From 8736f44442c1d9151281645881c46bd232d5906c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Bombeck?= <mbombeck@gmail.com>
Date: Thu, 23 Jul 2026 09:15:54 +0200
Subject: [PATCH 1/5] fix(dashboard): stop the score-ring PUT from resending a
 stale layout

The Settings page's instant score-ring toggle PUT the full dashboard
layout, built from the client's cached `remote` snapshot. That snapshot
can go stale mid-flight: if a normal tile/chart Save committed a newer
layout first, the ring request's explicit stale `widgets` (and
`comparisonBaseline` / `chartOverlayPrefs`) still won on write and
silently reverted the just-saved layout whenever it resolved last.

The ring mutation now PUTs only the two ring fields
(`buildRingMutationPayload`). `widgets` joins the existing
preserve-when-absent merge (`LAYOUT_FIELD_MERGE_DISPOSITION`) so an
omitted field is carried forward from whatever is currently stored
instead of a client-held copy, closing the race regardless of request
order.
---
 .../dashboard/widgets/__tests__/route.test.ts | 105 ++++++++++++++++++
 src/app/api/dashboard/widgets/route.ts        |  16 ++-
 .../dashboard-layout-section.test.tsx         |  20 +++-
 .../settings/dashboard-layout-section.tsx     |  34 ++++--
 src/lib/__tests__/dashboard-layout.test.ts    |  61 +++++++++-
 src/lib/dashboard-layout.ts                   |  50 ++++++++-
 6 files changed, 262 insertions(+), 24 deletions(-)

diff --git a/src/app/api/dashboard/widgets/__tests__/route.test.ts b/src/app/api/dashboard/widgets/__tests__/route.test.ts
index 5611f3fc3..258346380 100644
--- a/src/app/api/dashboard/widgets/__tests__/route.test.ts
+++ b/src/app/api/dashboard/widgets/__tests__/route.test.ts
@@ -62,7 +62,13 @@ import {
   DASHBOARD_WIDGET_IDS,
   DASHBOARD_IOS_ONLY_WIDGET_IDS,
   DASHBOARD_WIDGET_CATALOGUE_IDS,
+  DEFAULT_DASHBOARD_LAYOUT,
   serializeDashboardLayout,
+  // v1.32.1 — the exact payload builder `ringMutation.mutationFn` calls
+  // (see the settings component). Importing the shipped function rather
+  // than re-implementing its shape means this test exercises the REAL
+  // client contract against the REAL route, not a hand-rolled stand-in.
+  buildRingMutationPayload,
   type DashboardLayout,
 } from "@/lib/dashboard-layout";
 
