diff --git a/package.json b/package.json
index 21b975c3bb..34ffc553dc 100644
--- a/package.json
+++ b/package.json
@@ -71,6 +71,7 @@
     "ui:version-audit": "node --experimental-strip-types scripts/check-ui-mcp-version-copy.ts",
     "ui:version-audit:sync": "node --experimental-strip-types scripts/check-ui-mcp-version-copy.ts --write",
     "docs:drift-check": "node --experimental-strip-types scripts/check-docs-drift.ts",
+    "roadmap:drift-check": "node --experimental-strip-types scripts/check-roadmap-issue-drift.ts",
     "branding-drift:check": "node --experimental-strip-types scripts/check-branding-drift.ts",
     "branding-drift:update": "node --experimental-strip-types scripts/check-branding-drift.ts --update",
     "manifest:drift-check": "tsx scripts/check-manifest-drift.ts",
diff --git a/scripts/check-roadmap-issue-drift.ts b/scripts/check-roadmap-issue-drift.ts
new file mode 100644
index 0000000000..cdd1db09ff
--- /dev/null
+++ b/scripts/check-roadmap-issue-drift.ts
@@ -0,0 +1,164 @@
+#!/usr/bin/env node
+// Detects when /roadmap still presents phase epics as active/upcoming ("shipping-soon" / "planned")
+// while the linked GitHub issues are already closed as completed. That drift silently persisted on the
+// public page after phases #233-#238 shipped (#8390). Local/manual (or future scheduled) check only —
+// needs live GitHub API access, so it is deliberately NOT wired into `test:ci`.
+
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+import { pathToFileURL } from "node:url";
+
+export const DEFAULT_ROADMAP_SOURCE = "apps/loopover-ui/src/routes/roadmap.tsx";
+export const DEFAULT_OWNER = "JSONbored";
+export const DEFAULT_REPO = "loopover";
+
+/** Statuses that visually present the item as still-active / upcoming work on /roadmap. */
+export const ACTIVE_ROADMAP_STATUSES = new Set<string>(["shipping-soon", "planned"]);
+
+export type RoadmapItemStatus = "shipping-soon" | "planned" | "exploring";
+
+export type RoadmapItemRef = {
+  status: RoadmapItemStatus;
+  issue: number;
+};
+
+export type GithubIssueState = {
+  state: string;
+  stateReason: string | null;
+};
+
+// Deliberately `any`-shaped like check-stuck-required-checks: callers read issue fields off the
+// resolved JSON without a runtime schema, and typing this `unknown` would only force casts.
+export type GithubApi = (path: string, options?: { method?: string; headers?: Record<string, string> }) => Promise<any>;
+
+export function makeGithubApi(token: string): GithubApi {
+  return async function githubApi(path, options = {}) {
+    const response = await fetch(`https://api.github.com${path}`, {
+      ...options,
+      headers: {
+        Authorization: `Bearer ${token}`,
+        Accept: "application/vnd.github+json",
+        "X-GitHub-Api-Version": "2022-11-28",
+        ...options.headers,
+      },
+    });
+    if (!response.ok) {
+      throw new Error(`GitHub API error ${response.status} on ${path}: ${await response.text()}`);
+    }
+    return response.status === 204 ? null : response.json();
+  };
+}
+
+/** Parse `ROADMAP_ITEMS` object literals from `roadmap.tsx` source text (status + issue only). */
+export function parseRoadmapItems(sourceText: string): RoadmapItemRef[] {
+  const catalogMatch = /const\s+ROADMAP_ITEMS[^=]*=\s*\[([\s\S]*?)\];/.exec(sourceText);
+  if (!catalogMatch) throw new Error("ROADMAP_ITEMS array not found in roadmap source");
+  const body = catalogMatch[1]!;
+  const items: RoadmapItemRef[] = [];
+  for (const objectMatch of body.matchAll(/\{([^{}]+)\}/g)) {
+    const objectBody = objectMatch[1]!;
+    const status = /status:\s*"(shipping-soon|planned|exploring)"/.exec(objectBody)?.[1] as RoadmapItemStatus | undefined;
+    const issueRaw = /issue:\s*(\d+)/.exec(objectBody)?.[1];
+    if (!status || !issueRaw) continue;
+    items.push({ status, issue: Number(issueRaw) });
+  }
+  if (items.length === 0) throw new Error("ROADMAP_ITEMS contained no parseable { status, issue } entries");
+  return items;
+}
+
+/**
+ * Pure drift rule (#8390): fail only when the page presents the item as active/upcoming
+ * (`shipping-soon` / `planned`) but GitHub says the issue is closed as completed.
