diff --git a/src/app/api/__tests__/module-route-gate-inventory.test.ts b/src/app/api/__tests__/module-route-gate-inventory.test.ts
index 5132e2a40..4eb497233 100644
--- a/src/app/api/__tests__/module-route-gate-inventory.test.ts
+++ b/src/app/api/__tests__/module-route-gate-inventory.test.ts
@@ -1,4 +1,4 @@
-import { readdirSync, readFileSync, statSync } from "node:fs";
+import { existsSync, readdirSync, readFileSync, statSync } from "node:fs";
 import { join, relative, resolve } from "node:path";
 
 import { describe, expect, it } from "vitest";
@@ -38,13 +38,7 @@ import { MODULE_KEYS, type ModuleKey } from "@/lib/modules/registry";
  *                   `coach-route-gate-inventory.test.ts`; listed here so
  *                   coach-bearing routes are not flagged as ungated.
  *
- *   3. BUILDER-GATED — the route delegates its whole payload to an
- *      aggregator that resolves `resolveModuleMap(userId)` once and
- *      excludes disabled-module sections/resources from the build
- *      (`collectDoctorReportData`, `loadFhirContext`). The exclusion is
- *      structural at the builder, so the route carries no per-key call.
- *
- *   4. EXEMPT — an explicit, COMMENTED allowlist of routes that serve a
+ *   3. EXEMPT — an explicit, COMMENTED allowlist of routes that serve a
  *      toggleable domain but are deliberately NOT gated, each with the
  *      reason at the entry. The two reasons in play:
  *        - DATA LAYER: raw CRUD over the domain's own rows. Writing or
@@ -56,9 +50,30 @@ import { MODULE_KEYS, type ModuleKey } from "@/lib/modules/registry";
  *        - INFRA / UI-ONLY: settings, availability probes, and the static
  *          FHIR CapabilityStatement carry no module data.
  *
- * Anything that doesn't fit one of the four buckets is an orphan and
+ * Anything that doesn't fit one of the three buckets is an orphan and
  * fails the test BY NAME so the fix is one search-and-add: gate the route
  * or move it onto the EXEMPT allowlist with a documented reason.
+ *
+ * WHAT THIS TEST DOES NOT PROVE, AND WHO PROVES IT
+ * -----------------------------------------------
+ * This file is a DISCOVERY test: it proves no route escapes classification.
+ * It cannot prove a gate actually refuses, because it only reads source text.
+ *
+ * That distinction used to be blurred. A fourth "BUILDER-GATED" bucket
+ * accepted the mere MENTION of an aggregator's name (`loadFhirContext`,
+ * `collectDoctorReportData`) as proof that the route was gated. It was not
+ * proof of anything: `loadFhirContext` filtered per-domain modules but never
+ * evaluated `doctorReport`, so all five `/api/fhir/*` data routes sat in a
+ * green bucket while serving the whole record — including the decrypted
+ * insurance number — to an account that had the doctor-report module off.
+ * The bucket is gone. A route is now only counted as gated when it CALLS a
+ * gate, and `REQUIRED_TREE_MODULE` below pins which key it must name.
+ *
+ * The behaviour itself — a disabled module actually producing a 403 or an
+ * omission — is proven by the per-surface tests listed in
+ * `BEHAVIOURAL_GATE_TESTS`. This test asserts those files still exist, so
+ * deleting the behavioural coverage fails here with a pointer to what was
+ * lost rather than silently leaving only a text-match behind.
  */
 
 /**
@@ -99,9 +114,10 @@ const MODULE_ROUTE_TREES: ReadonlyArray<string> = [
   "src/app/api/medications",
   // v1.18.0 B3 — the legacy `/api/doctor-report` tree (JSON + server-PDF +
   // availability probe) was orphaned dead code (no production caller) and
-  // removed. The live doctor-report / FHIR surface is `/api/export/health-record`,
-  // which gates on the `doctorReport` module directly AND through the
-  // `collectDoctorReportData` builder.
+  // removed. The doctor-report surface is `/api/export/health-record` plus
+  // the FHIR REST face below; both gate on `doctorReport` directly. The FHIR
+  // routes previously relied on the removed builder-mention bucket and were
+  // in practice ungated — see the header note.
   "src/app/api/fhir",
   // v1.18.0 (B2) — the AI-narrative insights tree. Every status / cards /
   // correlations / derived / narrative / pregenerate / rhythm-events route
@@ -273,12 +289,55 @@ const COACH_GATE_NEEDLE = 'requireAssistantSurface("coach")';
 // `requireCycleEnabled`. Recognised as a delegated gate so illness routes
 // are not flagged as ungated.
 const ILLNESS_GATE_NEEDLE = "requireIllnessEnabled(";
-// Builder aggregators that resolve `resolveModuleMap` once and exclude
-// disabled-module sections/resources at the build boundary.
-const BUILDER_GATE_NEEDLES: ReadonlyArray<string> = [
-  "collectDoctorReportData",
-  "loadFhirContext",
-];
+
+/**
+ * Trees whose routes must gate on ONE specific module key. Naming the key
+ * here means a future route in the tree cannot satisfy the inventory by
+ * gating on some other, more permissive module — the failure mode that a
+ * generic "is there any gate?" check cannot see.
+ *
+ * `/api/fhir` is the entry that matters: every data route there serves the
+ * whole-record doctor-report aggregate, so `doctorReport` is the only
+ * correct key.
+ */
+const REQUIRED_TREE_MODULE: Readonly<Record<string, ModuleKey>> = {
+  "src/app/api/fhir": "doctorReport",
+};
+
+/**
+ * Surfaces whose module behaviour is proven by a real behavioural test
+ * (module off ⇒ 403 or omission; module on ⇒ served). Listed so that
+ * deleting the proof fails the inventory instead of quietly downgrading the
+ * guarantee back to a text match.
+ *
+ * The three aggregate surfaces below are the ones that re-served per-domain
+ * data ungated: two of them (`/api/sync/changes`, `/api/dashboard/summary`)
+ * are cross-domain feeds that live outside `MODULE_ROUTE_TREES` entirely, so
+ * without this list nothing in the inventory would notice them at all.
+ */
+const BEHAVIOURAL_GATE_TESTS: ReadonlyArray<{ path: string; proves: string }> =
+  [
+    {
+      path: "src/app/api/fhir/__tests__/module-gate.test.ts",
+      proves:
+        "every /api/fhir data route 403s with module.disabled when doctorReport is off",
+    },
+    {
+      path: "src/lib/fhir/__tests__/rest-module-backstop.test.ts",
+      proves:
+        "loadFhirContext itself refuses to assemble the record when doctorReport is off",
+    },
+    {
+      path: "src/app/api/sync/changes/__tests__/module-gate.test.ts",
+      proves:
+        "the sync delta feed omits cycleDays/cycles (and never queries them) when cycle is off",
+    },
+    {
+      path: "src/app/api/dashboard/summary/__tests__/module-gate.test.ts",
+      proves:
+        "the dashboard summary drops disabled-module metric cards while core vitals still ship",
+    },
+  ];
 
 /**
  * True when the file contains the needle on a line that is NOT a pure
@@ -373,7 +432,7 @@ describe("module API route gate inventory", () => {
     }
   });
 
-  it("every toggleable-module route is gated, delegated, builder-gated, or explicitly exempt", () => {
+  it("every toggleable-module route is gated, delegated, or explicitly exempt", () => {
     const routes = findAllModuleRouteFiles();
     expect(routes.length).toBeGreaterThan(0);
 
@@ -387,15 +446,16 @@ describe("module API route gate inventory", () => {
       if (fileHasCall(text, CYCLE_GATE_NEEDLE)) continue;
       if (fileHasCall(text, COACH_GATE_NEEDLE)) continue;
       if (fileHasCall(text, ILLNESS_GATE_NEEDLE)) continue;
-      if (BUILDER_GATE_NEEDLES.some((n) => fileHasCall(text, n))) continue;
 
       if (exempt.has(path)) continue;
 
       orphans.push({
         path,
         reason:
-          'no module gate found — add requireModuleEnabled("<key>"), a delegated gate, ' +
-          "a module-aware builder, or move the route onto EXEMPT_ROUTES with a documented reason",
+          'no module gate found — add requireModuleEnabled("<key>") or a delegated gate, ' +
+          "or move the route onto EXEMPT_ROUTES with a documented reason. " +
+          "Importing a module-aware builder is NOT a gate: a builder can filter some " +
+          "modules and never evaluate yours.",
       });
     }
 