@@ -636,3 +642,102 @@ describe("dashboard widgets — preserve-when-absent on PUT", () => {
     }
   });
 });
+
+/**
+ * v1.32.1 — regression for issue #581: dashboard layout changes silently
+ * overwritten by a concurrent score-ring save.
+ *
+ * The scenario from the report: the user edits tile/chart visibility
+ * (local draft B), then reorders/toggles a hero score ring before hitting
+ * Save. The ring PUT (`ringMutation`) fires immediately, built from
+ * whatever layout the client had cached (layout A — the state BEFORE the
+ * draft edit). The normal Save button then PUTs the full draft (layout B)
+ * and commits first. If the earlier-fired ring request resolves AFTER
+ * Save, its body — built from the stale A snapshot — used to carry
+ * `widgets: A` explicitly, and an explicitly-present field always wins on
+ * write. Save's B silently reverted to A even though the ring PUT reported
+ * 200 and only meant to touch the ring selection.
+ *
+ * The fix is `buildRingMutationPayload` (imported from the real component
+ * module, not re-implemented here): it never includes `widgets` at all.
+ * This test proves the SERVER half of the fix — a PUT shaped exactly like
+ * the shipped ring mutation's body preserves whatever layout is CURRENTLY
+ * stored, so the request that resolves last can no longer matter.
+ */
+describe("dashboard widgets — ring-only PUT cannot race a concurrent full-layout Save (regression #581)", () => {
+  it("preserves the widgets a concurrent Save already committed, even though the ring request started from a stale snapshot", async () => {
+    // The state AFTER the normal Save committed layout B — a tile turned
+    // off that was on in the stale snapshot A the ring mutation started
+    // from. Starts from the FULL default widget catalogue (rather than a
+    // single-widget array) so `resolveDashboardLayout`'s auto-upgrade
+    // append (missing catalogue ids get seeded invisible) is a no-op here
+    // and the persisted array can be compared for exact equality below.
+    const savedLayoutB: DashboardLayout = serializeDashboardLayout({
+      version: 1,
+      widgets: DEFAULT_DASHBOARD_LAYOUT.widgets.map((w) =>
+        w.id === "weight" ? { ...w, visible: false, tileVisible: false } : w,
+      ),
+      comparisonBaseline: "lastYear",
+      selectedScoreRings: ["MED_COMPLIANCE"],
+      heroRingOrder: ["HEALTH_SCORE", "MED_COMPLIANCE"],
+    });
+    vi.mocked(prisma.user.findUnique).mockResolvedValue({
+      dashboardWidgetsJson: savedLayoutB,
+    } as never);
+    vi.mocked(prisma.user.update).mockResolvedValue({} as never);
+
+    // The ring mutation's real, shipped payload — built without any
+    // knowledge of layout B. If this were still `{...staleA, ...}` the
+    // stale `widgets`/`comparisonBaseline` would land here explicitly and
+    // overwrite B; `buildRingMutationPayload` never carries them.
+    const ringOnlyBody = buildRingMutationPayload({
+      selectedScoreRings: ["READINESS"],
+      heroRingOrder: ["HEALTH_SCORE", "READINESS"],
+    });
+
+    const res = await callPut(makeReq(ringOnlyBody));
+    expect(res.status).toBe(200);
+
+    const updateArg = vi.mocked(prisma.user.update).mock
+      .calls[0]?.[0] as unknown as {
+      data: { dashboardWidgetsJson: DashboardLayout };
+    };
+    // B's widgets (and comparisonBaseline) survive — the ring PUT never
+    // touched them, so nothing it carries can outrace the Save that
+    // already committed.
+    expect(updateArg.data.dashboardWidgetsJson.widgets).toEqual(
+      savedLayoutB.widgets,
+    );
+    expect(updateArg.data.dashboardWidgetsJson.comparisonBaseline).toBe(
+      "lastYear",
+    );
+    // The ring selection itself DID apply.
+    expect(updateArg.data.dashboardWidgetsJson.selectedScoreRings).toEqual([
+      "READINESS",
+    ]);
+
+    const body = (await res.json()) as { data: DashboardLayout };
+    expect(body.data.widgets[0].visible).toBe(false);
+    expect(body.data.widgets[0].tileVisible).toBe(false);
+    expect(body.data.selectedScoreRings).toEqual(["READINESS"]);
+  });
+
+  it("still accepts a normal full-layout Save (widgets present + replace semantics unchanged)", async () => {
+    vi.mocked(prisma.user.findUnique).mockResolvedValue({
+      dashboardWidgetsJson: null,
+    } as never);
+    vi.mocked(prisma.user.update).mockResolvedValue({} as never);
+
+    const res = await callPut(
+      makeReq({
+        version: 1,
+        widgets: [
+          { id: "weight", visible: false, tileVisible: false, order: 0 },
+        ],
+      }),
+    );
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as { data: DashboardLayout };
+    expect(body.data.widgets[0].visible).toBe(false);
+  });
+});
diff --git a/src/app/api/dashboard/widgets/route.ts b/src/app/api/dashboard/widgets/route.ts
index 790501f5e..d7c8c97f6 100644
--- a/src/app/api/dashboard/widgets/route.ts
+++ b/src/app/api/dashboard/widgets/route.ts
@@ -84,7 +84,15 @@ const layoutSchema = z.object({
     // catalogue (42 ids). The cap only has to clear the catalogue size —
     // the enum bounds each entry and the id set is closed — so it carries
     // headroom rather than tracking the count exactly.
-    .max(50),
+    .max(50)
+    // v1.32.1 — optional + preserve-when-absent (issue #581). The
+    // Settings page's instant score-ring toggle now PUTs ONLY the ring
+    // fields; omitting `widgets` lets the server carry forward whatever
+    // is CURRENTLY stored instead of the ring mutation resending a
+    // client-held snapshot that can go stale mid-flight and race a
+    // concurrent full-layout Save. A normal Save still always sends
+    // `widgets` — this only widens what a PARTIAL PUT can leave out.
+    .optional(),
   // v1.4.16 phase B8 — comparison baseline (Vormonat / Vorjahr) rides
   // on the layout blob per research §7 Q3 (no Prisma migration). Optional
   // so v1.4.15 clients that don't know the field can still PUT.
@@ -285,7 +293,11 @@ export const PUT = apiHandler(async (request: NextRequest) => {
   // visibility / order, while chart prefs are PUT through their own route
   // (`/api/dashboard/chart-overlay-prefs`), the hero rings come from
   // Settings, and `comparisonBaseline` is web-only — an omission from any
-  // one surface must not reset a choice made on another.
+  // one surface must not reset a choice made on another. `widgets` itself
+  // joined this set in v1.32.1 (issue #581): the Settings page's instant
+  // score-ring PUT omits it entirely so it always carries forward
+  // whatever is CURRENTLY stored, rather than a client-held snapshot that
+  // could be stale relative to a concurrent full-layout Save.
   //
   // The preserve set is not a list maintained here: it is derived from
   // `LAYOUT_FIELD_MERGE_DISPOSITION`, which the type system forces to cover
diff --git a/src/components/settings/__tests__/dashboard-layout-section.test.tsx b/src/components/settings/__tests__/dashboard-layout-section.test.tsx
index 1be642928..33eaa1ea4 100644
--- a/src/components/settings/__tests__/dashboard-layout-section.test.tsx
+++ b/src/components/settings/__tests__/dashboard-layout-section.test.tsx
@@ -69,10 +69,7 @@ vi.mock("@/hooks/use-auth", () => ({
 }));
 
 import { I18nProvider } from "@/lib/i18n/context";
-import {
-  DashboardLayoutSection,
-  reorderWidgets,
-} from "../dashboard-layout-section";
+import { DashboardLayoutSection, reorderWidgets } from "../dashboard-layout-section";
 
