diff --git a/app/radio_sync.py b/app/radio_sync.py
index 7fd44c5..cd57de8 100644
--- a/app/radio_sync.py
+++ b/app/radio_sync.py
@@ -834,7 +834,6 @@ async def stop_periodic_advert():
         logger.info("Stopped periodic advertisement")
 
 
-
 # Prevents reboot-loop: once we've rebooted to fix clock skew this session,
 # don't do it again (the hardware RTC case can't be fixed by reboot).
 _clock_reboot_attempted: bool = False
diff --git a/app/repository/repeater_telemetry.py b/app/repository/repeater_telemetry.py
index 405b3c5..a3dba86 100644
--- a/app/repository/repeater_telemetry.py
+++ b/app/repository/repeater_telemetry.py
@@ -1,10 +1,17 @@
 import json
 import logging
+import time
 
 from app.database import db
 
 logger = logging.getLogger(__name__)
 
+# Maximum age for telemetry history entries (30 days)
+_MAX_AGE_SECONDS = 30 * 86400
+
+# Maximum entries to keep per repeater (sanity cap)
+_MAX_ENTRIES_PER_REPEATER = 1000
+
 
 class RepeaterTelemetryRepository:
     @staticmethod
@@ -13,7 +20,7 @@ class RepeaterTelemetryRepository:
         timestamp: int,
         data: dict,
     ) -> None:
-        """Insert a telemetry history row with the full status snapshot as JSON."""
+        """Insert a telemetry history row and prune stale entries."""
         await db.conn.execute(
             """
             INSERT INTO repeater_telemetry_history
@@ -22,6 +29,28 @@ class RepeaterTelemetryRepository:
             """,
             (public_key, timestamp, json.dumps(data)),
         )
+
+        # Prune entries older than 30 days
+        cutoff = int(time.time()) - _MAX_AGE_SECONDS
+        await db.conn.execute(
+            "DELETE FROM repeater_telemetry_history WHERE public_key = ? AND timestamp < ?",
+            (public_key, cutoff),
+        )
+
+        # Cap at _MAX_ENTRIES_PER_REPEATER (keep newest)
+        await db.conn.execute(
+            """
+            DELETE FROM repeater_telemetry_history
+            WHERE public_key = ? AND id NOT IN (
+                SELECT id FROM repeater_telemetry_history
+                WHERE public_key = ?
+                ORDER BY timestamp DESC
+                LIMIT ?
+            )
+            """,
+            (public_key, public_key, _MAX_ENTRIES_PER_REPEATER),
+        )
+
         await db.conn.commit()
 
     @staticmethod
diff --git a/app/routers/repeaters.py b/app/routers/repeaters.py
index 29328a2..e9ee9c9 100644
--- a/app/routers/repeaters.py
+++ b/app/routers/repeaters.py
@@ -1,9 +1,7 @@
 import logging
 import time
-from typing import TYPE_CHECKING
 
 from fastapi import APIRouter, HTTPException
-from meshcore import EventType
 
 from app.dependencies import require_connected
 from app.models import (
diff --git a/frontend/src/components/repeater/RepeaterTelemetryHistoryPane.tsx b/frontend/src/components/repeater/RepeaterTelemetryHistoryPane.tsx
index ff39f4a..caf7952 100644
--- a/frontend/src/components/repeater/RepeaterTelemetryHistoryPane.tsx
+++ b/frontend/src/components/repeater/RepeaterTelemetryHistoryPane.tsx
@@ -123,9 +123,7 @@ export function TelemetryHistoryPane({
                 tick={{ fontSize: 10, fill: 'hsl(var(--muted-foreground))' }}
                 tickLine={false}
                 axisLine={false}
-                tickFormatter={(v) =>
-                  metric === 'uptime_seconds' ? formatUptime(v) : `${v}`
-                }
+                tickFormatter={(v) => (metric === 'uptime_seconds' ? formatUptime(v) : `${v}`)}
               />
               <RechartsTooltip
                 {...TOOLTIP_STYLE}
@@ -139,7 +137,8 @@ export function TelemetryHistoryPane({
                 formatter={(value: any, name: any) => {
                   const numVal = typeof value === 'number' ? value : Number(value);
                   const display = metric === 'uptime_seconds' ? formatUptime(numVal) : `${value}`;
-                  const suffix = metric === 'uptime_seconds' ? '' : config.unit ? ` ${config.unit}` : '';
+                  const suffix =
+                    metric === 'uptime_seconds' ? '' : config.unit ? ` ${config.unit}` : '';
                   const label =
                     metric === 'packets'
                       ? name === 'packets_received'
diff --git a/frontend/src/test/setup.ts b/frontend/src/test/setup.ts
index 05656d6..339b76d 100644
--- a/frontend/src/test/setup.ts
+++ b/frontend/src/test/setup.ts
@@ -8,7 +8,7 @@ class ResizeObserver {
 
 globalThis.ResizeObserver = ResizeObserver;
 
-// uPlot calls matchMedia at import time for DPI detection
+// Several components call matchMedia at import time for responsive detection
 if (typeof globalThis.matchMedia === 'undefined') {
   Object.defineProperty(globalThis, 'matchMedia', {
     value: (query: string) => ({
diff --git a/frontend/src/types.ts b/frontend/src/types.ts
index 523c156..26d77c6 100644
--- a/frontend/src/types.ts
+++ b/frontend/src/types.ts
@@ -473,7 +473,7 @@ export interface PaneState {
 
 export interface TelemetryHistoryEntry {
   timestamp: number;
-  data: RepeaterStatusResponse;
+  data: Record<string, number>;
 }
 
 export interface TraceResponse {
diff --git a/tests/test_repeater_telemetry.py b/tests/test_repeater_telemetry.py
index 760566e..46c3ecc 100644
--- a/tests/test_repeater_telemetry.py
+++ b/tests/test_repeater_telemetry.py
@@ -1,6 +1,5 @@
 """Tests for repeater telemetry history: repository CRUD and embedded status response."""
 
-import json
 import time
 
 import pytest