diff --git a/app/live_layers.py b/app/live_layers.py
index 3e214c6..c2ea170 100644
--- a/app/live_layers.py
+++ b/app/live_layers.py
@@ -49,7 +49,8 @@ CONUS = (-125.0, 24.0, -66.0, 50.0)
 MAX_RADIUS_NM = 150
 DEFAULT_LIMIT = 2000
 
-_HTTP_TIMEOUT = 25.0
+_HTTP_TIMEOUT = httpx.Timeout(8.0, connect=3.0)
+_http: httpx.AsyncClient | None = None
 _COMPASS = {
     "N": 0, "NE": 45, "E": 90, "SE": 135,
     "S": 180, "SW": 225, "W": 270, "NW": 315,
@@ -58,7 +59,9 @@ _COMPASS = {
 }
 
 _cache: dict[str, tuple[float, Any]] = {}
-_cache_lock = asyncio.Lock()
+_key_locks: dict[str, asyncio.Lock] = {}
+_key_locks_guard = asyncio.Lock()
+_QUANT = 0.25  # degrees — pan jitter inside a cell reuses the TTL entry
 
 # Last-known AIS positions (MMSI -> marker). Filled by ais_stream worker.
 vessel_last_known: dict[str, dict] = {}
@@ -116,6 +119,33 @@ def parse_bbox(bbox: str) -> tuple[float, float, float, float]:
     return minlon, minlat, maxlon, maxlat
 
 
+def quantize_bbox(
+    minlon: float, minlat: float, maxlon: float, maxlat: float,
+    step: float = _QUANT,
+) -> tuple[float, float, float, float]:
+    """Snap a viewport to a coarse cell so nearby pans share a cache key.
+
+    The returned envelope is expanded to cover the original box.
+    """
+    def q_down(v: float, lo: float, hi: float) -> float:
+        v = max(lo, min(hi, v))
+        return math.floor(v / step) * step
+
+    return (
+        round(q_down(minlon, -180.0, 180.0), 4),
+        round(q_down(minlat, -90.0, 90.0), 4),
+        round(q_down(maxlon, -180.0, 180.0) + step, 4),
+        round(q_down(maxlat, -90.0, 90.0) + step, 4),
+    )
+
+
+def bbox_cell_key(bbox: str | None) -> str:
+    """Stable cache-key fragment for a viewport (or 'all')."""
+    if not bbox:
+        return "all"
+    return ",".join(f"{v:.4f}" for v in quantize_bbox(*parse_bbox(bbox)))
+
+
 def bbox_center_radius_nm(
     minlon: float, minlat: float, maxlon: float, maxlat: float,
 ) -> tuple[float, float, int]:
@@ -177,6 +207,78 @@ def filter_points_bbox(
     return out
 
 
+_ALERT_KEEP = ("event", "severity", "headline", "areaDesc", "wfo", "source")
+
+
+def slim_alert_properties(props: dict | None) -> dict:
+    """Keep only the fields the map popup reads."""
+    src = props or {}
+    return {k: src.get(k) for k in _ALERT_KEEP}
+
+
+def _walk_coords(coords: Any, acc: list[float]) -> None:
+    if not coords:
+        return
+    first = coords[0]
+    if isinstance(first, (int, float)):
+        lon, lat = float(coords[0]), float(coords[1])
+        acc[0] = min(acc[0], lon)
+        acc[1] = min(acc[1], lat)
+        acc[2] = max(acc[2], lon)
+        acc[3] = max(acc[3], lat)
+        return
+    for child in coords:
+        _walk_coords(child, acc)
+
+
+def _geom_envelope(geom: dict | None) -> tuple[float, float, float, float] | None:
+    if not geom or not isinstance(geom, dict):
+        return None
+    if geom.get("type") == "GeometryCollection":
+        env: list[float] | None = None
+        for g in geom.get("geometries") or []:
+            e = _geom_envelope(g)
+            if e is None:
+                continue
+            if env is None:
+                env = list(e)
+            else:
+                env[0] = min(env[0], e[0])
+                env[1] = min(env[1], e[1])
+                env[2] = max(env[2], e[2])
+                env[3] = max(env[3], e[3])
+        return tuple(env) if env else None  # type: ignore[return-value]
+    coords = geom.get("coordinates")
+    if coords is None:
+        return None
+    acc = [180.0, 90.0, -180.0, -90.0]
+    try:
+        _walk_coords(coords, acc)
+    except (TypeError, ValueError, IndexError):
+        return None
+    if acc[0] > acc[2]:
+        return None
+    return acc[0], acc[1], acc[2], acc[3]
+
+
+def clip_fc_to_bbox(
+    fc: dict | None,
+    minlon: float, minlat: float, maxlon: float, maxlat: float,
+) -> dict:
+    """Drop features whose geometry envelope misses the viewport. No shapely."""
+    box = (minlon, minlat, maxlon, maxlat)
+    out = []
+    for feat in (fc or {}).get("features") or []:
+        if not isinstance(feat, dict):
+            continue
+        env = _geom_envelope(feat.get("geometry"))
+        if env is None:
+            continue
+        if env[0] <= box[2] and env[2] >= box[0] and env[1] <= box[3] and env[3] >= box[1]:
+            out.append(feat)
+    return {"type": "FeatureCollection", "features": out}
+
+
 def _f(value: object) -> float | None:
     if value is None or value == "":
         return None
@@ -404,12 +506,22 @@ def _headers() -> dict[str, str]:
     return {"User-Agent": OSINT_USER_AGENT, "Accept": "application/json"}
 