 function render(node: React.ReactElement, locale: "en" | "de" = "en") {
   return renderToStaticMarkup(
@@ -531,4 +528,19 @@ describe("<DashboardLayoutSection> — health-score anchor + reorder (v1.27.27)"
     // The order is the single source of truth: selection is derived from it.
     expect(src).toMatch(/id !== HEALTH_SCORE_RING_ID/);
   });
+
+  it("the ring mutation builds its body via buildRingMutationPayload, not a `...remote` spread (regression #581 source pin)", () => {
+    const src = readFileSync(
+      join(
+        process.cwd(),
+        "src/components/settings/dashboard-layout-section.tsx",
+      ),
+      "utf8",
+    );
+    expect(src).toContain("buildRingMutationPayload(next)");
+    // The pre-fix shape must never come back: spreading a query-cache
+    // snapshot into the ring PUT body is exactly the stale-`widgets`
+    // race issue #581 reported.
+    expect(src).not.toMatch(/\.\.\.remote,/);
+  });
 });
diff --git a/src/components/settings/dashboard-layout-section.tsx b/src/components/settings/dashboard-layout-section.tsx
index 20a4bb507..ddaf3bd5e 100644
--- a/src/components/settings/dashboard-layout-section.tsx
+++ b/src/components/settings/dashboard-layout-section.tsx
@@ -47,6 +47,7 @@ import {
   MAX_SELECTED_SCORE_RINGS,
   HEALTH_SCORE_RING_ID,
   resolveHeroRingOrder,
+  buildRingMutationPayload,
 } from "@/lib/dashboard-layout";
 import {
   Select,
@@ -327,23 +328,34 @@ export function DashboardLayoutSection({ id }: { id: string }) {
    * machine the rest of the section keeps. The first cut routed ring
    * toggles through the draft, and the combination of an unflushed
    * draft, the server snapshot cache, and client staleness read as
-   * "flipping does nothing, rings appear later". The mutation PUTs the
-   * SERVER layout copy with only `selectedScoreRings` changed (an open
-   * draft's other edits stay unsent and untouched), optimistically
-   * updates the widgets query, and invalidates the dashboard snapshot on
-   * settle so the hero reflects the choice on the next visit.
+   * "flipping does nothing, rings appear later". The mutation
+   * optimistically updates the widgets query and invalidates the
+   * dashboard snapshot on settle so the hero reflects the choice on the
+   * next visit.
+   *
+   * v1.32.1 — the PUT body used to be the FULL server layout copy,
+   * spreading this component's `remote` query-cache snapshot in ahead of
+   * the two ring fields. That snapshot can be stale by the time the
+   * request actually lands: if the normal
+   * tile/chart Save button committed a newer layout first, this
+   * request's explicit — present, not omitted — stale `widgets` (and
+   * `comparisonBaseline` / `chartOverlayPrefs`) still won on write and
+   * silently reverted the just-saved layout (issue #581). The payload
+   * now carries ONLY the ring fields; the server's preserve-when-absent
+   * merge (`LAYOUT_FIELD_MERGE_DISPOSITION` — `widgets` joined it in the
+   * same release) carries every omitted field forward from whatever is
+   * CURRENTLY stored, so this request can no longer race a concurrent
+   * Save no matter which one lands last.
    */
   const ringMutation = useMutation({
     mutationFn: async (next: {
       selectedScoreRings: ScoreRingId[];
       heroRingOrder: HeroRingId[];
     }) => {
-      if (!remote) throw new Error("layout not loaded");
-      return apiPut<DashboardLayout>("/api/dashboard/widgets", {
-        ...remote,
-        selectedScoreRings: next.selectedScoreRings,
-        heroRingOrder: next.heroRingOrder,
-      });
+      return apiPut<DashboardLayout>(
+        "/api/dashboard/widgets",
+        buildRingMutationPayload(next),
+      );
     },
     onMutate: async (next) => {
       await queryClient.cancelQueries({
diff --git a/src/lib/__tests__/dashboard-layout.test.ts b/src/lib/__tests__/dashboard-layout.test.ts
index 8379f5c0c..0e091ce05 100644
--- a/src/lib/__tests__/dashboard-layout.test.ts
+++ b/src/lib/__tests__/dashboard-layout.test.ts
@@ -13,6 +13,7 @@ import {
   PRESERVED_LAYOUT_FIELDS,
   layoutNeedsPreserveRead,
   mergePreservedLayoutFields,
+  buildRingMutationPayload,
   type DashboardLayout,
 } from "@/lib/dashboard-layout";
 
@@ -1006,20 +1007,24 @@ describe("layout field merge disposition", () => {
     }
   });
 
-  it("preserves comparisonBaseline alongside the other client-owned fields", () => {
+  it("preserves comparisonBaseline and widgets alongside the other client-owned fields", () => {
     // The regression itself: `comparisonBaseline` must be in the preserve
-    // set, not merely present in the disposition map.
+    // set, not merely present in the disposition map. `widgets` joined it in
+    // v1.32.1 (issue #581) — see the dedicated describe block below.
     expect([...PRESERVED_LAYOUT_FIELDS].sort()).toEqual([
       "chartOverlayPrefs",
       "comparisonBaseline",
       "heroRingOrder",
       "selectedScoreRings",
+      "widgets",
     ]);
   });
 
-  it("replaces the fields the request itself owns", () => {
+  it("replaces only the field every request must state", () => {
+    // `version` is the sole `"replace"` field left once `widgets` joined
+    // the preserve set — a PUT that omits it is rejected by Zod, so there
+    // is never a stored value to fall back to.
     expect(LAYOUT_FIELD_MERGE_DISPOSITION.version).toBe("replace");
-    expect(LAYOUT_FIELD_MERGE_DISPOSITION.widgets).toBe("replace");
   });
 