@@ -432,6 +492,55 @@ describe("module API route gate inventory", () => {
     ).toEqual([]);
   });
 
+  it("routes in a key-pinned tree gate on that tree's module key", () => {
+    // A generic "is there any gate?" check cannot tell `doctorReport` from
+    // some other, more permissive key. Where a whole tree serves exactly one
+    // module, name it.
+    const wrong: Array<{ path: string; found: string[] }> = [];
+
+    for (const [tree, requiredKey] of Object.entries(REQUIRED_TREE_MODULE)) {
+      for (const path of findRouteFiles(tree)) {
+        if (EXEMPT_ROUTES.includes(path)) continue;
+        const text = readFileSync(resolve(repoRoot, path), "utf8");
+        const { keys } = extractModuleKeys(text);
+        if (!keys.has(requiredKey)) {
+          wrong.push({ path, found: [...keys] });
+        }
+      }
+    }
+
+    expect(
+      wrong,
+      [
+        "Routes that must gate on their tree's module key but do not:",
+        ...wrong.map(
+          (w) =>
+            `  - ${w.path}: found [${w.found.join(", ") || "no literal key"}]`,
+        ),
+      ].join("\n"),
+    ).toEqual([]);
+  });
+
+  it("the behavioural gate tests that prove refusal still exist", () => {
+    // This inventory only reads source text. The listed files are what
+    // actually exercise a disabled module end to end; losing one silently
+    // downgrades the guarantee back to a text match, which is precisely the
+    // failure this test was rewritten to prevent.
+    const missing = BEHAVIOURAL_GATE_TESTS.filter(
+      (t) => !existsSync(resolve(repoRoot, t.path)),
+    );
+
+    expect(
+      missing,
+      [
+        "Behavioural module-gate coverage has gone missing.",
+        "This inventory cannot prove a gate refuses — these tests do:",
+        ...missing.map((m) => `  - ${m.path}\n      proves: ${m.proves}`),
+        "Restore the file, or drop the entry and say what replaces it.",
+      ].join("\n"),
+    ).toEqual([]);
+  });
+
   it("EXEMPT_ROUTES does not reference deleted route files", () => {
     const known = new Set(findAllModuleRouteFiles());
     const stale = EXEMPT_ROUTES.filter((p) => !known.has(p));
@@ -457,8 +566,7 @@ describe("module API route gate inventory", () => {
         fileHasCall(text, MODULE_GATE_NEEDLE) ||
         fileHasCall(text, CYCLE_GATE_NEEDLE) ||
         fileHasCall(text, COACH_GATE_NEEDLE) ||
-        fileHasCall(text, ILLNESS_GATE_NEEDLE) ||
-        BUILDER_GATE_NEEDLES.some((n) => fileHasCall(text, n))
+        fileHasCall(text, ILLNESS_GATE_NEEDLE)
       ) {
         stillGated.push(path);
       }
diff --git a/src/app/api/dashboard/summary/__tests__/module-gate.test.ts b/src/app/api/dashboard/summary/__tests__/module-gate.test.ts
new file mode 100644
index 000000000..577966bf1
--- /dev/null
+++ b/src/app/api/dashboard/summary/__tests__/module-gate.test.ts
@@ -0,0 +1,212 @@
+/**
+ * `GET /api/dashboard/summary` — module gate.
+ *
+ * This route builds its own payload instead of going through
+ * `readDashboardSnapshotCached`, so it never picked up the gate the shared
+ * snapshot builder applies: it emitted glucose and sleep cards on data
+ * presence alone while `/api/dashboard/snapshot` correctly withheld them for
+ * the very same account.
+ *
+ * OMIT, not 403 — the payload spans ten metric cards across several domains,
+ * and blanking an iOS dashboard because one module is off would be the wrong
+ * trade. Core vitals must keep flowing.
+ *
+ * Behavioural: the assertions read the emitted card list, so reverting the
+ * filter in the route turns them red.
+ */
+import { describe, it, expect, vi, beforeEach } from "vitest";
+
+vi.mock("@/lib/auth/session", () => ({ getSession: vi.fn() }));
+vi.mock("@/lib/logging/transports", () => ({ emitIfSampled: vi.fn() }));
+vi.mock("@/lib/db-compat", () => ({
+  ensureDbCompatibility: vi.fn().mockResolvedValue(undefined),
+}));
+// The gate resolver runs for real; only its data sources are stubbed, so the
+// module state is driven the way production drives it.
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    user: { findUnique: vi.fn() },
+    cycleProfile: { findUnique: vi.fn() },
+  },
+}));
+vi.mock("@/lib/modules/operator-availability", async (importOriginal) => {
+  const actual =
+    await importOriginal<
+      typeof import("@/lib/modules/operator-availability")
+    >();
+  return { ...actual, getOperatorModuleAvailability: vi.fn() };
+});
+vi.mock("@/lib/feature-flags", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@/lib/feature-flags")>();
+  return { ...actual, getAssistantFlags: vi.fn() };
+});
+// The heavy builder is stubbed: this test pins the GATE, not the aggregate
+// (which has its own coverage). It returns one card per emitted kind.
+vi.mock("@/lib/cache/server-cache", () => ({
+  caches: { analytics: {} },
+  cachedSwr: vi.fn(),
+}));
+vi.mock("next/headers", () => ({
+  headers: vi.fn(async () => ({ get: () => null })),
+  cookies: vi.fn(async () => ({
+    get: () => undefined,
+    set: () => {},
+    delete: () => {},
+  })),
+}));
+
+import { GET } from "../route";
+import { getSession } from "@/lib/auth/session";
+import { cachedSwr } from "@/lib/cache/server-cache";
+import { MODULE_KEYS } from "@/lib/modules/gate";
+import { getOperatorModuleAvailability } from "@/lib/modules/operator-availability";
+import { getAssistantFlags } from "@/lib/feature-flags";
+import { prisma } from "@/lib/db";
+
+const SESSION_OK = {
+  session: { id: "sess-1", expiresAt: new Date(Date.now() + 3_600_000) },
+  user: {
+    id: "user-1",
+    username: "tester",
+    role: "USER" as const,
+    displayName: null,
+    locale: "en",
+    timezone: "UTC",
+  },
+};
+
+/** Every card kind the builder can emit, one card each. */
+const ALL_KINDS = [
+  "weight",
+  "bloodPressure",
+  "pulse",
+  "bodyFat",
+  "glucose",
+  "sleep",
+  "steps",
+  "totalBodyWater",
+  "boneMass",
+  "oxygenSaturation",
+] as const;
+
+function card(kind: string) {
+  return {
+    id: kind,
+    kind,
+    titleKey: `dashboard.metric.title.${kind}`,
+    latestValue: 1,
+    secondaryValue: null,
+    unitKey: `dashboard.metric.unit.${kind}`,
+    unit: null,
+    sleepStages: null,
+    sleepSourceDiscrepancy: null,
+    trend: "flat",
+    sparkline: [1],
+    updatedAt: new Date().toISOString(),
+    allTimeCount: 5,
+    lastSeenAt: new Date().toISOString(),
+  };
+}
+
+/** Drive the real gate through the persisted disabled-allowlist. */
+function setDisabledModules(disabled: string[]): void {
+  vi.mocked(prisma.user.findUnique).mockResolvedValue({
+    gender: null,
+    disableCoach: false,
+    modulePreferencesJson: Object.fromEntries(disabled.map((k) => [k, false])),
+  } as never);
+  vi.mocked(prisma.cycleProfile.findUnique).mockResolvedValue(null as never);
+}
+
+async function emittedKinds(): Promise<string[]> {
+  const res = await GET();
+  expect(res.status).toBe(200);
+  const body = (await res.json()) as {
+    data: { metrics: Array<{ kind: string }> };
+  };
+  return body.data.metrics.map((m) => m.kind);
+}
+
+beforeEach(() => {
+  vi.resetAllMocks();
+  vi.mocked(getSession).mockResolvedValue(SESSION_OK as never);
+  vi.mocked(getOperatorModuleAvailability).mockResolvedValue(
+    Object.fromEntries(MODULE_KEYS.map((k) => [k, true])) as never,
+  );
+  vi.mocked(getAssistantFlags).mockResolvedValue({ coach: true } as never);
+  vi.mocked(cachedSwr).mockImplementation((async () => ({
+    greeting: { salutation: "hi", date: new Date().toISOString() },
+    streak: { currentDays: 0, longest: 0, label: "" },
+    compliance: { scheduledToday: 0, takenToday: 0 },
+    highlightInsight: null,
+    metrics: ALL_KINDS.map(card),
+    sleepRhythm: null,
+    lastUpdated: new Date().toISOString(),
+  })) as never);
+});
+
+describe("GET /api/dashboard/summary — module gate", () => {
+  it("emits every card when no module is disabled", async () => {
+    setDisabledModules([]);
+    expect(await emittedKinds()).toEqual([...ALL_KINDS]);
+  });
+
+  it("drops the glucose card when the glucose module is off", async () => {
+    setDisabledModules(["glucose"]);
+    const kinds = await emittedKinds();
+
+    expect(kinds).not.toContain("glucose");
+    // Everything else survives — proves an omission, not a refusal.
+    expect(kinds).toContain("weight");
+    expect(kinds).toContain("sleep");
+    expect(kinds).toHaveLength(ALL_KINDS.length - 1);
+  });
+
+  it("drops the sleep card when the sleep module is off", async () => {
+    setDisabledModules(["sleep"]);
+    const kinds = await emittedKinds();
+
+    expect(kinds).not.toContain("sleep");
+    expect(kinds).toContain("glucose");
+    expect(kinds).toHaveLength(ALL_KINDS.length - 1);
+  });
+
+  it("drops both when both modules are off", async () => {
+    setDisabledModules(["glucose", "sleep"]);
+    const kinds = await emittedKinds();
+
+    expect(kinds).not.toContain("glucose");
+    expect(kinds).not.toContain("sleep");
+    expect(kinds).toHaveLength(ALL_KINDS.length - 2);
+  });
+
+  it("never drops a core vital, whatever is disabled", async () => {
+    // Core metrics carry no SUMMARY_TYPE_MODULE entry and must always ship.
+    setDisabledModules([...MODULE_KEYS]);
+    const kinds = await emittedKinds();
+
+    for (const core of [
+      "weight",
+      "bloodPressure",
+      "pulse",
+      "bodyFat",
+      "steps",
+      "totalBodyWater",
+      "boneMass",
+      "oxygenSaturation",
+    ]) {
+      expect(kinds).toContain(core);
+    }
+  });
+
+  it("gates the cached body, so a toggle takes effect on the next request", async () => {
+    // The analytics LRU is not evicted by a module toggle. The filter must
+    // therefore run on the way out, not inside the cached build.
+    setDisabledModules([]);
+    expect(await emittedKinds()).toContain("glucose");
+
+    // Same cached body, module now off.
+    setDisabledModules(["glucose"]);
+    expect(await emittedKinds()).not.toContain("glucose");
+  });
+});
diff --git a/src/app/api/dashboard/summary/__tests__/route.test.ts b/src/app/api/dashboard/summary/__tests__/route.test.ts
index 466b89dc4..3bf6040e0 100644
--- a/src/app/api/dashboard/summary/__tests__/route.test.ts
+++ b/src/app/api/dashboard/summary/__tests__/route.test.ts
@@ -1,6 +1,19 @@
 import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
 import { NextRequest } from "next/server";
 