 
+async def _lock_for(key: str) -> asyncio.Lock:
+    async with _key_locks_guard:
+        lock = _key_locks.get(key)
+        if lock is None:
+            lock = asyncio.Lock()
+            _key_locks[key] = lock
+        return lock
+
+
 async def _ttl_get(key: str, ttl: float, factory: Callable[[], Awaitable[Any]]) -> Any:
     now = time.monotonic()
     hit = _cache.get(key)
     if hit and now - hit[0] < ttl:
         return hit[1]
-    async with _cache_lock:
+    lock = await _lock_for(key)
+    async with lock:
         hit = _cache.get(key)
         if hit and time.monotonic() - hit[0] < ttl:
             return hit[1]
@@ -418,17 +530,42 @@ async def _ttl_get(key: str, ttl: float, factory: Callable[[], Awaitable[Any]])
         return value
 
 
+async def init_http() -> None:
+    """Shared outbound client — one TLS pool for all overlay upstreams."""
+    global _http
+    if _http is None:
+        _http = httpx.AsyncClient(
+            timeout=_HTTP_TIMEOUT,
+            follow_redirects=True,
+            headers=_headers(),
+            limits=httpx.Limits(max_connections=20, max_keepalive_connections=10),
+        )
+
+
+async def close_http() -> None:
+    global _http
+    if _http is not None:
+        await _http.aclose()
+        _http = None
+
+
 async def _get_json(url: str, params: dict | None = None) -> Any:
-    async with httpx.AsyncClient(timeout=_HTTP_TIMEOUT, follow_redirects=True,
-                                 headers=_headers()) as client:
-        resp = await client.get(url, params=params)
-        resp.raise_for_status()
-        return resp.json()
+    if _http is None:
+        async with httpx.AsyncClient(
+            timeout=_HTTP_TIMEOUT, follow_redirects=True, headers=_headers(),
+        ) as client:
+            resp = await client.get(url, params=params)
+            resp.raise_for_status()
+            return resp.json()
+    resp = await _http.get(url, params=params)
+    resp.raise_for_status()
+    return resp.json()
 
 
 async def fetch_aircraft(bbox: str, limit: int = DEFAULT_LIMIT) -> list[dict]:
     minlon, minlat, maxlon, maxlat = parse_bbox(bbox)
-    lat, lon, radius = bbox_center_radius_nm(minlon, minlat, maxlon, maxlat)
+    qminlon, qminlat, qmaxlon, qmaxlat = quantize_bbox(minlon, minlat, maxlon, maxlat)
+    lat, lon, radius = bbox_center_radius_nm(qminlon, qminlat, qmaxlon, qmaxlat)
     cache_key = f"adsb:{lat:.2f}:{lon:.2f}:{radius}"
 
     async def _load():
@@ -485,15 +622,17 @@ async def upsert_vessel(marker: dict) -> None:
         }
 
 
-def _wfigs_params(bbox: str | None) -> dict:
+def _wfigs_params(bbox: str | None, *, offset_m: float = 250.0) -> dict:
     params = {
         "where": "1=1",
         "outSR": "4326",
         "f": "geojson",
-        "resultRecordCount": 2000,
+        "resultRecordCount": 500,
+        "maxAllowableOffset": offset_m / 111_320.0,  # metres → degrees
+        "geometryPrecision": 5,
     }
     if bbox:
-        minlon, minlat, maxlon, maxlat = parse_bbox(bbox)
+        minlon, minlat, maxlon, maxlat = quantize_bbox(*parse_bbox(bbox))
         params["geometry"] = f"{minlon},{minlat},{maxlon},{maxlat}"
         params["geometryType"] = "esriGeometryEnvelope"
         params["inSR"] = "4326"
@@ -511,7 +650,7 @@ async def fetch_fire_incidents(bbox: str | None, limit: int = DEFAULT_LIMIT) ->
     async def _load():
         return transform_wfigs_incidents(await _get_json(WFIGS_INCIDENTS, params))
 
-    rows = await _ttl_get(f"wfigs:inc:{bbox or 'all'}", 600.0, _load)
+    rows = await _ttl_get(f"wfigs:inc:{bbox_cell_key(bbox)}", 600.0, _load)
     return rows[:limit]
 
 
@@ -525,7 +664,7 @@ async def fetch_fire_perimeters(bbox: str | None) -> dict:
     async def _load():
         return await _get_json(WFIGS_PERIMETERS, params)
 
-    fc = await _ttl_get(f"wfigs:per:{bbox or 'all'}", 600.0, _load)
+    fc = await _ttl_get(f"wfigs:per:{bbox_cell_key(bbox)}", 600.0, _load)
     if not isinstance(fc, dict):
         return {"type": "FeatureCollection", "features": []}
     return fc
@@ -534,44 +673,50 @@ async def fetch_fire_perimeters(bbox: str | None) -> dict:
 async def fetch_weather_alerts(area: str | None, bbox: str | None) -> dict:
     """Cached NWS active alerts + IEM storm-based warning polygons."""
 