   it("skips the stored-layout read when the client sent every preserved field", () => {
@@ -1086,3 +1091,51 @@ describe("layout field merge disposition", () => {
     expect(merged.widgets).toEqual(fullyPopulatedLayout.widgets);
   });
 });
+
+/**
+ * v1.32.1 — regression for issue #581 (dashboard layout race). The
+ * Settings page's instant score-ring PUT used to resend the FULL layout,
+ * built from the `remote` query-cache snapshot
+ * (`{...remote, selectedScoreRings, heroRingOrder}`). That snapshot can be
+ * stale relative to an in-flight or already-committed tile/chart Save;
+ * because `widgets` was a `"replace"`-disposition field on the server, an
+ * explicitly-present stale copy always won on write and silently reverted
+ * the just-saved layout.
+ *
+ * `buildRingMutationPayload` is the exact function
+ * `ringMutation.mutationFn` (in `dashboard-layout-section.tsx`) calls to
+ * build its request body. Pinning its shape here — no `widgets`, no
+ * `comparisonBaseline`, no `chartOverlayPrefs` — is what makes the race
+ * structurally impossible: a payload that never carries those fields
+ * cannot overwrite them no matter which request lands last. See
+ * `src/app/api/dashboard/widgets/__tests__/route.test.ts` for the
+ * server-side half — a PUT shaped like this preserves whatever layout is
+ * CURRENTLY stored, not a client-held snapshot.
+ */
+describe("buildRingMutationPayload — instant score-ring PUT payload (regression #581)", () => {
+  it("carries only version + the two ring fields", () => {
+    const payload = buildRingMutationPayload({
+      selectedScoreRings: ["READINESS"],
+      heroRingOrder: ["HEALTH_SCORE", "READINESS"],
+    });
+    expect(Object.keys(payload).sort()).toEqual([
+      "heroRingOrder",
+      "selectedScoreRings",
+      "version",
+    ]);
+    expect(payload.version).toBe(1);
+    expect(payload.selectedScoreRings).toEqual(["READINESS"]);
+    expect(payload.heroRingOrder).toEqual(["HEALTH_SCORE", "READINESS"]);
+  });
+
+  it("never includes widgets, comparisonBaseline, or chartOverlayPrefs — the fields a concurrent Save owns", () => {
+    const payload = buildRingMutationPayload({
+      selectedScoreRings: ["READINESS"],
+      heroRingOrder: ["HEALTH_SCORE", "READINESS"],
+    });
+    expect(payload.widgets).toBeUndefined();
+    expect(payload.comparisonBaseline).toBeUndefined();
+    expect(payload.chartOverlayPrefs).toBeUndefined();
+    expect("widgets" in payload).toBe(false);
+  });
+});
diff --git a/src/lib/dashboard-layout.ts b/src/lib/dashboard-layout.ts
index 54447cc5d..4c4e790a4 100644
--- a/src/lib/dashboard-layout.ts
+++ b/src/lib/dashboard-layout.ts
@@ -574,8 +574,8 @@ export interface DashboardLayout {
  * omits it.
  *
  * - `"replace"` — the field is the point of the request. A PUT that omits it
- *   is either rejected by Zod (`version`, `widgets` are required) or means
- *   the caller genuinely has nothing to say.
+ *   is rejected by Zod (`version` is required) — the caller always has
+ *   something to say about a `"replace"` field.
  * - `"preserve"` — the field is owned by a surface OTHER than the one making
  *   this request, so an omission means "I don't know about this", never
  *   "clear it". The route reads the stored layout and carries the existing
@@ -591,6 +591,18 @@ export interface DashboardLayout {
  * clamps a missing value to `"none"`, so every native layout save wiped the
  * baseline the user had picked on the web.
  *
+ * `widgets` moved from `"replace"` to `"preserve"` in v1.32.1 (issue #581).
+ * The Settings page's instant score-ring toggle used to resend the FULL
+ * layout — including `widgets` — built from the query cache's `remote`
+ * snapshot. That snapshot can be stale by the time the ring request lands:
+ * if a normal tile/chart Save committed a newer layout first, the
+ * ring request's explicit (present, not omitted) stale `widgets` value
+ * still won on write and silently reverted the just-saved layout. Making
+ * `widgets` optional + preserve-when-absent lets the ring mutation omit it
+ * entirely, so the field it never touches can no longer race a concurrent
+ * Save — the route always carries forward whatever is CURRENTLY stored,
+ * not a client-held copy.
+ *
  * `satisfies Record<keyof DashboardLayout, …>` is the load-bearing part.
  * Adding a field to `DashboardLayout` without adding it here is a TYPE error,
  * so the next field cannot repeat the `comparisonBaseline` mistake by
@@ -598,7 +610,7 @@ export interface DashboardLayout {
  */
 export const LAYOUT_FIELD_MERGE_DISPOSITION = {
   version: "replace",
-  widgets: "replace",
+  widgets: "preserve",
   comparisonBaseline: "preserve",
   chartOverlayPrefs: "preserve",
   selectedScoreRings: "preserve",
@@ -647,6 +659,38 @@ export function mergePreservedLayoutFields(
   return merged;
 }
 
+/**
+ * v1.32.1 — pure payload builder for the Settings page's instant score-ring
+ * PUT (`ringMutation` in `dashboard-layout-section.tsx`). Lives in this
+ * client-safe module (imported by both the client component and the server
+ * route already) rather than the "use client" component file, so a
+ * server-side regression test can import it without pulling the component's
+ * UI dependency graph across the client/server boundary — see
+ * `src/app/api/dashboard/widgets/__tests__/route.test.ts`.
+ *
+ * Deliberately returns ONLY the ring fields (plus `version`) — no
+ * `widgets`, `comparisonBaseline`, or `chartOverlayPrefs`. Before v1.32.1 the
+ * ring mutation resent the FULL layout built from the client's `remote`
+ * query-cache snapshot, which can be stale by the time the request lands: if
+ * a normal tile/chart Save committed a newer layout first, the ring
+ * request's explicit — present, not omitted — stale `widgets` still won on
+ * write and silently reverted the just-saved layout (issue #581). Those
+ * three fields are all `"preserve"`-disposition here
+ * (`LAYOUT_FIELD_MERGE_DISPOSITION`): omitting them means the route always
+ * carries forward whatever is CURRENTLY stored, so this payload can no
+ * longer race a concurrent Save no matter which request lands last.
+ */
+export function buildRingMutationPayload(next: {
+  selectedScoreRings: ScoreRingId[];
+  heroRingOrder: HeroRingId[];
+}): Partial<DashboardLayout> {
+  return {
+    version: DASHBOARD_LAYOUT_VERSION,
+    selectedScoreRings: next.selectedScoreRings,
+    heroRingOrder: next.heroRingOrder,
+  };
+}
+
 const DASHBOARD_LAYOUT_VERSION = 1;
 
 /**

From 1371bb1cf9d33c80d096e02abe082f7c8d077489 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Bombeck?= <mbombeck@gmail.com>
Date: Thu, 23 Jul 2026 09:25:16 +0200
Subject: [PATCH 2/5] fix(measurement-reminders): recompute nextDueAt from the
 field actually set, not a nullish fallback
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

PATCH /api/measurement-reminders/{id} persisted an explicit null cadence
clear correctly, but the immediate nextDueAt recomputation merged fields
with `updateValue ?? existingValue` — a JSON null and an omitted field
are both nullish, so the merge silently fell back to the OLD cadence for
one cycle. This hit interval-to-RRULE and RRULE-to-interval transitions
and an explicit anchorDate clear alike.