+// Every module is on for the aggregate assertions below; the gate's own
+// behaviour (which cards a disabled module drops) is pinned in the sibling
+// `module-gate.test.ts`.
+vi.mock("@/lib/modules/gate", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@/lib/modules/gate")>();
+  return {
+    ...actual,
+    resolveModuleMap: vi.fn(async () =>
+      Object.fromEntries(actual.MODULE_KEYS.map((k) => [k, true])),
+    ),
+  };
+});
+
 vi.mock("@/lib/db", () => ({
   prisma: {
     // v1.11.4 — `findMany` reads the raw per-stage SLEEP_DURATION rows for
diff --git a/src/app/api/dashboard/summary/route.ts b/src/app/api/dashboard/summary/route.ts
index dbf4490f2..00b399f98 100644
--- a/src/app/api/dashboard/summary/route.ts
+++ b/src/app/api/dashboard/summary/route.ts
@@ -44,6 +44,12 @@
  * subsequent iOS polls inside the window hit memory. Invalidation runs
  * via the existing `invalidateUserMeasurements` + the v1.4.38-extended
  * `invalidateUserMedications` hooks.
+ *
+ * Module gate: the emitted `metrics` array is filtered against the account's
+ * module map before it leaves the handler, so a card whose measurement type
+ * belongs to a disabled module never ships. The decision comes from the same
+ * map the shared snapshot builder uses (`disabledSummaryTypes`); the filter
+ * runs OUTSIDE the cache because a module toggle does not evict it.
  */
 import { apiHandler, requireAuth } from "@/lib/api-handler";
 import { apiSuccess } from "@/lib/api-response";
@@ -57,6 +63,8 @@ import { defaultLocale, locales, type Locale } from "@/lib/i18n/config";
 import { userDayKey, DEFAULT_TIMEZONE } from "@/lib/tz/resolver";
 import { cachedSwr, caches, type ServerCache } from "@/lib/cache/server-cache";
 import { buildMedsTodayBlock } from "@/lib/dashboard/meds-today";
+import { resolveModuleMap } from "@/lib/modules/gate";
+import { gateMetricCardsByModules } from "@/lib/dashboard/widget-modules";
 import {
   summarizeSleepNights,
   reconstructSleepNights,
@@ -364,7 +372,35 @@ export const GET = apiHandler(async () => {
     annotate,
   );
 
-  return apiSuccess(body);
+  // ── module gate ───────────────────────────────────────────────────
+  // This route builds its own payload instead of going through
+  // `readDashboardSnapshotCached`, so it never picked up the module gate
+  // the shared snapshot builder applies — it emitted glucose and sleep
+  // tiles on data presence alone, while `/api/dashboard/snapshot` correctly
+  // withheld them for the same account.
+  //
+  // OMIT, NOT 403 — matching the snapshot sibling and the sync feed. This is
+  // an aggregate of ten metric cards across several domains; refusing the
+  // whole request would blank the iOS dashboard because one module is off.
+  // The card simply does not appear, which is exactly what a disabled module
+  // means on every other dashboard surface.
+  //
+  // Applied AFTER the cache read, deliberately. The analytics LRU is keyed
+  // `<userId>|dashboard-summary` with a 60 s fresh / 1 h stale window, and
+  // toggling a module does not evict it — gating inside the builder would
+  // leave the disabled tile served for up to an hour after the user turned
+  // it off. Filtering the cached body makes the toggle effective on the very
+  // next request.
+  const modules = await resolveModuleMap(user.id);
+  const metrics = gateMetricCardsByModules(body.metrics, modules);
+  annotate({
+    meta: {
+      metrics_emitted: metrics.length,
+      metrics_gated: body.metrics.length - metrics.length,
+    },
+  });
+
+  return apiSuccess({ ...body, metrics });
 });
 
 interface SummaryBuilderContext {
diff --git a/src/app/api/fhir/$everything/route.ts b/src/app/api/fhir/$everything/route.ts
index e804b1f0e..e42a49b80 100644
--- a/src/app/api/fhir/$everything/route.ts
+++ b/src/app/api/fhir/$everything/route.ts
@@ -10,6 +10,7 @@
 import { NextRequest } from "next/server";
 
 import { apiHandler, requireAuth } from "@/lib/api-handler";
+import { requireModuleEnabled } from "@/lib/modules/gate";
 import { annotate } from "@/lib/logging/context";
 import { checkRateLimit } from "@/lib/rate-limit";
 import {
@@ -32,6 +33,21 @@ export const GET = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth(FHIR_READ_SCOPE);
   annotate({ action: { name: "fhir.everything.read" } });
 