+    async def _load_iem():
+        try:
+            data = await _get_json(IEM_SBW)
+        except Exception:
+            return {"type": "FeatureCollection", "features": []}
+        return data if isinstance(data, dict) else {"type": "FeatureCollection", "features": []}
+
     async def _load():
         nws_params: dict[str, str] = {"status": "actual"}
+        clip_box = None
         if area:
             nws_params["area"] = area.upper()
         elif bbox:
-            minlon, minlat, maxlon, maxlat = parse_bbox(bbox)
-            nws_params["bbox"] = f"{minlon},{minlat},{maxlon},{maxlat}"
+            clip_box = quantize_bbox(*parse_bbox(bbox))
+            nws_params["bbox"] = f"{clip_box[0]},{clip_box[1]},{clip_box[2]},{clip_box[3]}"
         nws_fc: dict = {"features": []}
-        sbw_fc: dict = {"features": []}
         try:
             nws_fc = await _get_json(NWS_ALERTS, nws_params)
         except Exception:
             nws_fc = {"features": []}
-        try:
-            sbw_fc = await _get_json(IEM_SBW)
-        except Exception:
-            sbw_fc = {"features": []}
+        sbw_fc = await _ttl_get("iem:sbw", 45.0, _load_iem)
         features = []
         for feat in nws_fc.get("features") or []:
-            props = feat.get("properties") or {}
+            if not isinstance(feat, dict):
+                continue
+            props = dict(feat.get("properties") or {})
             props["source"] = "nws"
-            feat["properties"] = props
-            features.append(feat)
-        for feat in sbw_fc.get("features") or []:
-            props = feat.get("properties") or {}
+            features.append({**feat, "properties": slim_alert_properties(props)})
+        for feat in (sbw_fc or {}).get("features") or []:
+            if not isinstance(feat, dict):
+                continue
+            props = dict(feat.get("properties") or {})
             props["source"] = "iem-sbw"
-            # IEM uses `ps` (phenomenon) / `wfo`; map a display event.
             if "event" not in props:
                 props["event"] = props.get("ps") or "Storm-based warning"
-            feat["properties"] = props
-            if bbox:
-                # Cheap reject: skip if no geometry; keep otherwise (polygons).
-                if not feat.get("geometry"):
-                    continue
-            features.append(feat)
-        return {"type": "FeatureCollection", "features": features}
+            features.append({**feat, "properties": slim_alert_properties(props)})
+        merged = {"type": "FeatureCollection", "features": features}
+        if clip_box:
+            merged = clip_fc_to_bbox(merged, *clip_box)
+        elif bbox:
+            merged = clip_fc_to_bbox(merged, *parse_bbox(bbox))
+        return merged
 
-    key = f"alerts:{area or ''}:{bbox or ''}"
+    key = f"alerts:{area or ''}:{bbox_cell_key(bbox) if bbox else ''}"
     return await _ttl_get(key, 30.0, _load)
 
 
diff --git a/app/main.py b/app/main.py
index 3b4defe..7da2f84 100644
--- a/app/main.py
+++ b/app/main.py
@@ -14,6 +14,7 @@ from __future__ import annotations
 import asyncio
 import json
 import logging
+from contextlib import asynccontextmanager
 from datetime import datetime, timedelta, timezone
 from decimal import Decimal
 from pathlib import Path
@@ -21,7 +22,8 @@ from uuid import UUID
 
 import structlog
 from fastapi import FastAPI, HTTPException, Query
-from fastapi.responses import FileResponse, HTMLResponse
+from fastapi.middleware.gzip import GZipMiddleware
+from fastapi.responses import FileResponse, HTMLResponse, JSONResponse
 from fastapi.staticfiles import StaticFiles
 from sqlalchemy import and_, func, or_, select, text
 from sqlalchemy.ext.asyncio import AsyncSession
@@ -53,11 +55,30 @@ from live_layers import (
 logging.basicConfig(level=logging.INFO)
 logger = structlog.get_logger("osint.dashboard")
 
+
+@asynccontextmanager
+async def _lifespan(app: FastAPI):
+    await init_extensions()
+    from live_layers import close_http, init_http
+    await init_http()
+    from config import AISSTREAM_IN_APP
+    ais_task = None
+    if AISSTREAM_IN_APP:
+        from ais_stream import run_ais_worker
+        ais_task = asyncio.create_task(run_ais_worker())
+    yield
+    if ais_task is not None:
+        ais_task.cancel()
+    await close_http()
+
+
 app = FastAPI(
     title="OSINT Dashboard",
     description="Real-time geospatial OSINT intelligence dashboard",
     version="0.1.0",
+    lifespan=_lifespan,
 )
+app.add_middleware(GZipMiddleware, minimum_size=1024)
 
 STATIC_DIR = Path(__file__).parent / "static"
 
@@ -69,17 +90,17 @@ def event_to_out(row: dict) -> EventOut:
     return EventOut(
         id=row["id"],
         source_type=row["source_type"],
-        source_id=row["source_id"],
-        title=row["title"],
-        body=row["body"],
-        url=row["url"],
-        sentiment_score=row["sentiment_score"],
-        sentiment_label=row["sentiment_label"],
-        location_lat=row["location_lat"],
-        location_lon=row["location_lon"],
-        location_name=row["location_name"],
-        entities=row["entities"],
-        tags=row["tags"],
+        source_id=row.get("source_id"),
+        title=row.get("title"),
+        body=row.get("body"),
+        url=row.get("url"),
+        sentiment_score=row.get("sentiment_score"),
+        sentiment_label=row.get("sentiment_label"),
+        location_lat=row.get("location_lat"),
+        location_lon=row.get("location_lon"),
+        location_name=row.get("location_name"),
+        entities=row.get("entities"),
+        tags=row.get("tags"),
         ingested_at=row["ingested_at"],
         source_timestamp=row["source_timestamp"],
     )
@@ -131,20 +152,11 @@ async def health():
     return {"status": "ok", "db_time": db_time.isoformat() if db_time else None}
 