The merge now keys off Object.hasOwn(updateData, field): updateData
already encodes exactly which fields are being persisted, including the
mutual-exclusivity auto-clear (setting one cadence nulls the other), so
recomputation can never diverge from what the row ends up holding.
---
 .../[id]/__tests__/route.test.ts              | 229 ++++++++++++++++++
 .../api/measurement-reminders/[id]/route.ts   |  35 ++-
 2 files changed, 255 insertions(+), 9 deletions(-)
 create mode 100644 src/app/api/measurement-reminders/[id]/__tests__/route.test.ts

diff --git a/src/app/api/measurement-reminders/[id]/__tests__/route.test.ts b/src/app/api/measurement-reminders/[id]/__tests__/route.test.ts
new file mode 100644
index 000000000..1a9ac856f
--- /dev/null
+++ b/src/app/api/measurement-reminders/[id]/__tests__/route.test.ts
@@ -0,0 +1,229 @@
+/**
+ * v1.32.1 — regression for iOS coordination issue #62: the `nextDueAt`
+ * recomputation on `PATCH /api/measurement-reminders/{id}` used to read an
+ * explicit `null` cadence clear as "field omitted" (`?? existing.field`
+ * cannot distinguish the two — both are nullish) and recompute against the
+ * STALE cadence for one cycle, even though the persisted row itself already
+ * carried the correct cleared value.
+ *
+ * Every test below drives the REAL `computeReminderNextDueAt` (not a mock)
+ * so the "correct" and "stale" comparison values are genuine recurrence-
+ * engine output, not hand-picked dates — and asserts the fixtures actually
+ * differ before trusting the route's answer, so a fixture collision can't
+ * hide a regression.
+ */
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { NextRequest } from "next/server";
+
+vi.mock("@/lib/api-handler", () => ({
+  apiHandler: <T extends (...args: unknown[]) => unknown>(fn: T) => fn,
+  requireAuth: vi.fn(async () => ({ user: { id: "u1", locale: "en" } })),
+}));
+
+vi.mock("@/lib/auth/audit", () => ({
+  auditLog: vi.fn().mockResolvedValue(undefined),
+}));
+
+vi.mock("@/lib/logging/context", () => ({ annotate: vi.fn() }));
+
+const findFirstMock = vi.fn();
+const updateMock = vi.fn();
+const findUserMock = vi.fn();
+const auditLogCreateMock = vi.fn();
+vi.mock("@/lib/db", () => ({
+  prisma: {
+    measurementReminder: {
+      findFirst: (...a: unknown[]) => findFirstMock(...a),
+      update: (...a: unknown[]) => updateMock(...a),
+    },
+    user: { findUnique: (...a: unknown[]) => findUserMock(...a) },
+    auditLog: { create: (...a: unknown[]) => auditLogCreateMock(...a) },
+  },
+}));
+
+import { PATCH } from "../route";
+import { computeReminderNextDueAt } from "@/lib/measurement-reminders/scheduling";
+
+const BASE_ROW = {
+  id: "r1",
+  userId: "u1",
+  label: "Blutdruck messen",
+  measurementType: "BLOOD_PRESSURE_SYS",
+  intervalDays: 30,
+  rrule: null as string | null,
+  anchorDate: null as Date | null,
+  endsOn: null,
+  origin: "VORSORGE",
+  notifyHour: 9,
+  location: null,
+  nextDueAt: new Date("2026-01-31T09:00:00Z"),
+  lastSatisfiedAt: null as Date | null,
+  enabled: true,
+  createdAt: new Date("2026-01-01T00:00:00Z"),
+  updatedAt: new Date("2026-01-01T00:00:00Z"),
+  deletedAt: null,
+};
+
+const NOW = new Date("2026-06-15T08:00:00.000Z");
+const TZ = "Europe/Berlin";
+
+function makeRequest(body: unknown): NextRequest {
+  return new NextRequest("http://localhost/api/measurement-reminders/r1", {
+    method: "PATCH",
+    headers: { "content-type": "application/json" },
+    body: JSON.stringify(body),
+  });
+}
+
+const params = { params: Promise.resolve({ id: "r1" }) };
+
+beforeEach(() => {
+  vi.clearAllMocks();
+  findUserMock.mockResolvedValue({ timezone: TZ });
+  updateMock.mockImplementation(
+    async ({ data }: { data: Record<string, unknown> }) => ({
+      ...BASE_ROW,
+      ...data,
+    }),
+  );
+  vi.useFakeTimers();
+  vi.setSystemTime(NOW);
+});
+
+afterEach(() => {
+  vi.useRealTimers();
+});
+
+describe("PATCH /api/measurement-reminders/[id] — nextDueAt honours explicit-null cadence clears (regression iOS #62)", () => {
+  it("interval → RRULE: recomputes off the NEW rrule, not the just-cleared interval", async () => {
+    // Existing rolling reminder: intervalDays=30, rrule=null.
+    findFirstMock.mockResolvedValue(BASE_ROW);
+
+    const res = await PATCH(
+      makeRequest({ intervalDays: null, rrule: "FREQ=YEARLY" }),
+      params,
+    );
+    expect(res.status).toBe(200);
+
+    const persisted = updateMock.mock.calls[0]?.[0]?.data as Record<
+      string,
+      unknown
+    >;
+    // The explicit-null clear + the new rrule both persist correctly —
+    // this half was never broken.
+    expect(persisted.intervalDays).toBeNull();
+    expect(persisted.rrule).toBe("FREQ=YEARLY");
+
+    const correct = computeReminderNextDueAt(
+      { ...BASE_ROW, intervalDays: null, rrule: "FREQ=YEARLY" },
+      TZ,
+      NOW,
+    );
+    // The bug: `?? existing` reads the cleared intervalDays as "omitted"
+    // and recomputes against the OLD rolling cadence for one cycle.
+    const staleBug = computeReminderNextDueAt(
+      { ...BASE_ROW, intervalDays: 30, rrule: null },
+      TZ,
+      NOW,
+    );
+    // Mutation-check guard: the fixtures must actually diverge, or this
+    // test can't tell a fix from a no-op.
+    expect(correct).not.toEqual(staleBug);
+
+    expect(persisted.nextDueAt).toEqual(correct);
+    expect(persisted.nextDueAt).not.toEqual(staleBug);
+  });
+
+  it("RRULE → interval: recomputes off the NEW interval, not the just-cleared rrule (incl. its BYHOUR)", async () => {