+  // v1.30 — the FHIR REST face serves the SAME whole-record aggregate as
+  // `/api/export/health-record` (the doctor-report builder), right down to
+  // the decrypted insurance number on the Patient resource. That export
+  // gates on the `doctorReport` module; this surface did not, so the module
+  // could be off and `/api/fhir/*` still handed out the full record.
+  //
+  // REFUSE, NOT OMIT — deliberately, and unlike the sync delta feed. This is
+  // a whole-record export, not an incremental feed: there is no partial
+  // answer that is still a truthful FHIR Bundle, and no background client
+  // depends on it draining to stay consistent. Mirroring the sibling export's
+  // 403 `module.disabled` envelope (rather than an OperationOutcome) keeps
+  // the errorCode the clients already branch on for a disabled module.
+  const gate = await requireModuleEnabled(user.id, "doctorReport");
+  if (!gate.enabled) return gate.response;
+
   const rl = await checkRateLimit(`fhir:${user.id}`, 120, 60 * 60 * 1000);
   if (!rl.allowed) {
     return operationOutcome(429, "throttled", "Rate limit exceeded");
diff --git a/src/app/api/fhir/MedicationAdministration/route.ts b/src/app/api/fhir/MedicationAdministration/route.ts
index a8e489309..747b8f71b 100644
--- a/src/app/api/fhir/MedicationAdministration/route.ts
+++ b/src/app/api/fhir/MedicationAdministration/route.ts
@@ -9,6 +9,7 @@
 import { NextRequest } from "next/server";
 
 import { apiHandler, requireAuth } from "@/lib/api-handler";
+import { requireModuleEnabled } from "@/lib/modules/gate";
 import { annotate } from "@/lib/logging/context";
 import { checkRateLimit } from "@/lib/rate-limit";
 import { medicationAdministrationsFromReportData } from "@/lib/fhir/resources";
@@ -24,6 +25,21 @@ export const GET = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth(FHIR_READ_SCOPE);
   annotate({ action: { name: "fhir.medicationadministration.search" } });
 
+  // v1.30 — the FHIR REST face serves the SAME whole-record aggregate as
+  // `/api/export/health-record` (the doctor-report builder), right down to
+  // the decrypted insurance number on the Patient resource. That export
+  // gates on the `doctorReport` module; this surface did not, so the module
+  // could be off and `/api/fhir/*` still handed out the full record.
+  //
+  // REFUSE, NOT OMIT — deliberately, and unlike the sync delta feed. This is
+  // a whole-record export, not an incremental feed: there is no partial
+  // answer that is still a truthful FHIR Bundle, and no background client
+  // depends on it draining to stay consistent. Mirroring the sibling export's
+  // 403 `module.disabled` envelope (rather than an OperationOutcome) keeps
+  // the errorCode the clients already branch on for a disabled module.
+  const gate = await requireModuleEnabled(user.id, "doctorReport");
+  if (!gate.enabled) return gate.response;
+
   const rl = await checkRateLimit(`fhir:${user.id}`, 120, 60 * 60 * 1000);
   if (!rl.allowed) {
     return operationOutcome(429, "throttled", "Rate limit exceeded");
diff --git a/src/app/api/fhir/MedicationStatement/route.ts b/src/app/api/fhir/MedicationStatement/route.ts
index 6cbafb86b..b7565735d 100644
--- a/src/app/api/fhir/MedicationStatement/route.ts
+++ b/src/app/api/fhir/MedicationStatement/route.ts
@@ -10,6 +10,7 @@
 import { NextRequest } from "next/server";
 
 import { apiHandler, requireAuth } from "@/lib/api-handler";
+import { requireModuleEnabled } from "@/lib/modules/gate";
 import { annotate } from "@/lib/logging/context";
 import { checkRateLimit } from "@/lib/rate-limit";
 import { medicationStatementsFromReportData } from "@/lib/fhir/resources";
@@ -25,6 +26,21 @@ export const GET = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth(FHIR_READ_SCOPE);
   annotate({ action: { name: "fhir.medicationstatement.search" } });
 
+  // v1.30 — the FHIR REST face serves the SAME whole-record aggregate as
+  // `/api/export/health-record` (the doctor-report builder), right down to
+  // the decrypted insurance number on the Patient resource. That export
+  // gates on the `doctorReport` module; this surface did not, so the module
+  // could be off and `/api/fhir/*` still handed out the full record.
+  //
+  // REFUSE, NOT OMIT — deliberately, and unlike the sync delta feed. This is
+  // a whole-record export, not an incremental feed: there is no partial
+  // answer that is still a truthful FHIR Bundle, and no background client
+  // depends on it draining to stay consistent. Mirroring the sibling export's
+  // 403 `module.disabled` envelope (rather than an OperationOutcome) keeps
+  // the errorCode the clients already branch on for a disabled module.
+  const gate = await requireModuleEnabled(user.id, "doctorReport");
+  if (!gate.enabled) return gate.response;
+
   const rl = await checkRateLimit(`fhir:${user.id}`, 120, 60 * 60 * 1000);
   if (!rl.allowed) {
     return operationOutcome(429, "throttled", "Rate limit exceeded");
diff --git a/src/app/api/fhir/Observation/route.ts b/src/app/api/fhir/Observation/route.ts
index c440b2577..22760e71b 100644
--- a/src/app/api/fhir/Observation/route.ts
+++ b/src/app/api/fhir/Observation/route.ts
@@ -10,6 +10,7 @@
 import { NextRequest } from "next/server";
 
 import { apiHandler, requireAuth } from "@/lib/api-handler";
+import { requireModuleEnabled } from "@/lib/modules/gate";
 import { annotate } from "@/lib/logging/context";
 import { checkRateLimit } from "@/lib/rate-limit";
 import { observationsFromReportData } from "@/lib/fhir/resources";
@@ -25,6 +26,21 @@ export const GET = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth(FHIR_READ_SCOPE);
   annotate({ action: { name: "fhir.observation.search" } });
 
+  // v1.30 — the FHIR REST face serves the SAME whole-record aggregate as
+  // `/api/export/health-record` (the doctor-report builder), right down to
+  // the decrypted insurance number on the Patient resource. That export
+  // gates on the `doctorReport` module; this surface did not, so the module
+  // could be off and `/api/fhir/*` still handed out the full record.
+  //
+  // REFUSE, NOT OMIT — deliberately, and unlike the sync delta feed. This is
+  // a whole-record export, not an incremental feed: there is no partial
+  // answer that is still a truthful FHIR Bundle, and no background client
+  // depends on it draining to stay consistent. Mirroring the sibling export's
+  // 403 `module.disabled` envelope (rather than an OperationOutcome) keeps
+  // the errorCode the clients already branch on for a disabled module.
+  const gate = await requireModuleEnabled(user.id, "doctorReport");
+  if (!gate.enabled) return gate.response;
+
   const rl = await checkRateLimit(`fhir:${user.id}`, 120, 60 * 60 * 1000);
   if (!rl.allowed) {
     return operationOutcome(429, "throttled", "Rate limit exceeded");
diff --git a/src/app/api/fhir/Patient/route.ts b/src/app/api/fhir/Patient/route.ts
index 19d6e1aa8..c6e2f3b74 100644
--- a/src/app/api/fhir/Patient/route.ts
+++ b/src/app/api/fhir/Patient/route.ts
@@ -9,6 +9,7 @@
 import { NextRequest } from "next/server";
 
 import { apiHandler, requireAuth } from "@/lib/api-handler";
+import { requireModuleEnabled } from "@/lib/modules/gate";
 import { annotate } from "@/lib/logging/context";
 import { checkRateLimit } from "@/lib/rate-limit";
 import { patientResource } from "@/lib/fhir/resources";
@@ -24,6 +25,21 @@ export const GET = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth(FHIR_READ_SCOPE);
   annotate({ action: { name: "fhir.patient.search" } });
 
