await runExport(["--json"]);
+		expect(JSON.parse(out)).toEqual([
+			"did:plc:aaa",
+			"did:plc:bbb",
+			"did:plc:ccc",
+		]);
+	});
+});