+    findFirstMock.mockResolvedValue({
+      ...BASE_ROW,
+      intervalDays: null,
+      rrule: "FREQ=DAILY;BYHOUR=7,19",
+    });
+
+    const res = await PATCH(
+      makeRequest({ rrule: null, intervalDays: 14 }),
+      params,
+    );
+    expect(res.status).toBe(200);
+
+    const persisted = updateMock.mock.calls[0]?.[0]?.data as Record<
+      string,
+      unknown
+    >;
+    expect(persisted.rrule).toBeNull();
+    expect(persisted.intervalDays).toBe(14);
+
+    const correct = computeReminderNextDueAt(
+      { ...BASE_ROW, intervalDays: 14, rrule: null },
+      TZ,
+      NOW,
+    );
+    const staleBug = computeReminderNextDueAt(
+      { ...BASE_ROW, intervalDays: null, rrule: "FREQ=DAILY;BYHOUR=7,19" },
+      TZ,
+      NOW,
+    );
+    expect(correct).not.toEqual(staleBug);
+
+    expect(persisted.nextDueAt).toEqual(correct);
+    expect(persisted.nextDueAt).not.toEqual(staleBug);
+  });
+
+  it("explicit anchorDate: null clear recomputes off no-anchor, not the stale anchor", async () => {
+    findFirstMock.mockResolvedValue({
+      ...BASE_ROW,
+      intervalDays: 30,
+      anchorDate: new Date("2026-01-15T00:00:00Z"),
+    });
+
+    const res = await PATCH(makeRequest({ anchorDate: null }), params);
+    expect(res.status).toBe(200);
+
+    const persisted = updateMock.mock.calls[0]?.[0]?.data as Record<
+      string,
+      unknown
+    >;
+    expect(persisted.anchorDate).toBeNull();
+
+    const correct = computeReminderNextDueAt(
+      { ...BASE_ROW, intervalDays: 30, anchorDate: null },
+      TZ,
+      NOW,
+    );
+    const staleBug = computeReminderNextDueAt(
+      {
+        ...BASE_ROW,
+        intervalDays: 30,
+        anchorDate: new Date("2026-01-15T00:00:00Z"),
+      },
+      TZ,
+      NOW,
+    );
+    expect(correct).not.toEqual(staleBug);
+
+    expect(persisted.nextDueAt).toEqual(correct);
+    expect(persisted.nextDueAt).not.toEqual(staleBug);
+  });
+
+  it("omitted cadence fields on a label-only edit leave the cadence — and nextDueAt — unchanged", async () => {
+    findFirstMock.mockResolvedValue(BASE_ROW);
+
+    const res = await PATCH(makeRequest({ label: "New label" }), params);
+    expect(res.status).toBe(200);
+
+    const persisted = updateMock.mock.calls[0]?.[0]?.data as Record<
+      string,
+      unknown
+    >;
+    expect(persisted.label).toBe("New label");
+    // The cadence keys are never written at all on a label-only edit — no
+    // clear, no touch.
+    expect("intervalDays" in persisted).toBe(false);
+    expect("rrule" in persisted).toBe(false);
+    expect("anchorDate" in persisted).toBe(false);
+
+    const expected = computeReminderNextDueAt(BASE_ROW, TZ, NOW);
+    expect(persisted.nextDueAt).toEqual(expected);
+  });
+});
diff --git a/src/app/api/measurement-reminders/[id]/route.ts b/src/app/api/measurement-reminders/[id]/route.ts
index b163194a6..aad5e46e0 100644
--- a/src/app/api/measurement-reminders/[id]/route.ts
+++ b/src/app/api/measurement-reminders/[id]/route.ts
@@ -133,18 +133,35 @@ export const PATCH = apiHandler(
     // Recompute next-due against the merged cadence. Floor the search at
     // the last-satisfied instant (or now) so a cadence edit re-anchors
     // cleanly off the user's last fulfilment.
+    //
+    // v1.32.1 — `Object.hasOwn(updateData, field)` replaces a `?? existing`
+    // fallback here (issue #62). `??` cannot tell an explicit `null` clear
+    // apart from an omitted field — both are nullish — so a PATCH that
+    // cleared `intervalDays` to switch a reminder onto an RRULE still
+    // recomputed `nextDueAt` against the OLD rolling interval for one
+    // cycle (rolling cadence wins the dispatcher's precedence order, so the
+    // stale interval silently overrode the just-set RRULE). The same gap
+    // hit the RRULE → interval direction and an explicit `anchorDate: null`
+    // clear. `updateData` already encodes the field-by-field truth of what
+    // is ACTUALLY being persisted — including the mutual-exclusivity
+    // auto-clear a few lines up — so keying off its own keys (present, even
+    // when the value is `null`) can never diverge from what the database
+    // ends up holding.
     const timezone = await resolveTimezone(user.id);
     const now = new Date();
     const merged: ReminderScheduleInput = {
-      intervalDays:
-        (updateData.intervalDays as number | null | undefined) ??
-        existing.intervalDays,
-      rrule: (updateData.rrule as string | null | undefined) ?? existing.rrule,
-      anchorDate:
-        (updateData.anchorDate as Date | null | undefined) ??
-        existing.anchorDate,
-      notifyHour:
-        (updateData.notifyHour as number | undefined) ?? existing.notifyHour,
+      intervalDays: Object.hasOwn(updateData, "intervalDays")
+        ? (updateData.intervalDays as number | null)
+        : existing.intervalDays,
+      rrule: Object.hasOwn(updateData, "rrule")
+        ? (updateData.rrule as string | null)
+        : existing.rrule,
+      anchorDate: Object.hasOwn(updateData, "anchorDate")
+        ? (updateData.anchorDate as Date | null)
+        : existing.anchorDate,
+      notifyHour: Object.hasOwn(updateData, "notifyHour")
+        ? (updateData.notifyHour as number)
+        : existing.notifyHour,
       lastSatisfiedAt: existing.lastSatisfiedAt,
       createdAt: existing.createdAt,
       // v1.18.1 — preserve the course window so an edit of a finite