+ * `exploring` items are never flagged here — abandoned "later" ideas (e.g. NOT_PLANNED) and
+ * finished exploring work are both content judgment calls outside this mechanical check.
+ */
+export function isStaleActiveRoadmapPresentation(input: {
+  status: string;
+  issueState: string;
+  issueStateReason: string | null | undefined;
+}): boolean {
+  if (!ACTIVE_ROADMAP_STATUSES.has(input.status)) return false;
+  if (input.issueState.toLowerCase() !== "closed") return false;
+  return (input.issueStateReason ?? "").toUpperCase() === "COMPLETED";
+}
+
+export type StaleRoadmapItem = RoadmapItemRef & GithubIssueState;
+
+export async function findStaleRoadmapItems({
+  items,
+  githubApi,
+  owner,
+  repo,
+}: {
+  items: RoadmapItemRef[];
+  githubApi: GithubApi;
+  owner: string;
+  repo: string;
+}): Promise<StaleRoadmapItem[]> {
+  const stale: StaleRoadmapItem[] = [];
+  for (const item of items) {
+    const issue = await githubApi(`/repos/${owner}/${repo}/issues/${item.issue}`);
+    const state = String(issue.state ?? "");
+    const stateReason = issue.state_reason == null ? null : String(issue.state_reason);
+    if (isStaleActiveRoadmapPresentation({ status: item.status, issueState: state, issueStateReason: stateReason })) {
+      stale.push({ ...item, state, stateReason });
+    }
+  }
+  return stale;
+}
+
+export function formatStaleRoadmapFailures(stale: StaleRoadmapItem[]): string[] {
+  return stale.map(
+    (item) =>
+      `#${item.issue} (status=${item.status}): GitHub state=${item.state} stateReason=${item.stateReason ?? "null"} — still presented as active/upcoming on /roadmap while closed as completed`,
+  );
+}
+
+export async function checkRoadmapIssueDrift({
+  roadmapSourceText,
+  githubApi,
+  owner = DEFAULT_OWNER,
+  repo = DEFAULT_REPO,
+}: {
+  roadmapSourceText: string;
+  githubApi: GithubApi;
+  owner?: string;
+  repo?: string;
+}): Promise<string[]> {
+  const items = parseRoadmapItems(roadmapSourceText);
+  const stale = await findStaleRoadmapItems({ items, githubApi, owner, repo });
+  return formatStaleRoadmapFailures(stale);
+}
+
+async function main(): Promise<void> {
+  const root = process.cwd();
+  const sourcePath = join(root, DEFAULT_ROADMAP_SOURCE);
+  const roadmapSourceText = readFileSync(sourcePath, "utf8");
+
+  const repoEnv = process.env.GITHUB_REPOSITORY;
+  const [owner, repo] = repoEnv?.includes("/") ? repoEnv.split("/") : [DEFAULT_OWNER, DEFAULT_REPO];
+  const token = process.env.GITHUB_TOKEN ?? process.env.GH_TOKEN;
+  if (!token) throw new Error("GITHUB_TOKEN (or GH_TOKEN) is required for roadmap:drift-check");
+
+  const failures = await checkRoadmapIssueDrift({
+    roadmapSourceText,
+    githubApi: makeGithubApi(token),
+    owner: owner!,
+    repo: repo!,
+  });
+
+  if (failures.length > 0) {
+    console.error(`Roadmap issue-drift check found ${failures.length} stale active/upcoming item(s):`);
+    for (const failure of failures) console.error(`  ${failure}`);
+    console.error(
+      "Update ROADMAP_ITEMS in apps/loopover-ui/src/routes/roadmap.tsx so active columns only reference open (or not-yet-done) phase issues.",
+    );
+    process.exit(1);
+  }
+
+  console.log("Roadmap issue-drift check ok: no active/upcoming ROADMAP_ITEMS reference a completed closed issue.");
+}
+