 
-# ── Startup ───────────────────────────────────────────────────────────────
-
-@app.on_event("startup")
-async def startup():
-    """Initialize PostGIS/TimescaleDB extensions on first connection.
-
-    Schema migrations are applied by the container entrypoint (alembic upgrade
-    head) before uvicorn starts, so they don't run nested inside the event loop.
-    """
-    await init_extensions()
-    from config import AISSTREAM_IN_APP
-    if AISSTREAM_IN_APP:
-        from ais_stream import run_ais_worker
-        asyncio.create_task(run_ais_worker())
+def overlay_json(data, max_age: int) -> JSONResponse:
+    """JSON overlay payload with a short browser/proxy TTL."""
+    resp = JSONResponse(content=data)
+    resp.headers["Cache-Control"] = f"public, max-age={max_age}"
+    return resp
 
 
 # ── Feed Sources ──────────────────────────────────────────────────────────
@@ -218,7 +230,15 @@ async def list_events(
 ):
     """List recent ingested events."""
     async with async_session() as session:
-        stmt = select(events).order_by(events.c.ingested_at.desc())
+        if has_coords:
+            stmt = select(
+                events.c.id, events.c.source_type, events.c.source_id,
+                events.c.title, events.c.url,
+                events.c.location_lat, events.c.location_lon, events.c.location_name,
+                events.c.ingested_at, events.c.source_timestamp,
+            ).order_by(events.c.ingested_at.desc())
+        else:
+            stmt = select(events).order_by(events.c.ingested_at.desc())
         if source_type:
             stmt = stmt.where(events.c.source_type == source_type.value)
         if since:
@@ -272,7 +292,29 @@ async def create_event(payload: EventCreate):
 
 # ── Active Fires / Hotspots (NASA FIRMS) ─────────────────────────────────
 
-@app.get("/api/fires", response_model=list[FireOut])
+def fire_heat_row(r) -> dict:
+    """Minimal FIRMS point for the heatmap overlay."""
+    return {
+        "lat": r["latitude"],
+        "lon": r["longitude"],
+        "i": r["brightness"],
+        "c": r["confidence"],
+    }
+
+
+def camera_map_row(r) -> dict:
+    """Minimal camera pin — URLs stay off the list payload."""
+    return {
+        "id": str(r["id"]),
+        "lat": r["location_lat"],
+        "lon": r["location_lon"],
+        "device_type": r["device_type"],
+        "discovery_source": r["discovery_source"],
+        "location_name": r["location_name"],
+    }
+
+
+@app.get("/api/fires", response_model=None)
 async def list_fires(
     bbox: str | None = Query(
         None,
@@ -286,12 +328,16 @@ async def list_fires(
                     "(ISO 8601, e.g. '2026-08-24T12:00:00Z').",
     ),
     limit: int = Query(2000, ge=1, le=10000),
+    format: str = Query("full", description="'full' FireOut rows or 'heat' {lat,lon,i,c}"),
 ):
     """List stored FIRMS active fire/hotspot detections as JSON.
 
     This is the data contract for the map's fire heatmap overlay: the frontend
-    calls `GET /api/fires?bbox=...&since=...` and renders the returned points.
+    calls `GET /api/fires?bbox=...&since=...&format=heat` and renders the points.
     """
+    fmt = (format or "full").lower()
+    if fmt not in ("full", "heat"):
+        raise HTTPException(422, "format must be 'full' or 'heat'")
     async with async_session() as session:
         stmt = select(fires).order_by(fires.c.acq_time.desc())
         if since:
@@ -316,6 +362,8 @@ async def list_fires(
             )
         stmt = stmt.limit(limit)
         rows = (await session.execute(stmt)).mappings().all()
+    if fmt == "heat":
+        return [fire_heat_row(r) for r in rows]
     return [
         FireOut(
             latitude=r["latitude"], longitude=r["longitude"],
@@ -798,7 +846,11 @@ async def list_cameras(
             stmt = stmt.where(cam_table.c.discovery_source == source)
         rows = (await session.execute(stmt.limit(limit))).mappings().all()
 
-    return [{
+    return [camera_map_row(r) for r in rows]
+
+
+def camera_detail_row(r) -> dict:
+    return {
         "id": str(r["id"]),
         "source_url": r["source_url"],
         "snapshot_url": r["snapshot_url"],
@@ -808,9 +860,23 @@ async def list_cameras(
         "location_name": r["location_name"],
         "vendor": r["vendor"],
         "device_type": r["device_type"],
-        "first_seen": r["first_seen"].isoformat(),
-        "last_seen": r["last_seen"].isoformat(),
-    } for r in rows]
+        "first_seen": r["first_seen"].isoformat() if r["first_seen"] else None,
+        "last_seen": r["last_seen"].isoformat() if r["last_seen"] else None,
+    }
+
+
+@app.get("/api/cameras/{camera_id}")
+async def get_camera(camera_id: UUID):
+    """Full camera row for a map popup. List endpoint stays slim."""
+    from camera_models import cameras as cam_table
+
+    async with async_session() as session:
+        row = (await session.execute(
+            select(cam_table).where(cam_table.c.id == camera_id)
+        )).mappings().one_or_none()
+    if not row:
+        raise HTTPException(404, "Camera not found")
+    return camera_detail_row(row)
 
