diff --git a/src/app/api/insights/generate/__tests__/route.test.ts b/src/app/api/insights/generate/__tests__/route.test.ts
index beb2ff51b..938d27bbb 100644
--- a/src/app/api/insights/generate/__tests__/route.test.ts
+++ b/src/app/api/insights/generate/__tests__/route.test.ts
@@ -77,7 +77,6 @@ vi.mock("@/lib/insights/features", () => ({
 }));
 
 vi.mock("@/lib/insights/prompt", () => ({
-  getInsightsSystemPrompt: vi.fn(() => "system"),
   buildUserPrompt: vi.fn(() => "user"),
 }));
 
diff --git a/src/components/charts/medication-compliance-chart.tsx b/src/components/charts/medication-compliance-chart.tsx
index 674aa1089..081495c57 100644
--- a/src/components/charts/medication-compliance-chart.tsx
+++ b/src/components/charts/medication-compliance-chart.tsx
@@ -191,7 +191,15 @@ interface MedicationComplianceChartProps {
 export function MedicationComplianceChart({
   title,
   userTimezone = "Europe/Berlin",
+  compareBaseline,
 }: MedicationComplianceChartProps) {
+  // v1.4.27 R4 RC3 — the prop is accepted so the dashboard can pass
+  // `compareBaseline={compareBaseline}` uniformly across every chart.
+  // The comparison overlay itself is deferred: medication compliance is
+  // a percentage-of-doses metric whose prior-period overlay needs a
+  // second window of intake events. Discard explicitly so the
+  // destructure is intentional rather than a missed wire-up.
+  void compareBaseline;
   const { isAuthenticated } = useAuth();
   const { t, locale } = useTranslations();
   const fmt = useFormatters();
diff --git a/src/components/insights/__tests__/hero-strip.test.tsx b/src/components/insights/__tests__/hero-strip.test.tsx
index e6d3a7ea5..35f748a20 100644
--- a/src/components/insights/__tests__/hero-strip.test.tsx
+++ b/src/components/insights/__tests__/hero-strip.test.tsx
@@ -5,11 +5,9 @@ import { HeroStrip } from "../hero-strip";
 import type { DailyBriefing as DailyBriefingPayload } from "@/lib/ai/schema";
 
 /**
- * v1.4.20 phase B1 — Insights hero strip.
- *
- * Replaces v1.4.16 `<InsightsPageHero>`. Pinning the slots so future
- * polish can't silently drop the greeting / subtitle / action row /
- * suggested-prompt strip.
+ * Insights hero strip — pins the slots so future polish can't
+ * silently drop the greeting / subtitle / action row / suggested-
+ * prompt strip.
  */
 
 function render(node: React.ReactNode, locale: "en" | "de" = "en") {
diff --git a/src/components/insights/hero-strip.tsx b/src/components/insights/hero-strip.tsx
index 413f72a5a..2f3d84e95 100644
--- a/src/components/insights/hero-strip.tsx
+++ b/src/components/insights/hero-strip.tsx
@@ -15,10 +15,10 @@ import {
 import type { DailyBriefing as DailyBriefingPayload } from "@/lib/ai/schema";
 
 /**
- * v1.4.20 phase B1 — Insights redesign hero strip.
+ * Insights redesign hero strip.
  *
- * Replaces the v1.4.16 `<InsightsPageHero>` with the wider band from
- * the design handoff (`prototype/artboard-fullpage.jsx → BriefingHero`):
+ * The wider band lifted from the design handoff
+ * (`prototype/artboard-fullpage.jsx → BriefingHero`):
  *
  *   - locale-aware time-of-day greeting line ("Good morning, …" /
  *     "Guten Morgen, …") + a narrative subtitle (the briefing
diff --git a/src/lib/ai/coach/glp1-snapshot.ts b/src/lib/ai/coach/glp1-snapshot.ts
index 3fb131689..bda039927 100644
--- a/src/lib/ai/coach/glp1-snapshot.ts
+++ b/src/lib/ai/coach/glp1-snapshot.ts
@@ -410,10 +410,3 @@ export async function buildGlp1SnapshotBlock(
   };
 }
 
-/** Exported for tests. */
-export const __testables = {
-  deriveDrugNames,
-  parseTagList,
-  parseDaysOfWeek,
-  predictNextInjection,
-};
diff --git a/src/lib/ai/coach/persistence.ts b/src/lib/ai/coach/persistence.ts
index d4ae22537..22a6141e5 100644
--- a/src/lib/ai/coach/persistence.ts
+++ b/src/lib/ai/coach/persistence.ts
@@ -317,10 +317,3 @@ export async function deleteConversation(
   return true;
 }
 