+if (import.meta.url === pathToFileURL(process.argv[1] ?? "").href) {
+  await main();
+}
diff --git a/test/unit/check-roadmap-issue-drift-script.test.ts b/test/unit/check-roadmap-issue-drift-script.test.ts
new file mode 100644
index 0000000000..18f07d81b0
--- /dev/null
+++ b/test/unit/check-roadmap-issue-drift-script.test.ts
@@ -0,0 +1,178 @@
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+import { describe, expect, it } from "vitest";
+
+import {
+  ACTIVE_ROADMAP_STATUSES,
+  checkRoadmapIssueDrift,
+  findStaleRoadmapItems,
+  formatStaleRoadmapFailures,
+  isStaleActiveRoadmapPresentation,
+  parseRoadmapItems,
+  type GithubApi,
+  type RoadmapItemRef,
+} from "../../scripts/check-roadmap-issue-drift.js";
+
+// (#8390) Pure drift rule + parser coverage for the roadmap issue-drift check. Live GitHub is injected;
+// these tests never hit the network.
+
+describe("isStaleActiveRoadmapPresentation (#8390)", () => {
+  it.each([
+    {
+      name: "shipping-soon + closed completed → stale",
+      input: { status: "shipping-soon", issueState: "closed", issueStateReason: "completed" },
+      expected: true,
+    },
+    {
+      name: "planned + closed COMPLETED (GraphQL casing) → stale",
+      input: { status: "planned", issueState: "CLOSED", issueStateReason: "COMPLETED" },
+      expected: true,
+    },
+    {
+      name: "shipping-soon + open → not stale",
+      input: { status: "shipping-soon", issueState: "open", issueStateReason: null },
+      expected: false,
+    },
+    {
+      name: "planned + closed not_planned → not stale (wrong reason)",
+      input: { status: "planned", issueState: "closed", issueStateReason: "not_planned" },
+      expected: false,
+    },
+    {
+      name: "planned + closed with missing reason → not stale",
+      input: { status: "planned", issueState: "closed", issueStateReason: null },
+      expected: false,
+    },
+    {
+      name: "exploring + closed completed → not stale (only active columns are gated)",
+      input: { status: "exploring", issueState: "closed", issueStateReason: "completed" },
+      expected: false,
+    },
+    {
+      name: "exploring + closed not_planned → not stale",
+      input: { status: "exploring", issueState: "closed", issueStateReason: "not_planned" },
+      expected: false,
+    },
+  ])("$name", ({ input, expected }) => {
+    expect(isStaleActiveRoadmapPresentation(input)).toBe(expected);
+  });
+
+  it("treats only shipping-soon and planned as active presentation statuses", () => {
+    expect([...ACTIVE_ROADMAP_STATUSES].sort()).toEqual(["planned", "shipping-soon"]);
+  });
+});
+
+describe("parseRoadmapItems (#8390)", () => {
+  it("extracts status + issue from a ROADMAP_ITEMS array literal", () => {
+    const source = `
+const ROADMAP_ITEMS: Array<{ status: string; issue: number }> = [
+  {
+    title: "Phase 0",
+    status: "shipping-soon",
+    issue: 233,
+    description: "x",
+  },
+  {
+    title: "Phase 2",
+    status: "planned",
+    issue: 235,
+    description: "y",
+  },
+  {
+    title: "Phase 4",
+    status: "exploring",
+    issue: 237,
+    description: "z",
+  },
+];
+`;
+    expect(parseRoadmapItems(source)).toEqual([
+      { status: "shipping-soon", issue: 233 },
+      { status: "planned", issue: 235 },
+      { status: "exploring", issue: 237 },