 
 @app.get("/api/cameras/{camera_id}/snapshot")
@@ -959,6 +1025,10 @@ async def list_news(
     ),
     limit: int = Query(50, ge=1, le=500),
     offset: int = Query(0, ge=0),
+    include_content: bool = Query(
+        False,
+        description="Include full article body. Default false — ticker/list only need title/url.",
+    ),
 ):
     """Most recent scraped news articles (newest first)."""
     async with async_session() as session:
@@ -974,7 +1044,7 @@ async def list_news(
     return [
         NewsArticleOut(
             id=r["id"], title=r["title"], url=r["url"],
-            content=r["content"], domain=r["domain"],
+            content=r["content"] if include_content else None, domain=r["domain"],
             timestamp=r["timestamp"],
         )
         for r in rows
@@ -1056,7 +1126,7 @@ def _upstream_or_502(exc: Exception, name: str):
 async def map_radar():
     """RainViewer frame list + IEM NEXRAD tile template. Browser fetches tiles."""
     try:
-        return await fetch_radar_meta()
+        return overlay_json(await fetch_radar_meta(), 60)
     except Exception as exc:
         _upstream_or_502(exc, "radar")
 
@@ -1069,7 +1139,7 @@ async def list_aircraft(
     """Viewport ADS-B last-known (ADSB.lol). Requires bbox; radius clamped ≤ 150 nm."""
     _parse_bbox_query(bbox)
     try:
-        return await fetch_aircraft(bbox, limit)
+        return overlay_json(await fetch_aircraft(bbox, limit), 5)
     except ValueError as exc:
         raise HTTPException(422, str(exc)) from exc
     except Exception as exc:
@@ -1085,7 +1155,7 @@ async def list_trains(
     if bbox:
         _parse_bbox_query(bbox)
     try:
-        return await fetch_trains(bbox, limit)
+        return overlay_json(await fetch_trains(bbox, limit), 20)
     except ValueError as exc:
         raise HTTPException(422, str(exc)) from exc
     except Exception as exc:
@@ -1101,7 +1171,7 @@ async def list_vessels(
     if bbox:
         _parse_bbox_query(bbox)
     try:
-        return await fetch_vessels(bbox, limit)
+        return overlay_json(await fetch_vessels(bbox, limit), 5)
     except ValueError as exc:
         raise HTTPException(422, str(exc)) from exc
 
@@ -1115,7 +1185,7 @@ async def list_fire_incidents(
     if bbox:
         _parse_bbox_query(bbox)
     try:
-        return await fetch_fire_incidents(bbox, limit)
+        return overlay_json(await fetch_fire_incidents(bbox, limit), 30)
     except Exception as exc:
         _upstream_or_502(exc, "fire-incidents")
 
@@ -1126,7 +1196,7 @@ async def list_fire_perimeters(bbox: str | None = Query(None)):
     if bbox:
         _parse_bbox_query(bbox)
     try:
-        return await fetch_fire_perimeters(bbox)
+        return overlay_json(await fetch_fire_perimeters(bbox), 30)
     except Exception as exc:
         _upstream_or_502(exc, "fire-perimeters")
 
@@ -1144,7 +1214,7 @@ async def list_weather_alerts(
     if bbox:
         _parse_bbox_query(bbox)
     try:
-        return await fetch_weather_alerts(area, bbox)
+        return overlay_json(await fetch_weather_alerts(area, bbox), 30)
     except Exception as exc:
         _upstream_or_502(exc, "weather-alerts")
 
@@ -1153,7 +1223,7 @@ async def list_weather_alerts(
 async def list_storms():
     """NHC active tropical cyclones."""
     try:
-        return await fetch_storms()
+        return overlay_json(await fetch_storms(), 20)
     except Exception as exc:
         _upstream_or_502(exc, "storms")
 
diff --git a/app/static/index.html b/app/static/index.html
index 98c44a0..4012750 100644
--- a/app/static/index.html
+++ b/app/static/index.html
@@ -1026,10 +1026,22 @@
 <script src="/static/vendor/leaflet/leaflet.js"></script>
 <script src="/static/vendor/leaflet/leaflet.markercluster.js"></script>
 <script src="/static/vendor/leaflet/leaflet.heat.js"></script>
-<script src="/static/vendor/hls/hls.min.js"></script>
 <script>
 const API = '';
 
+function loadHls() {
+    if (window.Hls) return Promise.resolve();
+    if (window._hlsLoading) return window._hlsLoading;
+    window._hlsLoading = new Promise((res, rej) => {
+        const s = document.createElement('script');
+        s.src = '/static/vendor/hls/hls.min.js';
+        s.onload = res;
+        s.onerror = rej;
+        document.head.appendChild(s);
+    });
+    return window._hlsLoading;
+}
+
 /* ═══════════════ BOOT SPLASH ═══════════════ */
 (function () {
     const boot = document.getElementById('boot');
@@ -1136,7 +1148,8 @@ function showView(name) {
         }
     }
     if (name === 'news') loadNews(false);
-    if (name === 'settings') renderSysInfo();
+    if (name === 'events') { loadSummary(); loadEvents(); }
+    if (name === 'settings') { loadSummary(); renderSysInfo(); }
     window.scrollTo(0, 0);
 }
 