+  // v1.30 — the FHIR REST face serves the SAME whole-record aggregate as
+  // `/api/export/health-record` (the doctor-report builder), right down to
+  // the decrypted insurance number on the Patient resource. That export
+  // gates on the `doctorReport` module; this surface did not, so the module
+  // could be off and `/api/fhir/*` still handed out the full record.
+  //
+  // REFUSE, NOT OMIT — deliberately, and unlike the sync delta feed. This is
+  // a whole-record export, not an incremental feed: there is no partial
+  // answer that is still a truthful FHIR Bundle, and no background client
+  // depends on it draining to stay consistent. Mirroring the sibling export's
+  // 403 `module.disabled` envelope (rather than an OperationOutcome) keeps
+  // the errorCode the clients already branch on for a disabled module.
+  const gate = await requireModuleEnabled(user.id, "doctorReport");
+  if (!gate.enabled) return gate.response;
+
   const rl = await checkRateLimit(`fhir:${user.id}`, 120, 60 * 60 * 1000);
   if (!rl.allowed) {
     return operationOutcome(429, "throttled", "Rate limit exceeded");
diff --git a/src/app/api/fhir/__tests__/module-gate.test.ts b/src/app/api/fhir/__tests__/module-gate.test.ts
new file mode 100644
index 000000000..f869a3e75
--- /dev/null
+++ b/src/app/api/fhir/__tests__/module-gate.test.ts
@@ -0,0 +1,179 @@
+/**
+ * `/api/fhir/*` — doctorReport module gate.
+ *
+ * The FHIR REST face serves the same whole-record aggregate as
+ * `/api/export/health-record`, including the decrypted insurance number on
+ * the Patient resource. The export gates on the `doctorReport` module; the
+ * FHIR routes did not, so the module could be off and `$everything` still
+ * returned the full Bundle to the same token.
+ *
+ * REFUSE, not omit — a whole-record export has no truthful partial answer.
+ * Every data route 403s with the shared `module.disabled` envelope; only the
+ * static CapabilityStatement at `/api/fhir/metadata` stays open (server
+ * metadata, no user data).
+ *
+ * Behavioural: the assertions read status codes and check that no aggregate
+ * was ever loaded, so removing a gate turns them red.
+ */
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { NextRequest } from "next/server";
+
+vi.mock("@/lib/auth/session", () => ({ getSession: vi.fn() }));
+vi.mock("@/lib/rate-limit", () => ({ checkRateLimit: vi.fn() }));
+vi.mock("@/lib/logging/transports", () => ({ emitIfSampled: vi.fn() }));
+vi.mock("@/lib/db-compat", () => ({
+  ensureDbCompatibility: vi.fn().mockResolvedValue(undefined),
+}));
+// The module gate itself is NOT mocked — the whole point is to exercise the
+// real resolver and the real 403 envelope. Only its data sources are stubbed,
+// so the module state is driven the same way production drives it: through
+// the persisted `modulePreferencesJson` allowlist.
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    user: { findUnique: vi.fn() },
+    cycleProfile: { findUnique: vi.fn() },
+  },
+}));
+vi.mock("@/lib/modules/operator-availability", async (importOriginal) => {
+  const actual =
+    await importOriginal<
+      typeof import("@/lib/modules/operator-availability")
+    >();
+  return { ...actual, getOperatorModuleAvailability: vi.fn() };
+});
+vi.mock("@/lib/fhir/rest", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("@/lib/fhir/rest")>();
+  return { ...actual, loadFhirContext: vi.fn() };
+});
+vi.mock("@/lib/fhir/resources", () => ({
+  GERMAN_ATC_DEFAULT_LOCALES: ["de"],
+  patientResource: vi.fn(() => ({ resourceType: "Patient", id: "p-1" })),
+  coverageResource: vi.fn(() => null),
+  observationsFromReportData: vi.fn(() => []),
+  medicationStatementsFromReportData: vi.fn(() => []),
+  medicationAdministrationsFromReportData: vi.fn(() => []),
+}));
+vi.mock("next/headers", () => ({
+  headers: vi.fn(async () => ({ get: () => null })),
+  cookies: vi.fn(async () => ({
+    get: () => undefined,
+    set: () => {},
+    delete: () => {},
+  })),
+}));
+
+import { GET as patientGet } from "../Patient/route";
+import { GET as observationGet } from "../Observation/route";
+import { GET as medStatementGet } from "../MedicationStatement/route";
+import { GET as medAdminGet } from "../MedicationAdministration/route";
+import { GET as everythingGet } from "../$everything/route";
+import { GET as metadataGet } from "../metadata/route";
+
+import { getSession } from "@/lib/auth/session";
+import { checkRateLimit } from "@/lib/rate-limit";
+import { MODULE_DISABLED_ERROR_CODE, MODULE_KEYS } from "@/lib/modules/gate";
+import { getOperatorModuleAvailability } from "@/lib/modules/operator-availability";
+import { loadFhirContext } from "@/lib/fhir/rest";
+import { prisma } from "@/lib/db";
+
+/**
+ * Drive the REAL gate the way production does — through the persisted
+ * `modulePreferencesJson` disabled-allowlist, where only a literal `false`
+ * turns a module off.
+ */
+function setDoctorReportModule(enabled: boolean): void {
+  vi.mocked(prisma.user.findUnique).mockResolvedValue({
+    gender: null,
+    disableCoach: false,
+    modulePreferencesJson: enabled ? {} : { doctorReport: false },
+  } as never);
+  vi.mocked(prisma.cycleProfile.findUnique).mockResolvedValue(null as never);
+}
+
+const SESSION_OK = {
+  session: { id: "sess-1", expiresAt: new Date(Date.now() + 3_600_000) },
+  user: { id: "user-1", username: "tester", role: "USER" as const },
+};
+
+/** Every data route under `/api/fhir`, by the path a caller would hit. */
+const DATA_ROUTES: ReadonlyArray<
+  [string, (req: NextRequest) => Promise<Response>]
+> = [
+  ["Patient", patientGet],
+  ["Observation", observationGet],
+  ["MedicationStatement", medStatementGet],
+  ["MedicationAdministration", medAdminGet],
+  ["$everything", everythingGet],
+];
+
+function req(path: string): NextRequest {
+  return new NextRequest(`http://localhost/api/fhir/${path}`);
+}
+
+beforeEach(() => {
+  vi.resetAllMocks();
+  vi.mocked(getSession).mockResolvedValue(SESSION_OK as never);
+  vi.mocked(checkRateLimit).mockResolvedValue({
+    allowed: true,
+    count: 1,
+    resetAt: Date.now(),
+  } as never);
+  // Operator layer available for every module; the per-user layer is what
+  // each test drives.
+  vi.mocked(getOperatorModuleAvailability).mockResolvedValue(
+    Object.fromEntries(MODULE_KEYS.map((k) => [k, true])) as never,
+  );
+  vi.mocked(loadFhirContext).mockResolvedValue({
+    data: {} as never,
+    identity: { insuranceNumber: "A123456789" },
+    germanAtc: false,
+  });
+});
+
+describe("/api/fhir/* — doctorReport module gate", () => {
+  describe.each(DATA_ROUTES)("GET /api/fhir/%s", (path, handler) => {
+    it("403s with module.disabled when the module is off", async () => {
+      setDoctorReportModule(false);
+
+      const res = await handler(req(path));
+      expect(res.status).toBe(403);
+
+      const body = (await res.json()) as {
+        data: unknown;
+        error: string;
+        meta?: { errorCode?: string; module?: string };
+      };
+      expect(body.data).toBeNull();
+      expect(body.meta?.errorCode).toBe(MODULE_DISABLED_ERROR_CODE);
+      expect(body.meta?.module).toBe("doctorReport");
+
+      // Refused before any record was assembled — the insurance number
+      // never left the store.
+      expect(loadFhirContext).not.toHaveBeenCalled();
+      expect(JSON.stringify(body)).not.toContain("A123456789");
+    });
+
+    it("serves the Bundle when the module is on", async () => {
+      setDoctorReportModule(true);
+
+      const res = await handler(req(path));
+      expect(res.status).toBe(200);
+      expect(res.headers.get("content-type")).toContain(
+        "application/fhir+json",
+      );
+
+      const bundle = (await res.json()) as { resourceType: string };
+      expect(bundle.resourceType).toBe("Bundle");
+      expect(loadFhirContext).toHaveBeenCalledWith("user-1");
+    });
+  });
+
+  it("leaves the static CapabilityStatement reachable while the module is off", async () => {
+    // Server metadata, no user data — the one FHIR route that stays open.
+    setDoctorReportModule(false);
+    const res = await metadataGet();
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as { resourceType: string };
+    expect(body.resourceType).toBe("CapabilityStatement");
+  });
+});
diff --git a/src/app/api/fhir/__tests__/route.test.ts b/src/app/api/fhir/__tests__/route.test.ts
index 78b000b4e..0a061e8da 100644
--- a/src/app/api/fhir/__tests__/route.test.ts
+++ b/src/app/api/fhir/__tests__/route.test.ts
@@ -16,6 +16,10 @@ vi.mock("@/lib/logging/transports", () => ({ emitIfSampled: vi.fn() }));
 vi.mock("@/lib/db-compat", () => ({
   ensureDbCompatibility: vi.fn().mockResolvedValue(undefined),
 }));
+vi.mock("@/lib/modules/gate", () => ({
+  requireModuleEnabled: vi.fn(),
+  isModuleEnabled: vi.fn(),
+}));
 vi.mock("@/lib/fhir/rest", async (importOriginal) => {
   const actual = await importOriginal<typeof import("@/lib/fhir/rest")>();
   return { ...actual, loadFhirContext: vi.fn() };
@@ -36,6 +40,7 @@ import { GET as observationGet } from "../Observation/route";
 import { getSession } from "@/lib/auth/session";
 import { checkRateLimit } from "@/lib/rate-limit";
 import { loadFhirContext, MAX_COUNT } from "@/lib/fhir/rest";
+import { requireModuleEnabled, isModuleEnabled } from "@/lib/modules/gate";
 import { observationsFromReportData } from "@/lib/fhir/resources";
 