From d750c1827e07b5d93021cd982da31880fdef9a69 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Bombeck?= <mbombeck@gmail.com>
Date: Thu, 23 Jul 2026 09:28:39 +0200
Subject: [PATCH 3/5] fix(settings): stop ntfy PUT from clearing the stored
 auth token on unrelated edits
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

PUT /api/settings/ntfy reconstructed the entire stored config from the
request body. GET never returns the write-only authToken (only
hasAuthToken), so clients correctly omit it on any edit that doesn't
touch the credential — but the route treated an omitted or empty token
as "clear it", silently destroying a working notification credential on
routine edits like toggling enabled.

An omitted or empty authToken now preserves the currently stored value;
only a non-empty value replaces it. Mirrors the identical headerValue
preserve-on-empty contract already shipped on the webhook channel route.
---
 .../__tests__/channel-enabled-routes.test.ts  | 118 ++++++++++++++++++
 src/app/api/settings/ntfy/route.ts            |  23 +++-
 2 files changed, 140 insertions(+), 1 deletion(-)

diff --git a/src/app/api/settings/__tests__/channel-enabled-routes.test.ts b/src/app/api/settings/__tests__/channel-enabled-routes.test.ts
index c5cc73548..c09dc31e9 100644
--- a/src/app/api/settings/__tests__/channel-enabled-routes.test.ts
+++ b/src/app/api/settings/__tests__/channel-enabled-routes.test.ts
@@ -298,3 +298,121 @@ describe("notification channel enable-only routes", () => {
     },
   );
 });
+
+/**
+ * v1.32.1 — regression for iOS coordination issue #63: `PUT
+ * /api/settings/ntfy` reconstructed the entire stored config from the
+ * request body. `GET` never returns the write-only `authToken` (only
+ * `hasAuthToken: true/false`), so both native and web clients correctly
+ * OMIT — or round-trip an empty string through — the field on any
+ * unrelated edit. Rebuilding `config` without a preserve fallback
+ * silently dropped a working token on the next save.
+ *
+ * The fix mirrors the pre-existing `headerValue` preserve-on-empty
+ * contract in `src/app/api/settings/webhook/route.ts` (asserted here too,
+ * as a parity pin — that route was never broken, but any future drift
+ * between the two should fail the same suite). Covers exactly the four
+ * cases the report asks for.
+ */
+describe("PUT /api/settings/ntfy — write-only authToken preserve-on-omit contract", () => {
+  function upsertConfig() {
+    const call = vi.mocked(prisma.notificationChannel.upsert).mock
+      .calls[0]?.[0] as {
+      create: { config: string };
+      update: { config: string };
+    };
+    // The route always upserts — assert both arms agree, then decode one.
+    expect(call.update.config).toBe(call.create.config);
+    return JSON.parse(call.update.config.replace(/^encrypted:/, "")) as {
+      serverUrl: string;
+      topic: string;
+      authToken?: string;
+    };
+  }
+
+  it("an omitted authToken preserves the stored secret", async () => {
+    vi.mocked(prisma.notificationChannel.findUnique).mockResolvedValue({
+      config:
+        'encrypted:{"serverUrl":"https://ntfy.sh","topic":"saved-topic","authToken":"secret"}',
+    } as never);
+
+    const response = await put("ntfy", {
+      serverUrl: "https://ntfy.sh",
+      topic: "saved-topic",
+      enabled: true,
+    });
+
+    expect(response.status).toBe(200);
+    expect(upsertConfig().authToken).toBe("secret");
+  });
+
+  it("an explicit empty-string authToken preserves the stored secret (matches current clients)", async () => {
+    vi.mocked(prisma.notificationChannel.findUnique).mockResolvedValue({
+      config:
+        'encrypted:{"serverUrl":"https://ntfy.sh","topic":"saved-topic","authToken":"secret"}',
+    } as never);
+
+    const response = await put("ntfy", {
+      serverUrl: "https://ntfy.sh",
+      topic: "saved-topic",
+      authToken: "",
+      enabled: true,
+    });
+
+    expect(response.status).toBe(200);
+    expect(upsertConfig().authToken).toBe("secret");
+  });
+
+  it("a non-empty authToken replaces the stored secret", async () => {
+    vi.mocked(prisma.notificationChannel.findUnique).mockResolvedValue({
+      config:
+        'encrypted:{"serverUrl":"https://ntfy.sh","topic":"saved-topic","authToken":"old-secret"}',
+    } as never);
+
+    const response = await put("ntfy", {
+      serverUrl: "https://ntfy.sh",
+      topic: "saved-topic",
+      authToken: "new-secret",
+      enabled: true,
+    });
+
+    expect(response.status).toBe(200);
+    expect(upsertConfig().authToken).toBe("new-secret");
+  });
+
+  it("creating without a token remains valid where anonymous ntfy is allowed", async () => {
+    vi.mocked(prisma.notificationChannel.findUnique).mockResolvedValue(null);
+
+    const response = await put("ntfy", {
+      serverUrl: "https://ntfy.sh",
+      topic: "public-topic",
+      enabled: false,
+    });
+
+    expect(response.status).toBe(200);
+    const config = upsertConfig();
+    expect(config.authToken).toBeUndefined();
+    expect(config.topic).toBe("public-topic");
+  });
+
+  it("parity pin: the webhook headerValue preserve-on-empty contract this fix mirrors is intact", async () => {
+    vi.mocked(prisma.notificationChannel.findUnique).mockResolvedValue({
+      config:
+        'encrypted:{"url":"https://saved.example/hook","headerName":"Authorization","headerValue":"secret"}',
+    } as never);
+
+    const response = await put("webhook", {
+      url: "https://saved.example/hook",
+      headerName: "Authorization",
+      enabled: true,
+    });
+
+    expect(response.status).toBe(200);
+    const call = vi.mocked(prisma.notificationChannel.upsert).mock
+      .calls[0]?.[0] as { update: { config: string } };
+    const config = JSON.parse(
+      call.update.config.replace(/^encrypted:/, ""),
+    ) as { headerValue?: string };
+    expect(config.headerValue).toBe("secret");
+  });
+});
diff --git a/src/app/api/settings/ntfy/route.ts b/src/app/api/settings/ntfy/route.ts
index 0d916384f..f9dc4f043 100644
--- a/src/app/api/settings/ntfy/route.ts
+++ b/src/app/api/settings/ntfy/route.ts
@@ -113,10 +113,31 @@ export const PUT = apiHandler(async (request: NextRequest) => {
     );
   }
 