+    ]);
+  });
+
+  it("throws when ROADMAP_ITEMS is missing or empty of parseable entries", () => {
+    expect(() => parseRoadmapItems("const OTHER = [];")).toThrow(/ROADMAP_ITEMS array not found/);
+    expect(() => parseRoadmapItems("const ROADMAP_ITEMS = [];")).toThrow(/no parseable/);
+  });
+
+  it("parses the real apps/loopover-ui roadmap source", () => {
+    const source = readFileSync(join(process.cwd(), "apps/loopover-ui/src/routes/roadmap.tsx"), "utf8");
+    const items = parseRoadmapItems(source);
+    expect(items.length).toBeGreaterThanOrEqual(6);
+    expect(items.every((item) => typeof item.issue === "number" && item.issue > 0)).toBe(true);
+    expect(items.some((item) => ACTIVE_ROADMAP_STATUSES.has(item.status))).toBe(true);
+  });
+});
+
+describe("findStaleRoadmapItems / checkRoadmapIssueDrift (#8390)", () => {
+  const items: RoadmapItemRef[] = [
+    { status: "shipping-soon", issue: 233 },
+    { status: "planned", issue: 235 },
+    { status: "exploring", issue: 237 },
+  ];
+
+  function issueApi(byNumber: Record<number, { state: string; state_reason: string | null }>): GithubApi {
+    return async (path: string) => {
+      const match = /\/issues\/(\d+)$/.exec(path);
+      if (!match) throw new Error(`unexpected path: ${path}`);
+      const issue = byNumber[Number(match[1])];
+      if (!issue) throw new Error(`unexpected issue: ${match[1]}`);
+      return issue;
+    };
+  }
+
+  it("returns stale active items and skips exploring even when completed", async () => {
+    const stale = await findStaleRoadmapItems({
+      items,
+      owner: "JSONbored",
+      repo: "loopover",
+      githubApi: issueApi({
+        233: { state: "closed", state_reason: "completed" },
+        235: { state: "open", state_reason: null },
+        237: { state: "closed", state_reason: "completed" },
+      }),
+    });
+    expect(stale).toEqual([{ status: "shipping-soon", issue: 233, state: "closed", stateReason: "completed" }]);
+    expect(formatStaleRoadmapFailures(stale)[0]).toContain("#233");
+    expect(formatStaleRoadmapFailures(stale)[0]).toContain("stateReason=completed");
+  });
+
+  it("passes when every active item is still open", async () => {
+    const failures = await checkRoadmapIssueDrift({
+      roadmapSourceText: `
+const ROADMAP_ITEMS = [
+  { status: "shipping-soon", issue: 1 },
+  { status: "planned", issue: 2 },
+  { status: "exploring", issue: 3 },
+];
+`,
+      githubApi: issueApi({
+        1: { state: "open", state_reason: null },
+        2: { state: "open", state_reason: null },
+        3: { state: "closed", state_reason: "completed" },
+      }),
+    });
+    expect(failures).toEqual([]);
+  });
+
+  it("fails with clear messages when planned/shipping-soon issues are completed", async () => {
+    const failures = await checkRoadmapIssueDrift({
+      roadmapSourceText: `
+const ROADMAP_ITEMS = [
+  { status: "shipping-soon", issue: 10 },
+  { status: "planned", issue: 11 },
+];
+`,
+      githubApi: issueApi({
+        10: { state: "closed", state_reason: "completed" },
+        11: { state: "closed", state_reason: "completed" },
+      }),
+    });
+    expect(failures).toHaveLength(2);
+    expect(failures[0]).toMatch(/#10.*shipping-soon/);
+    expect(failures[1]).toMatch(/#11.*planned/);
+  });
+});