@@ -1637,6 +1650,16 @@ let vesselsGroup = null, vesselsOn = false;
 let stormsGroup = null, stormsOn = true;
 let overlayReq = {ac:0, trains:0, vessels:0, alerts:0, perim:0, incidents:0, storms:0};
 let moveDebounce = null;
+let overlayAbort = null;
+let lastCell = '';
+function bboxCell() {
+    if (!map) return '';
+    return currentBBox().split(',').map(n => Number(n).toFixed(2)).join(',') + '@' + map.getZoom();
+}
+function overlayFetch(url) {
+    return fetch(url, overlayAbort ? { signal: overlayAbort.signal } : {});
+}
+function isAbort(e) { return e && e.name === 'AbortError'; }
 const pointCanvas = () => L.canvas({ padding: 0.5 });
 
 async function initMap() {
@@ -1651,7 +1674,10 @@ async function initMap() {
         const sel = document.getElementById('map-layer');
         sel.innerHTML = mapLayers.map(l =>
             `<option value="${l.id}">${l.title}</option>`).join('');
-        const preferred = mapLayers.find(l => l.has_time) || mapLayers[0];
+        const preferred =
+            mapLayers.find(l => l.id === 'BlueMarble_ShadedRelief_Bathymetry')
+            || mapLayers.find(l => !l.has_time)
+            || mapLayers[0];
         if (preferred) sel.value = preferred.id;
         map = L.map('map', {
             center: [25, 10], zoom: 2,
@@ -1676,20 +1702,24 @@ async function initMap() {
                 img.alt = 'camera preview';
                 v.replaceWith(img);
             };
-            if (window.Hls && Hls.isSupported()) {
-                activeHls = new Hls({ enableWorker: true, lowLatencyMode: true });
-                activeHls.loadSource(v.dataset.hls);
-                activeHls.attachMedia(v);
-                v.play && v.play().catch(() => {});
-                activeHls.on(Hls.Events.ERROR, (_, data) => {
-                    if (data && data.fatal) fallback();
-                });
-            } else if (v.canPlayType && v.canPlayType('application/vnd.apple.mpegurl')) {
-                v.src = v.dataset.hls;
-                v.addEventListener('error', fallback, { once: true });
-            } else {
-                fallback();
-            }
+            const startHls = () => {
+                if (window.Hls && Hls.isSupported()) {
+                    activeHls = new Hls({ enableWorker: true, lowLatencyMode: true });
+                    activeHls.loadSource(v.dataset.hls);
+                    activeHls.attachMedia(v);
+                    v.play && v.play().catch(() => {});
+                    activeHls.on(Hls.Events.ERROR, (_, data) => {
+                        if (data && data.fatal) fallback();
+                    });
+                } else if (v.canPlayType && v.canPlayType('application/vnd.apple.mpegurl')) {
+                    v.src = v.dataset.hls;
+                    v.addEventListener('error', fallback, { once: true });
+                } else {
+                    fallback();
+                }
+            };
+            if (window.Hls) startHls();
+            else loadHls().then(startHls).catch(fallback);
         });
         map.on('popupclose', () => {
             if (activeHls) { try { activeHls.destroy(); } catch (_) {} activeHls = null; }
@@ -1713,13 +1743,19 @@ async function initMap() {
             if (camPopupOpen) return; // only the popup's own autopan now
             if (moveDebounce) clearTimeout(moveDebounce);
             moveDebounce = setTimeout(() => {
+                const cell = bboxCell();
+                if (cell === lastCell) return;
+                lastCell = cell;
+                if (overlayAbort) overlayAbort.abort();
+                overlayAbort = new AbortController();
                 if (firesOn) loadFires();
                 if (camsOn) loadCams();
                 if (blipsOn) loadBlips();
                 refreshLiveOverlays();
             }, 300);
         });
-        await mapLayerChanged();
+        // Static Blue Marble has no time-domain fetch — don't block overlays on GIBS.
+        mapLayerChanged();
         // Overlays default ON (checkboxes in the layer panel + saved settings)
         applyMapSettings(readMapPrefs(), false);
         firesOn = document.getElementById('lp-fires-on').checked;
@@ -1900,10 +1936,12 @@ function setBaseOpacity(v) {
 