-/**
- * Count assistant + user turns in one conversation. Used by the
- * 20-turn cap before a summarise-and-restart pass.
- */
-export async function countMessages(conversationId: string): Promise<number> {
-  return prisma.coachMessage.count({ where: { conversationId } });
-}
diff --git a/src/lib/ai/prompts/general-status.ts b/src/lib/ai/prompts/general-status.ts
index 357be131d..fb4c5b604 100644
--- a/src/lib/ai/prompts/general-status.ts
+++ b/src/lib/ai/prompts/general-status.ts
@@ -72,41 +72,3 @@ Fokussiere auf das Zusammenspiel der verschiedenen Parameter und identifiziere d
 ${snapshotJson}`;
 }
 
-// Backward-compatible export for insights/generate route (Task 8 uses this)
-export function buildGeneratePrompts(
-  featuresJson: string,
-  privacyMode: string,
-  locale: Locale,
-): { systemPrompt: string; userPrompt: string } {
-  if (locale === "en") {
-    const modeLabel =
-      privacyMode === "raw"
-        ? "Aggregated data + raw values (entire available period, anonymised)"
-        : "Aggregated data only (no exact timestamps or raw values)";
-
-    return {
-      systemPrompt: getGeneralStatusSystemPrompt(locale),
-      userPrompt: `Analyse the following health data.
-Data mode: ${modeLabel}
-Use each metric's coverage object for measurement frequency and time spans.
-Use correlations for cross-metric analysis and historicalComparison for temporal context.
-
-${featuresJson}`,
-    };
-  }
-
-  const modeLabel =
-    privacyMode === "raw"
-      ? "Aggregierte Daten + Rohdaten (gesamter verfügbarer Zeitraum, anonymisiert)"
-      : "Nur aggregierte Daten (keine exakten Zeitstempel oder Rohwerte)";
-
-  return {
-    systemPrompt: getGeneralStatusSystemPrompt(locale),
-    userPrompt: `Analysiere die folgenden Gesundheitsdaten.
-Datenmodus: ${modeLabel}
-Beachte die coverage-Objekte jeder Metrik für Informationen zu Messhäufigkeit und Zeiträumen.
-Nutze die correlations-Daten für Kreuzanalysen und historicalComparison für temporale Einordnung.
-
-${featuresJson}`,
-  };
-}
diff --git a/src/lib/ai/prompts/insight-generator.ts b/src/lib/ai/prompts/insight-generator.ts
index 6924d71d7..095580d8a 100644
--- a/src/lib/ai/prompts/insight-generator.ts
+++ b/src/lib/ai/prompts/insight-generator.ts
@@ -714,8 +714,7 @@ const INSIGHTS_LOCALE_REPLY_FOOTER_FALLBACK: Record<
 
 /**
  * Returns the active scope-hardened system prompt for a given locale.
- * Use this in place of the legacy `getInsightsSystemPrompt` once the
- * route migrates to `generateInsight()` (planned v1.4.16).
+ * The route consumes this via `generateInsight()`.
  */
 export function getStrictInsightsSystemPrompt(locale: Locale): string {
   if (locale === "de") return SYSTEM_PROMPT_DE;
diff --git a/src/lib/ai/prompts/safety-contracts.ts b/src/lib/ai/prompts/safety-contracts.ts
index fa0e158a5..0dc12f407 100644
--- a/src/lib/ai/prompts/safety-contracts.ts
+++ b/src/lib/ai/prompts/safety-contracts.ts
@@ -187,11 +187,6 @@ export function loadSafetyContracts(locale: Locale): SafetyContractMatrix {
   return data;
 }
 
-/** Clear the in-process cache. Used in tests that swap matrices. */
-export function _resetSafetyContractsCacheForTests(): void {
-  cache = {};
-}
-
 /**
  * Return the locale-specific body of a ground rule. For EN the matrix
  * stores it under `.en`; for every other locale it lives under
@@ -213,20 +208,5 @@ export function getGroundRuleBody(
   return body;
 }
 
-/**
- * Iterate every (locale, ground-rule-key) pair. Used by the parity +
- * refusal-probe tests so they cover the full 14×6 = 84 grid without
- * hard-coding the locale list.
- */
-export function forEachLocaleAndRule(
-  fn: (locale: Locale, key: GroundRuleKey) => void,
-): void {
-  for (const locale of ALL_LOCALES) {
-    for (const key of GROUND_RULE_KEYS) {
-      fn(locale, key);
-    }
-  }
-}
-
 /** Ordered locale list — exported so tests can iterate identically. */
 export const SAFETY_CONTRACT_LOCALES = ALL_LOCALES;
diff --git a/src/lib/analytics/classifications.ts b/src/lib/analytics/classifications.ts
index ebdae36d3..9eba5b3df 100644
--- a/src/lib/analytics/classifications.ts
+++ b/src/lib/analytics/classifications.ts
@@ -305,13 +305,6 @@ export function getWeightRange(heightCm: number): { min: number; max: number } {
   };
 }
 