 const SESSION_OK = {
@@ -65,6 +70,10 @@ beforeEach(() => {
     count: 1,
     resetAt: Date.now(),
   } as never);
+  // The doctorReport module is ON for the contract assertions below; the
+  // OFF behaviour is pinned in `module-gate.test.ts`.
+  vi.mocked(requireModuleEnabled).mockResolvedValue({ enabled: true });
+  vi.mocked(isModuleEnabled).mockResolvedValue(true);
   vi.mocked(loadFhirContext).mockResolvedValue({
     data: {} as never,
     identity: { insuranceNumber: null },
diff --git a/src/app/api/sync/changes/__tests__/module-gate.test.ts b/src/app/api/sync/changes/__tests__/module-gate.test.ts
new file mode 100644
index 000000000..5b5e004c9
--- /dev/null
+++ b/src/app/api/sync/changes/__tests__/module-gate.test.ts
@@ -0,0 +1,198 @@
+/**
+ * `GET /api/sync/changes` — cycle module gate.
+ *
+ * The delta feed multiplexes five domains over one cursor and used to serve
+ * `cycleDays` / `cycles` ungated, so an account with cycle tracking off got
+ * period days and per-day symptom rows over the very token that
+ * `/api/cycle/*` refuses with a 403.
+ *
+ * Behavioural, not structural: the assertions read the response body and the
+ * Prisma call log, so reverting the gate in the route turns them red.
+ */
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { NextRequest } from "next/server";
+
+vi.mock("@/lib/auth/session", () => ({ getSession: vi.fn() }));
+vi.mock("@/lib/rate-limit", () => ({ checkRateLimit: vi.fn() }));
+vi.mock("@/lib/logging/transports", () => ({ emitIfSampled: vi.fn() }));
+vi.mock("@/lib/db-compat", () => ({
+  ensureDbCompatibility: vi.fn().mockResolvedValue(undefined),
+}));
+vi.mock("@/lib/modules/gate", () => ({ isModuleEnabled: vi.fn() }));
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    measurement: { findMany: vi.fn() },
+    moodEntry: { findMany: vi.fn() },
+    medicationIntakeEvent: { findMany: vi.fn() },
+    cycleDayLog: { findMany: vi.fn() },
+    menstrualCycle: { findMany: vi.fn() },
+  },
+}));
+vi.mock("next/headers", () => ({
+  headers: vi.fn(async () => ({ get: () => null })),
+  cookies: vi.fn(async () => ({
+    get: () => undefined,
+    set: () => {},
+    delete: () => {},
+  })),
+}));
+
+import { GET } from "../route";
+import { getSession } from "@/lib/auth/session";
+import { checkRateLimit } from "@/lib/rate-limit";
+import { isModuleEnabled } from "@/lib/modules/gate";
+import { prisma } from "@/lib/db";
+import { decodeCursor } from "@/lib/sync/cursor";
+
+const SESSION_OK = {
+  session: { id: "sess-1", expiresAt: new Date(Date.now() + 3_600_000) },
+  user: { id: "user-1", username: "tester", role: "USER" as const },
+};
+
+const NOW = new Date("2026-07-01T12:00:00.000Z");
+
+/** One live cycle-day row carrying a symptom — the payload that must not leak. */
+const CYCLE_DAY_ROW = {
+  id: "cd-1",
+  userId: "user-1",
+  externalId: "ext-cd-1",
+  date: NOW,
+  flow: "MEDIUM",
+  notes: null,
+  notesEncrypted: null,
+  syncVersion: 3,
+  deletedAt: null,
+  updatedAt: NOW,
+  createdAt: NOW,
+  symptoms: [{ id: "sym-1", symptom: "CRAMPS", severity: 2 }],
+};
+
+const CYCLE_ROW = {
+  id: "mc-1",
+  userId: "user-1",
+  startDate: NOW,
+  endDate: null,
+  cycleLength: 28,
+  periodLength: 5,
+  predicted: false,
+  syncVersion: 2,
+  deletedAt: null,
+  updatedAt: NOW,
+  createdAt: NOW,
+};
+
+interface FeedBody {
+  data: {
+    changes: {
+      measurements: { upserts: unknown[]; tombstones: unknown[] };
+      cycleDays: { upserts: unknown[]; tombstones: unknown[] };
+      cycles: { upserts: unknown[]; tombstones: unknown[] };
+    };
+    cursor: string | null;
+  };
+}
+
+function req(query = ""): NextRequest {
+  return new NextRequest(`http://localhost/api/sync/changes${query}`);
+}
+
+beforeEach(() => {
+  vi.resetAllMocks();
+  vi.mocked(getSession).mockResolvedValue(SESSION_OK as never);
+  vi.mocked(checkRateLimit).mockResolvedValue({
+    allowed: true,
+    count: 1,
+    resetAt: Date.now(),
+  } as never);
+  // Non-cycle domains always return rows so a 403/empty-everything result
+  // cannot be mistaken for a passing "cycle omitted" assertion.
+  vi.mocked(prisma.measurement.findMany).mockResolvedValue([
+    {
+      id: "m-1",
+      externalId: "ext-m-1",
+      type: "WEIGHT",
+      value: 80,
+      unit: "kg",
+      measuredAt: NOW,
+      source: "MANUAL",
+      notes: null,
+      notesEncrypted: null,
+      syncVersion: 1,
+      deletedAt: null,
+      updatedAt: NOW,
+    },
+  ] as never);
+  vi.mocked(prisma.moodEntry.findMany).mockResolvedValue([] as never);
+  vi.mocked(prisma.medicationIntakeEvent.findMany).mockResolvedValue(
+    [] as never,
+  );
+  vi.mocked(prisma.cycleDayLog.findMany).mockResolvedValue([
+    CYCLE_DAY_ROW,
+  ] as never);
+  vi.mocked(prisma.menstrualCycle.findMany).mockResolvedValue([
+    CYCLE_ROW,
+  ] as never);
+});
+
+describe("GET /api/sync/changes — cycle module gate", () => {
+  it("omits cycle rows and never queries them when the module is off", async () => {
+    vi.mocked(isModuleEnabled).mockResolvedValue(false);
+
+    const res = await GET(req());
+    // OMIT, not refuse — the other four domains must keep syncing.
+    expect(res.status).toBe(200);
+
+    const body = (await res.json()) as FeedBody;
+    expect(body.data.changes.cycleDays.upserts).toEqual([]);
+    expect(body.data.changes.cycleDays.tombstones).toEqual([]);
+    expect(body.data.changes.cycles.upserts).toEqual([]);
+    expect(body.data.changes.cycles.tombstones).toEqual([]);
+
+    // The rest of the feed is untouched — proves the empty cycle blocks are
+    // the gate, not a wholesale refusal.
+    expect(body.data.changes.measurements.upserts).toHaveLength(1);
+
+    // Not read out of Postgres at all.
+    expect(prisma.cycleDayLog.findMany).not.toHaveBeenCalled();
+    expect(prisma.menstrualCycle.findMany).not.toHaveBeenCalled();
+
+    // No symptom string anywhere in the serialised payload.
+    expect(JSON.stringify(body)).not.toContain("CRAMPS");
+    expect(JSON.stringify(body)).not.toContain("ext-cd-1");
+  });
+
+  it("serves cycle rows when the module is on", async () => {
+    vi.mocked(isModuleEnabled).mockResolvedValue(true);
+
+    const res = await GET(req());
+    expect(res.status).toBe(200);
+
+    const body = (await res.json()) as FeedBody;
+    expect(body.data.changes.cycleDays.upserts).toHaveLength(1);
+    expect(body.data.changes.cycles.upserts).toHaveLength(1);
+    expect(prisma.cycleDayLog.findMany).toHaveBeenCalledTimes(1);
+    expect(prisma.menstrualCycle.findMany).toHaveBeenCalledTimes(1);
+  });
+
+  it("gates on the cycle module key specifically", async () => {
+    vi.mocked(isModuleEnabled).mockResolvedValue(true);
+    await GET(req());
+    expect(isModuleEnabled).toHaveBeenCalledWith("user-1", "cycle");
+  });
+
+  it("leaves the cycle cursor watermarks untouched while the module is off", async () => {
+    // A skipped domain must not advance its watermark, so re-enabling
+    // resumes from where the client left off rather than skipping the rows
+    // that changed while the module was hidden.
+    vi.mocked(isModuleEnabled).mockResolvedValue(false);
+    const res = await GET(req());
+    const body = (await res.json()) as FeedBody;
+
+    const cursor = decodeCursor(body.data.cursor as string);
+    expect(cursor).not.toBeNull();
+    expect(cursor!.cycleDays).toBeUndefined();
+    expect(cursor!.cycles).toBeUndefined();
+    // The domain that did return rows advanced normally.
+    expect(cursor!.measurements).toBeDefined();
+  });
+});
diff --git a/src/app/api/sync/changes/route.ts b/src/app/api/sync/changes/route.ts
index b790d4350..750ea47f5 100644
--- a/src/app/api/sync/changes/route.ts
+++ b/src/app/api/sync/changes/route.ts
@@ -37,6 +37,9 @@
  *     been pruned, so an incremental delta could silently miss it).
  *   - `syncVersion` is echoed per row so the client can keep its mirror's
  *     version monotonic.
+ *   - The `cycleDays` / `cycles` blocks are MODULE-GATED: an account with
+ *     cycle tracking off gets both blocks empty (never a 403 — see the
+ *     gate note in the handler) and their cursor watermarks untouched.
  *
  * `apiHandler` + `requireAuth` (cookie OR Bearer; iOS uses Bearer).
  * Read-only — no idempotency, no write side-effect (unlike the legacy
@@ -67,6 +70,7 @@ import {
   type CycleDayLogDTO,
   type MenstrualCycleDTO,
 } from "@/lib/cycle/dto";
+import { isModuleEnabled } from "@/lib/modules/gate";
 