 /* ── FIRMS fire heatmap ── */
 function firesIntensity(f) {
+    const confidence = f.confidence || f.c;
+    const brightness = f.brightness != null ? f.brightness : f.i;
     if (firesColor === 'confidence') {
-        return f.confidence === 'h' ? 1.0 : f.confidence === 'l' ? 0.35 : 0.6;
+        return confidence === 'h' ? 1.0 : confidence === 'l' ? 0.35 : 0.6;
     }
-    const b = f.brightness || 300;
+    const b = brightness || 300;
     return Math.max(0.05, Math.min(1, (b - 290) / 110));
 }
 function firesGradient() {
@@ -1951,14 +1989,14 @@ async function loadFires() {
     if (!map) return;
     const req = ++fireReq;
     try {
-        let url = `${API}/api/fires?bbox=${currentBBox()}&limit=2000`;
+        let url = `${API}/api/fires?bbox=${currentBBox()}&limit=2000&format=heat`;
         const since = sinceToISO(firesSince);
         if (since) url += `&since=${encodeURIComponent(since)}`;
-        const r = await fetch(url);
+        const r = await overlayFetch(url);
         const fires = await r.json();
         if (req !== fireReq) return; // superseded by a newer pan/zoom
         if (firesHeat) map.removeLayer(firesHeat);
-        const pts = fires.map(f => [f.latitude, f.longitude, firesIntensity(f)]);
+        const pts = fires.map(f => [f.lat ?? f.latitude, f.lon ?? f.longitude, firesIntensity(f)]);
         firesHeat = L.heatLayer(pts, {
             radius: 22, blur: 20, maxZoom: 9, max: 1.0, minOpacity: 0.2,
             gradient: firesGradient(),
@@ -1971,6 +2009,7 @@ async function loadFires() {
             `${fires.length.toLocaleString()} fire hotspots in view` +
             (since ? ` · since ${since.slice(0,16).replace('T',' ')}Z` : '');
     } catch(e) {
+        if (isAbort(e)) return;
         document.getElementById('map-hint').textContent = `Fires load failed: ${e.message || e}`;
         console.error('Fires load failed', e);
     }
@@ -2036,9 +2075,16 @@ function camThumb(c) {
 }
 async function loadCams() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        camsGroup = dropLayer(camsGroup);
+        markZoom('lp-cams-count');
+        hudCamsCount = null;
+        syncHud();
+        return;
+    }
     const req = ++camReq;
     try {
-        const r = await fetch(`${API}/api/cameras?bbox=${currentBBox()}&limit=5000`);
+        const r = await overlayFetch(`${API}/api/cameras?bbox=${currentBBox()}&limit=2000`);
         const cams = await r.json();
         if (req !== camReq) return; // superseded by a newer pan/zoom
         if (camsGroup) map.removeLayer(camsGroup);
@@ -2062,7 +2108,7 @@ async function loadCams() {
                 iconSize: [12, 12], iconAnchor: [6, 6],
             });
             camsGroup.addLayer(L.marker([c.lat, c.lon], { icon })
-                .bindPopup(`<div class="cam-pop">` +
+                .bindPopup(() => `<div class="cam-pop">` +
                     `<b>${esc(c.location_name || 'Open camera')}</b>` +
                     `${c.id ? camThumb(c) : '<div class="thumb placeholder">no snapshot</div>'}` +
                     `<table>` +
@@ -2083,6 +2129,7 @@ async function loadCams() {
         document.getElementById('map-hint').textContent =
             `${cams.length.toLocaleString()} open cameras in view`;
     } catch(e) {
+        if (isAbort(e)) return;
         document.getElementById('map-hint').textContent = `Cameras load failed: ${e.message || e}`;
         console.error('Cameras load failed', e);
     }
@@ -2118,7 +2165,7 @@ async function loadBlips() {
         let url = `${API}/api/events?bbox=${currentBBox()}&has_coords=true&limit=500`;
         const since = sinceToISO(blipsSince);
         if (since) url += `&since=${encodeURIComponent(since)}`;
-        const r = await fetch(url);
+        const r = await overlayFetch(url);
         const evs = (await r.json()).filter(ev => ev.source_type !== 'camera');
         if (req !== blipReq) return; // superseded by a newer pan/zoom
         if (blipsGroup) map.removeLayer(blipsGroup);
@@ -2148,6 +2195,7 @@ async function loadBlips() {
                 `${evs.length.toLocaleString()} event blips in view`;
         }
     } catch(e) {
+        if (isAbort(e)) return;
         document.getElementById('map-hint').textContent = `Blips load failed: ${e.message || e}`;
         console.error('Blips load failed', e);
     }
@@ -2175,6 +2223,14 @@ function dropLayer(ref) {
     if (ref && map && map.hasLayer(ref)) map.removeLayer(ref);
     return null;
 }
+/* Polygon/camera layers hitch at world scale. Same idea as aircraft's zoom<=3
+   skip: do not fetch or render these until the user is zoomed in. */
+const HEAVY_MIN_ZOOM = 4;
+function tooZoomedOut() { return !map || map.getZoom() <= HEAVY_MIN_ZOOM; }
+function markZoom(id) {
+    const el = document.getElementById(id);
+    if (el) el.textContent = 'zoom';
+}
 function intersectsConus() {
     if (!map) return false;
     const b = map.getBounds();
@@ -2251,33 +2307,69 @@ function feedIcon(feed, color, heading) {
     }
     return ic;
 }
+function makePointMarker(p, colorFn, feed, renderer) {
+    if (p.lat == null || p.lon == null) return null;
+    const col = sanitizeColor(colorFn(p), '#35e0ff');
+    if (feed) {
+        const heading = Number(p.heading);
+        const icon = feedIcon(feed, col, Number.isNaN(heading) ? null : heading);
+        return L.marker([p.lat, p.lon], { icon }).bindPopup(() => pointPopup(p));
+    }
+    return L.circleMarker([p.lat, p.lon], {
+        radius: 5, color: col, fillColor: col, fillOpacity: 0.9, weight: 1,
+        renderer,
+    }).bindPopup(() => pointPopup(p));
+}
 function renderPoints(existing, points, colorFn, cluster, feed) {
-    if (existing) map.removeLayer(existing);