+  // v1.32.1 — preserve an existing auth token when the client sends an
+  // empty one (issue #63). GET never returns the secret (`hasAuthToken`
+  // only), so both native and web clients correctly omit — or round-trip
+  // an empty string through — the field on any unrelated edit (e.g.
+  // toggling `enabled`). Reconstructing `config` from scratch without this
+  // fallback silently dropped the token on every such save. Mirrors the
+  // identical `headerValue` preserve-on-empty contract in
+  // `src/app/api/settings/webhook/route.ts`. A non-empty value replaces it.
+  let nextAuthToken = authToken || undefined;
+  if (!nextAuthToken) {
+    const existing = await prisma.notificationChannel.findUnique({
+      where: { userId_type: { userId: user.id, type: "NTFY" } },
+    });
+    if (existing) {
+      const prev = JSON.parse(decrypt(existing.config)) as {
+        authToken?: string;
+      };
+      nextAuthToken = prev.authToken || undefined;
+    }
+  }
+
   const config = JSON.stringify({
     serverUrl: serverUrl || "https://ntfy.sh",
     topic: topic || "",
-    ...(authToken ? { authToken } : {}),
+    ...(nextAuthToken ? { authToken: nextAuthToken } : {}),
   });
 
   const encryptedConfig = encrypt(config);

From 9ef3207cb65dfe7d10fa0486fa2d22bdcfff4bca Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Bombeck?= <mbombeck@gmail.com>
Date: Thu, 23 Jul 2026 09:38:24 +0200
Subject: [PATCH 4/5] style: run prettier on the dashboard-layout-section test
 file

---
 .../settings/__tests__/dashboard-layout-section.test.tsx     | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/components/settings/__tests__/dashboard-layout-section.test.tsx b/src/components/settings/__tests__/dashboard-layout-section.test.tsx
index 33eaa1ea4..4594cd1f6 100644
--- a/src/components/settings/__tests__/dashboard-layout-section.test.tsx
+++ b/src/components/settings/__tests__/dashboard-layout-section.test.tsx
@@ -69,7 +69,10 @@ vi.mock("@/hooks/use-auth", () => ({
 }));
 
 import { I18nProvider } from "@/lib/i18n/context";
-import { DashboardLayoutSection, reorderWidgets } from "../dashboard-layout-section";
+import {
+  DashboardLayoutSection,
+  reorderWidgets,
+} from "../dashboard-layout-section";
 
 function render(node: React.ReactElement, locale: "en" | "de" = "en") {
   return renderToStaticMarkup(

From 32edb033e861f577bb5858a77e73c87f04934b44 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Bombeck?= <mbombeck@gmail.com>
Date: Thu, 23 Jul 2026 09:39:46 +0200
Subject: [PATCH 5/5] docs: note the three silent-data-loss fixes in the
 changelog

---
 CHANGELOG.md | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a15813119..a7b46af27 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,21 @@
 
 ## [Unreleased]
 
+- **Dashboard layout changes can no longer be reverted by a concurrent
+  score-ring save.** The instant score-ring toggle now sends only the ring
+  fields instead of resending a cached snapshot of the whole layout, closing
+  a race where an in-flight ring update could land after a tile/chart Save
+  and silently restore the older layout.
+- **Measurement-reminder cadence edits recompute against the cadence that
+  was actually saved.** Clearing `intervalDays` or `rrule` to switch a
+  reminder's schedule no longer leaves the next-due date computed off the
+  just-replaced value for one cycle.
+- **ntfy notification settings keep a saved auth token across unrelated
+  edits.** Toggling the channel, or editing the server URL or topic, no
+  longer silently clears a previously configured token.
+
+No migrations. No breaking changes.
+
 ## [1.32.0] — 2026-07-22
 
 - **Provider ingestion and daily reactions now preserve the correct identity.**