-/**
- * Normal resting pulse range (AHA).
- */
-export function getPulseRange(): { min: number; max: number } {
-  return { min: 60, max: 100 };
-}
-
 /**
  * Recommended nightly sleep duration for adults (AASM/SRS).
  */
diff --git a/src/lib/analytics/trends.ts b/src/lib/analytics/trends.ts
index e22127e0b..d8971b720 100644
--- a/src/lib/analytics/trends.ts
+++ b/src/lib/analytics/trends.ts
@@ -104,57 +104,6 @@ export function trendSlope(
   };
 }
 
-// ── Trend Line Points ────────────────────────────────────
-
-/**
- * Generate two data points representing the linear trend line endpoints.
- * Used by chart components to overlay a regression line.
- */
-export function trendLinePoints(
-  data: DataPoint[],
-  windowDays: number,
-): { start: DataPoint; end: DataPoint } | null {
-  if (data.length < 2) return null;
-
-  const sorted = [...data].sort((a, b) => a.date.getTime() - b.date.getTime());
-  const cutoff =
-    sorted[sorted.length - 1].date.getTime() - windowDays * 24 * 60 * 60 * 1000;
-  const window = sorted.filter((p) => p.date.getTime() >= cutoff);
-
-  if (window.length < 2) return null;
-
-  const startTime = window[0].date.getTime();
-  const points = window.map((p) => ({
-    x: (p.date.getTime() - startTime) / (24 * 60 * 60 * 1000),
-    y: p.value,
-  }));
-
-  const n = points.length;
-  const sumX = points.reduce((s, p) => s + p.x, 0);
-  const sumY = points.reduce((s, p) => s + p.y, 0);
-  const sumXY = points.reduce((s, p) => s + p.x * p.y, 0);
-  const sumXX = points.reduce((s, p) => s + p.x * p.x, 0);
-
-  const denominator = n * sumXX - sumX * sumX;
-  if (denominator === 0) return null;
-
-  const slope = (n * sumXY - sumX * sumY) / denominator;
-  const intercept = (sumY - slope * sumX) / n;
-
-  const endDays = points[points.length - 1].x;
-
-  return {
-    start: {
-      date: window[0].date,
-      value: Math.round(intercept * 100) / 100,
-    },
-    end: {
-      date: window[window.length - 1].date,
-      value: Math.round((intercept + slope * endDays) * 100) / 100,
-    },
-  };
-}
-
 // ── Anomaly Detection ────────────────────────────────────
 
 export interface Anomaly {
diff --git a/src/lib/charts/constants.ts b/src/lib/charts/constants.ts
index 74209c4ca..d6494a9c2 100644
--- a/src/lib/charts/constants.ts
+++ b/src/lib/charts/constants.ts
@@ -16,13 +16,6 @@
 /** Full-size trend-card body height (non-mini chart cards on the dashboard). */
 export const CHART_HEIGHT_PX = 240;
 
-/**
- * Compact / mini variant used by inline previews (rationale cards,
- * dashboard tile carve-outs). Smaller so the chart fits inside a host
- * card without doubling its vertical footprint.
- */
-export const CHART_MINI_HEIGHT_PX = 160;
-
 /**
  * Range-preset options for charts that expose a 7d / 30d / 90d / All
  * range selector. Each entry carries the i18n keys for the visible
diff --git a/src/lib/format.ts b/src/lib/format.ts
index 5a27a29e1..85e72959f 100644
--- a/src/lib/format.ts
+++ b/src/lib/format.ts
@@ -61,7 +61,3 @@ export function formatTime(date: Date | string): string {
   return formatters().time(date);
 }
 
-/** Locale-aware short weekday + date. */
-export function formatDateWithWeekday(date: Date | string): string {
-  return formatters().dateWithWeekday(date);
-}
diff --git a/src/lib/insights/general-status.ts b/src/lib/insights/general-status.ts
index b2073ad40..1c4ce1479 100644
--- a/src/lib/insights/general-status.ts
+++ b/src/lib/insights/general-status.ts
@@ -403,8 +403,3 @@ export async function generateGeneralStatusForUser(
   };
 }
 