 const DEFAULT_LIMIT = 200;
 const MAX_LIMIT = 500;
@@ -192,6 +196,36 @@ export const GET = apiHandler(async (request: NextRequest) => {
 
   const serverNow = new Date();
 
+  // ── module gate: cycle ────────────────────────────────────────────
+  // The `cycleDays` / `cycles` domains carry period days and per-day
+  // symptom rows — the same data every `/api/cycle/*` route refuses with a
+  // 403 when the module is off. Without this the delta feed re-served them
+  // ungated to the very same token.
+  //
+  // OMIT, NOT 403 — deliberately, and unlike the whole-record FHIR export.
+  // This feed multiplexes five domains over one cursor: refusing the whole
+  // request would wedge measurement / mood / intake catch-up for every
+  // account with cycle tracking off, which (the gate delegates to
+  // `isCycleEnabled`) is the default for most accounts. A partial payload
+  // is the only outcome that keeps the client syncing while still honouring
+  // the promise that a disabled module hands out nothing.
+  //
+  // The two cycle watermarks are deliberately NOT advanced while the module
+  // is off (the queries are skipped, so `advanceCursor` sees an empty page
+  // and leaves the prior watermark untouched). Re-enabling therefore resumes
+  // from where the client actually left off instead of silently skipping the
+  // rows that changed while the module was hidden.
+  //
+  // KNOWN GAP, out of scope here: a client that synced cycle rows BEFORE the
+  // module was turned off keeps its stale local mirror. Emitting tombstones
+  // for them would be wrong — a tombstone means deleted, and disabling a
+  // module must leave the rows intact so re-enabling finds a complete
+  // history. Purging a paired client's mirror needs an explicit
+  // "module went dark" signal in the feed contract plus client support for
+  // it; that is an additive wire change and an iOS-client change, not a
+  // server-side gate fix, so it is left for a coordinated contract cycle.
+  const cycleEnabled = await isModuleEnabled(user.id, "cycle");
+
   // The retention horizon: tombstones older than this may have been
   // pruned by the cleanup job, so a cursor that predates it can no longer
   // be trusted to deliver every deletion incrementally.
@@ -291,17 +325,23 @@ export const GET = apiHandler(async (request: NextRequest) => {
           updatedAt: true,
         },
       }),
-      prisma.cycleDayLog.findMany({
-        where: { userId: user.id, ...keysetFilter(cursor.cycleDays) },
-        orderBy: [{ updatedAt: "asc" }, { id: "asc" }],
-        take: limit + 1,
-        include: dayLogSymptomInclude,
-      }),
-      prisma.menstrualCycle.findMany({
-        where: { userId: user.id, ...keysetFilter(cursor.cycles) },
-        orderBy: [{ updatedAt: "asc" }, { id: "asc" }],
-        take: limit + 1,
-      }),
+      // Skipped outright when the module is off — not filtered after the
+      // fact — so the disabled rows are never read out of Postgres at all.
+      cycleEnabled
+        ? prisma.cycleDayLog.findMany({
+            where: { userId: user.id, ...keysetFilter(cursor.cycleDays) },
+            orderBy: [{ updatedAt: "asc" }, { id: "asc" }],
+            take: limit + 1,
+            include: dayLogSymptomInclude,
+          })
+        : [],
+      cycleEnabled
+        ? prisma.menstrualCycle.findMany({
+            where: { userId: user.id, ...keysetFilter(cursor.cycles) },
+            orderBy: [{ updatedAt: "asc" }, { id: "asc" }],
+            take: limit + 1,
+          })
+        : [],
     ]);
 
   const nextCursor: SyncCursor = { ...cursor };
@@ -464,6 +504,7 @@ export const GET = apiHandler(async (request: NextRequest) => {
       cycle_day_tombstones: cycleDayTombstones.length,
       cycle_upserts: cycleUpserts.length,
       cycle_tombstones: cycleTombstones.length,
+      cycle_module_enabled: cycleEnabled,
       has_more: hasMore,
       cursor_present: Boolean(parsed.data.cursor),
     },
diff --git a/src/lib/dashboard/snapshot.ts b/src/lib/dashboard/snapshot.ts
index 5ce296350..82b63d4c2 100644
--- a/src/lib/dashboard/snapshot.ts
+++ b/src/lib/dashboard/snapshot.ts
@@ -118,7 +118,7 @@ export {
 } from "@/lib/dashboard/widget-modules";
 import {
   WIDGET_MODULE_BY_ID,
-  SUMMARY_TYPE_MODULE,
+  disabledSummaryTypes,
 } from "@/lib/dashboard/widget-modules";
 