-export function resolveGeneralStatusLocale(
-  locale: string | null | undefined,
-): SupportedLocale {
-  return normalizeLocale(locale);
-}
diff --git a/src/lib/insights/prompt.ts b/src/lib/insights/prompt.ts
index ddff3689f..18fa44368 100644
--- a/src/lib/insights/prompt.ts
+++ b/src/lib/insights/prompt.ts
@@ -40,77 +40,6 @@ export interface ComparisonSnapshot {
   }>;
 }
 
-const INSIGHTS_SYSTEM_PROMPT_DE = `Du bist ein Gesundheitsdaten-Insights-Assistent. Du analysierst aggregierte Gesundheitsdaten und gibst klare, datenbasierte Hinweise.
-
-WICHTIGE REGELN:
-- Erkläre immer, welche Datenpunkte zu deinen Schlussfolgerungen geführt haben.
-- Gib ein Konfidenzniveau an (niedrig/mittel/hoch) basierend auf der Datenmenge UND Datendichte.
-- Antworte auf Deutsch. Das Feld "confidence" muss exakt einer der englischen Enum-Schlüssel ("niedrig"|"mittel"|"hoch") sein — nicht übersetzen.
-
-DATENABDECKUNG UND MESSZEITRÄUME:
-- Jede Metrik enthält ein "coverage"-Objekt mit: count (Anzahl Messungen), spanDays (Zeitspanne in Tagen), avgDaysBetween (durchschnittlicher Abstand zwischen Messungen), oldestDaysAgo und newestDaysAgo.
-- Berücksichtige diese Informationen bei deiner Analyse:
-  * Weniger als 5 Messpunkte pro Metrik: Sage explizit, dass noch nicht genügend Daten für eine fundierte Aussage vorliegen.
-  * Große Lücken (avgDaysBetween > 7): Weise darauf hin, dass die Daten spärlich sind und Trends nur eingeschränkt belastbar sind.
-  * Daten über einen langen Zeitraum (spanDays > 60) aber wenig Messpunkte: Versuche trotzdem eine grobe Entwicklung abzuleiten, weise aber auf die eingeschränkte Aussagekraft hin.
-  * Wenn die neueste Messung länger als 7 Tage zurückliegt (newestDaysAgo > 7): Erwähne, dass die Daten nicht aktuell sind.
-- context.dataSpanDays zeigt den Gesamtzeitraum aller Messungen, context.oldestMeasurementDaysAgo und context.newestMeasurementDaysAgo den ältesten und neuesten Messpunkt.
-
-AUSGABEFORMAT (JSON):
-{
-  "changed": "Was hat sich verändert? (Bezug auf Zeiträume und Datenbasis)",
-  "stable": "Was ist stabil geblieben?",
-  "drivers": "Mögliche Zusammenhänge und Hypothesen (mit Vorsicht formuliert)",
-  "nextSteps": "Nächste kleine Schritte",
-  "confidence": "niedrig|mittel|hoch",
-  "limitations": "Einschränkungen dieser Analyse (inkl. Datenlücken und Messhäufigkeit)"
-}
-
-Antworte NUR mit validem JSON im obigen Format. Alle natürlichsprachigen Felder auf Deutsch.`;
-
-const INSIGHTS_SYSTEM_PROMPT_EN = `You are a health-data insights assistant. You analyse aggregated health data and provide clear, data-backed observations.
-
-KEY RULES:
-- Always explain which data points drove each conclusion.
-- Provide a confidence level (niedrig/mittel/hoch) based on data volume AND density.
-- Reply in English. The "confidence" field must contain exactly one of the stable enum keys ("niedrig"|"mittel"|"hoch") — do not translate.
-
-DATA COVERAGE AND MEASUREMENT WINDOWS:
-- Each metric carries a "coverage" object with: count (number of measurements), spanDays (timespan in days), avgDaysBetween (mean spacing between measurements), oldestDaysAgo and newestDaysAgo.
-- Factor these into the analysis:
-  * Fewer than 5 points per metric: state explicitly that there is not yet enough data for a reliable statement.
-  * Large gaps (avgDaysBetween > 7): note that the data is sparse and trends are only weakly supported.
-  * Long span (spanDays > 60) but few points: still try to derive a coarse direction, but flag the limited reliability.
-  * If the newest measurement is more than 7 days old (newestDaysAgo > 7): mention that the data is not current.
-- context.dataSpanDays shows the overall span of all measurements; context.oldestMeasurementDaysAgo and context.newestMeasurementDaysAgo show the oldest and newest points.
-
-OUTPUT FORMAT (JSON):
-{
-  "changed": "What changed? (Reference time spans and data basis.)",
-  "stable": "What stayed stable?",
-  "drivers": "Possible associations and hypotheses (worded cautiously).",
-  "nextSteps": "Next small steps.",
-  "confidence": "niedrig|mittel|hoch",
-  "limitations": "Limitations of this analysis (incl. data gaps and measurement frequency)."
-}
-
-Reply with VALID JSON ONLY in the format above. All natural-language fields in English.`;
-
-export function getInsightsSystemPrompt(locale: Locale): string {
-  return locale === "en"
-    ? INSIGHTS_SYSTEM_PROMPT_EN
-    : INSIGHTS_SYSTEM_PROMPT_DE;
-}
-
-export interface InsightsOutput {
-  changed: string;
-  stable: string;
-  drivers: string;
-  nextSteps: string;
-  confidence: "niedrig" | "mittel" | "hoch";
-  limitations: string;
-}
-
 export function buildUserPrompt(
   featuresJson: string,
   privacyMode: string,
diff --git a/src/lib/insights/sub-page-metric.ts b/src/lib/insights/sub-page-metric.ts
index b66fe7060..4472d7c60 100644
--- a/src/lib/insights/sub-page-metric.ts
+++ b/src/lib/insights/sub-page-metric.ts
@@ -46,6 +46,3 @@ export const SUB_PAGE_SLUGS = Object.keys(SUB_PAGE_METRIC) as SubPageSlug[];
  */
 export const INSIGHTS_OVERVIEW_PATH = "/insights" as const;
 
-export function isSubPageSlug(value: string): value is SubPageSlug {
-  return (SUB_PAGE_SLUGS as readonly string[]).includes(value);
-}
diff --git a/src/lib/jobs/worker-status.ts b/src/lib/jobs/worker-status.ts
index 412739fc7..104a48854 100644
--- a/src/lib/jobs/worker-status.ts
+++ b/src/lib/jobs/worker-status.ts
@@ -44,11 +44,6 @@ export function markWorkerStarted() {
   status.lastHeartbeat = new Date().toISOString();
 }
 
-export function recordHeartbeat() {
-  const status = getStatus();
-  status.lastHeartbeat = new Date().toISOString();
-}
-
 export function recordReminderCheck() {
   const status = getStatus();
   status.lastReminderCheck = new Date().toISOString();
diff --git a/src/lib/notifications/types.ts b/src/lib/notifications/types.ts
index 749a37d0e..241a6fac0 100644
--- a/src/lib/notifications/types.ts
+++ b/src/lib/notifications/types.ts
@@ -20,15 +20,6 @@ export const EVENT_TYPES = [
 ] as const;
 export type EventType = (typeof EVENT_TYPES)[number];
 
-export const EVENT_TYPE_LABELS: Record<EventType, string> = {
-  MEDICATION_REMINDER: "Medication reminder",
-  MEASUREMENT_ANOMALY: "Anomalous measurements",
-  COMPLIANCE_LOW: "Low compliance",
-  WITHINGS_SYNC_FAILED: "Withings sync failed",
-  SYSTEM_ALERT: "System alerts",
-  PERSONAL_RECORD: "Personal records",
-};
-
 /**
  * Per-event default policy when no `NotificationPreference` row
  * exists. The dispatcher reads this to decide whether to fire on a
diff --git a/src/lib/rate-limit.ts b/src/lib/rate-limit.ts
index ececfaa1d..e336099b0 100644
--- a/src/lib/rate-limit.ts
+++ b/src/lib/rate-limit.ts
@@ -51,16 +51,6 @@ export async function checkRateLimit(
   };
 }
 
-/**
- * Delete expired rate limit entries. Called periodically by pg-boss.
- */
-export async function cleanupExpiredRateLimits(): Promise<number> {
-  const result = await prisma.$executeRaw`
-    DELETE FROM rate_limits WHERE reset_at < NOW()
-  `;
-  return result;
-}
-
 /**
  * Rate limit response headers.
  */
diff --git a/src/lib/validations/measurement.ts b/src/lib/validations/measurement.ts
index 7f7359d8e..45d37dc0c 100644
--- a/src/lib/validations/measurement.ts
+++ b/src/lib/validations/measurement.ts
@@ -41,15 +41,6 @@ export const glucoseContextEnum = z.enum([
   "BEDTIME",
 ]);
 
-export const sleepStageEnum = z.enum([
-  "IN_BED",
-  "AWAKE",
-  "ASLEEP",
-  "REM",
-  "CORE",
-  "DEEP",
-]);
-
 export const measurementSourceEnum = z.enum([
   "MANUAL",
   "WITHINGS",