 const GLUCOSE_CONTEXTS = [
@@ -965,10 +965,9 @@ function gateSummariesByModules(
   summaries: Record<string, DataSummary>;
   lastSeenByType: Record<string, { lastSeenAt: string } | null>;
 } {
-  const dropped = new Set<string>();
-  for (const [type, moduleKey] of Object.entries(SUMMARY_TYPE_MODULE)) {
-    if (moduleKey && modules[moduleKey] === false) dropped.add(type);
-  }
+  // The drop decision is shared with `GET /api/dashboard/summary` — see
+  // `disabledSummaryTypes`. Only the filtering below is snapshot-shaped.
+  const dropped = disabledSummaryTypes(modules);
   if (dropped.size === 0) return { summaries, lastSeenByType };
   const outSummaries: Record<string, DataSummary> = {};
   for (const [type, summary] of Object.entries(summaries)) {
diff --git a/src/lib/dashboard/widget-modules.ts b/src/lib/dashboard/widget-modules.ts
index b03ddd973..ee12a8dfa 100644
--- a/src/lib/dashboard/widget-modules.ts
+++ b/src/lib/dashboard/widget-modules.ts
@@ -75,3 +75,70 @@ export const SUMMARY_TYPE_MODULE: Partial<Record<string, ModuleKey>> = {
   // on the `nutrients` module like the rest of that store's surfaces.
   NUTRIENT_WATER: "nutrients",
 };
+
+/**
+ * The summary types a module map turns off. Lifted out of
+ * `gateSummariesByModules` in `@/lib/dashboard/snapshot` so the two
+ * dashboard aggregates that both surface per-metric data — the snapshot
+ * builder and the iOS `GET /api/dashboard/summary` payload — decide from
+ * ONE map instead of each carrying its own copy.
+ *
+ * The two callers shape their payloads differently (the snapshot keys
+ * summaries by `MeasurementType`; the summary route emits an array of
+ * metric cards keyed by an iOS `MetricKind`), so what is shared is this
+ * decision, not the filtering itself.
+ */
+export function disabledSummaryTypes(
+  modules: Partial<Record<ModuleKey, boolean>>,
+): Set<string> {
+  const dropped = new Set<string>();
+  for (const [type, moduleKey] of Object.entries(SUMMARY_TYPE_MODULE)) {
+    if (moduleKey && modules[moduleKey] === false) dropped.add(type);
+  }
+  return dropped;
+}
+
+/**
+ * iOS `MetricKind` (the `kind` on a `GET /api/dashboard/summary` metric
+ * card) → the `MeasurementType` it is built from. The summary route emits
+ * cards by kind, but module membership is defined per measurement type in
+ * `SUMMARY_TYPE_MODULE` above; this map is the join between the two so the
+ * summary payload gates off the SAME source of truth as the snapshot rather
+ * than a second, drift-prone kind→module list.
+ *
+ * Kinds whose type carries no `SUMMARY_TYPE_MODULE` entry (weight, blood
+ * pressure, pulse, body fat, steps, body water, bone mass, SpO₂) are core
+ * vitals and always pass through — they are listed anyway so a reader can
+ * see the full emitted set and so a new card cannot be added without
+ * deciding which type backs it.
+ */
+export const SUMMARY_METRIC_TYPE_BY_KIND: Record<string, string> = {
+  weight: "WEIGHT",
+  bloodPressure: "BLOOD_PRESSURE_SYS",
+  pulse: "PULSE",
+  bodyFat: "BODY_FAT",
+  glucose: "BLOOD_GLUCOSE",
+  sleep: "SLEEP_DURATION",
+  steps: "ACTIVITY_STEPS",
+  totalBodyWater: "TOTAL_BODY_WATER",
+  boneMass: "BONE_MASS",
+  oxygenSaturation: "OXYGEN_SATURATION",
+};
+
+/**
+ * Drop the metric cards whose backing measurement type belongs to a module
+ * the account turned off. A card whose kind is absent from
+ * `SUMMARY_METRIC_TYPE_BY_KIND` is kept — an unmapped kind is a core metric
+ * or a new one, and silently hiding it would be worse than surfacing it.
+ */
+export function gateMetricCardsByModules<T extends { kind: string }>(
+  cards: ReadonlyArray<T>,
+  modules: Partial<Record<ModuleKey, boolean>>,
+): T[] {
+  const dropped = disabledSummaryTypes(modules);
+  if (dropped.size === 0) return [...cards];
+  return cards.filter((card) => {
+    const type = SUMMARY_METRIC_TYPE_BY_KIND[card.kind];
+    return !type || !dropped.has(type);
+  });
+}
diff --git a/src/lib/fhir/__tests__/rest-module-backstop.test.ts b/src/lib/fhir/__tests__/rest-module-backstop.test.ts
new file mode 100644
index 000000000..e048ee6c5
--- /dev/null
+++ b/src/lib/fhir/__tests__/rest-module-backstop.test.ts
@@ -0,0 +1,83 @@
+/**
+ * `loadFhirContext` — doctorReport module backstop.
+ *
+ * The loader is the one door to the whole-record aggregate the FHIR face
+ * serves, including the decrypted insurance number. Every `/api/fhir/*` data
+ * route carries its own `requireModuleEnabled` gate (that is what produces the
+ * clean 403); this test pins the SECOND layer — the loader refuses outright
+ * rather than trusting that every present and future caller remembered.
+ *
+ * The gate resolver is exercised for real; only its data sources are stubbed.
+ */
+import { describe, it, expect, vi, beforeEach } from "vitest";
+
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    user: { findUnique: vi.fn() },
+    cycleProfile: { findUnique: vi.fn() },
+  },
+}));
+vi.mock("@/lib/modules/operator-availability", async (importOriginal) => {
+  const actual =
+    await importOriginal<
+      typeof import("@/lib/modules/operator-availability")
+    >();
+  return { ...actual, getOperatorModuleAvailability: vi.fn() };
+});
+vi.mock("@/lib/doctor-report-data", () => ({
+  collectDoctorReportData: vi.fn(),
+  normaliseDateRange: vi.fn(() => ({ from: new Date(0), to: new Date() })),
+}));
+vi.mock("@/lib/crypto", () => ({ decrypt: vi.fn(() => "A123456789") }));
+
+import { loadFhirContext } from "@/lib/fhir/rest";
+import { MODULE_KEYS } from "@/lib/modules/gate";
+import { getOperatorModuleAvailability } from "@/lib/modules/operator-availability";
+import { collectDoctorReportData } from "@/lib/doctor-report-data";
+import { prisma } from "@/lib/db";
+
+function setDoctorReportModule(enabled: boolean): void {
+  vi.mocked(prisma.user.findUnique).mockImplementation((async (args: {
+    select?: Record<string, boolean>;
+  }) => {
+    // The gate's own read and the loader's identity read hit the same model.
+    if (args?.select?.modulePreferencesJson) {
+      return {
+        gender: null,
+        disableCoach: false,
+        modulePreferencesJson: enabled ? {} : { doctorReport: false },
+      };
+    }
+    return { insuranceNumberEncrypted: "cipher", locale: "de" };
+  }) as never);
+  vi.mocked(prisma.cycleProfile.findUnique).mockResolvedValue(null as never);
+}
+
+beforeEach(() => {
+  vi.resetAllMocks();
+  vi.mocked(getOperatorModuleAvailability).mockResolvedValue(
+    Object.fromEntries(MODULE_KEYS.map((k) => [k, true])) as never,
+  );
+  vi.mocked(collectDoctorReportData).mockResolvedValue({} as never);
+});
+
+describe("loadFhirContext — doctorReport backstop", () => {
+  it("refuses to assemble the record when the module is off", async () => {
+    setDoctorReportModule(false);
+
+    await expect(loadFhirContext("user-1")).rejects.toThrow(
+      /doctorReport.*disabled/,
+    );
+
+    // Nothing was aggregated and nothing was decrypted.
+    expect(collectDoctorReportData).not.toHaveBeenCalled();
+  });
+
+  it("assembles the record when the module is on", async () => {
+    setDoctorReportModule(true);
+
+    const ctx = await loadFhirContext("user-1");
+    expect(collectDoctorReportData).toHaveBeenCalledTimes(1);
+    expect(ctx.identity.insuranceNumber).toBe("A123456789");
+  });
+});
diff --git a/src/lib/fhir/rest.ts b/src/lib/fhir/rest.ts
index a72d345a3..9094504ed 100644
--- a/src/lib/fhir/rest.ts
+++ b/src/lib/fhir/rest.ts
@@ -22,6 +22,7 @@ import {
   type DoctorReportData,
 } from "@/lib/doctor-report-data";
 import { GERMAN_ATC_DEFAULT_LOCALES } from "@/lib/fhir/resources";
+import { isModuleEnabled } from "@/lib/modules/gate";
 import type {
   FhirBundleEntry,
   FhirBundleLink,
@@ -182,12 +183,28 @@ export function operationOutcome(
  * The window matches the document export's default (`normaliseDateRange`
  * with no override). KVNR decryption is fail-soft: a key-rotation gap on a
  * single row omits the identifier rather than 500-ing the read.
+ *
+ * MODULE BACKSTOP. Every `/api/fhir/*` data route calls
+ * `requireModuleEnabled(userId, "doctorReport")` itself, which is what
+ * produces the clean 403 envelope. This assertion is the second layer: the
+ * loader is the one door to the whole-record aggregate (including the
+ * decrypted insurance number), so it refuses outright rather than trusting
+ * that every present and future caller remembered the gate. It throws
+ * instead of returning an envelope because reaching it means a caller is
+ * missing its gate — a bug to surface, not a flow to serve.
  */
 export async function loadFhirContext(userId: string): Promise<{
   data: DoctorReportData;
   identity: { insuranceNumber: string | null };
   germanAtc: boolean;
 }> {
+  if (!(await isModuleEnabled(userId, "doctorReport"))) {
+    throw new Error(
+      'loadFhirContext called with the "doctorReport" module disabled — ' +
+        "the calling route is missing its requireModuleEnabled gate",
+    );
+  }
+
   const range = normaliseDateRange(undefined);
   const [data, userRow] = await Promise.all([
     collectDoctorReportData(userId, range, {}),