     const zoom = map.getZoom();
     const useCluster = cluster && (zoom < 7 || points.length > 200);
-    const group = useCluster
-        ? L.markerClusterGroup({ maxClusterRadius: 48, showCoverageOnHover: false, spiderfyOnMaxZoom: true, chunkedLoading: true })
-        : L.layerGroup();
+    const canReuse = existing && map.hasLayer(existing)
+        && !!existing._osintCluster === !!useCluster
+        && existing._osintById;
+    if (!canReuse) {
+        if (existing) map.removeLayer(existing);
+        const group = useCluster
+            ? L.markerClusterGroup({ maxClusterRadius: 48, showCoverageOnHover: false, spiderfyOnMaxZoom: true, chunkedLoading: true })
+            : L.layerGroup();
+        group._osintCluster = !!useCluster;
+        group._osintById = new Map();
+        const renderer = pointCanvas();
+        points.forEach(p => {
+            const m = makePointMarker(p, colorFn, feed, renderer);
+            if (!m) return;
+            group.addLayer(m);
+            if (p.id != null) group._osintById.set(String(p.id), m);
+        });
+        group.addTo(map);
+        return group;
+    }
+    const group = existing;
+    const byId = group._osintById;
+    const next = new Set();
     const renderer = pointCanvas();
     points.forEach(p => {
-        if (p.lat == null || p.lon == null) return;
+        if (p.lat == null || p.lon == null || p.id == null) return;
+        const id = String(p.id);
+        next.add(id);
         const col = sanitizeColor(colorFn(p), '#35e0ff');
-        if (feed) {
-            const heading = Number(p.heading);
-            const icon = feedIcon(feed, col, Number.isNaN(heading) ? null : heading);
-            const m = L.marker([p.lat, p.lon], { icon }).bindPopup(pointPopup(p));
-            group.addLayer(m);
+        const m = byId.get(id);
+        if (m) {
+            m.setLatLng([p.lat, p.lon]);
+            if (feed) m.setIcon(feedIcon(feed, col, p.heading));
+            else if (m.setStyle) m.setStyle({ color: col, fillColor: col });
         } else {
-            const heading = Number(p.heading);
-            const m = L.circleMarker([p.lat, p.lon], {
-                radius: 5, color: col, fillColor: col, fillOpacity: 0.9, weight: 1,
-                renderer,
-            }).bindPopup(pointPopup(p));
-            if (!Number.isNaN(heading)) m.setStyle({ className: 'hdg' });
-            group.addLayer(m);
+            const nm = makePointMarker(p, colorFn, feed, renderer);
+            if (!nm) return;
+            group.addLayer(nm);
+            byId.set(id, nm);
+        }
+    });
+    byId.forEach((m, id) => {
+        if (!next.has(id)) {
+            group.removeLayer(m);
+            byId.delete(id);
         }
     });
-    group.addTo(map);
     return group;
 }
 async function toggleRadar() {
@@ -2294,7 +2386,7 @@ async function loadRadar() {
     if (!map) return;
     try {
         if (!radarMeta) {
-            const r = await fetch(`${API}/api/map/radar`);
+            const r = await overlayFetch(`${API}/api/map/radar`);
             radarMeta = await r.json();
             addExtraAttrib('<a href="https://www.rainviewer.com/api.html">Weather data by RainViewer</a>');
             addExtraAttrib('Iowa Environmental Mesonet');
@@ -2313,6 +2405,7 @@ async function loadRadar() {
             radarLayer = L.tileLayer(url, { opacity: radarOpacity, maxZoom: 12, maxNativeZoom: useIem ? 18 : 7, attribution: '' }).addTo(map);
         }
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Radar load failed', e);
         document.getElementById('lp-radar-count').textContent = 'err';
     }
@@ -2338,14 +2431,20 @@ async function toggleWxAlerts() {
 }
 async function loadWxAlerts() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        wxAlertsGroup = dropLayer(wxAlertsGroup);
+        markZoom('lp-alerts-count');
+        return;
+    }
     const req = ++overlayReq.alerts;
     try {
-        const r = await fetch(`${API}/api/weather-alerts?bbox=${currentBBox()}`);
+        const r = await overlayFetch(`${API}/api/weather-alerts?bbox=${currentBBox()}`);
         const fc = await r.json();
         if (req !== overlayReq.alerts) return;
         wxAlertsGroup = dropLayer(wxAlertsGroup);
         const feats = fc.features || [];
         wxAlertsGroup = L.geoJSON(fc, {
+            renderer: L.canvas({ padding: 0.5 }),
             style: (f) => ({
                 color: severityColor((f.properties || {}).severity),
                 weight: 2, fillOpacity: 0.18,
@@ -2358,6 +2457,7 @@ async function loadWxAlerts() {
         document.getElementById('lp-alerts-count').textContent = feats.length.toLocaleString();
         addExtraAttrib('NWS / IEM storm-based warnings');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Alerts load failed', e);
         document.getElementById('lp-alerts-count').textContent = 'err';
     }
@@ -2369,14 +2469,20 @@ async function togglePerimeters() {
 }
 async function loadPerimeters() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        perimGroup = dropLayer(perimGroup);
+        markZoom('lp-perim-count');
+        return;
+    }
     const req = ++overlayReq.perim;
     try {
-        const r = await fetch(`${API}/api/fire-perimeters?bbox=${currentBBox()}`);
+        const r = await overlayFetch(`${API}/api/fire-perimeters?bbox=${currentBBox()}`);
         const fc = await r.json();
         if (req !== overlayReq.perim) return;
         perimGroup = dropLayer(perimGroup);
         const feats = fc.features || [];
         perimGroup = L.geoJSON(fc, {
+            renderer: L.canvas({ padding: 0.5 }),
             style: (f) => {
                 const acres = Number((f.properties || {}).poly_GISAcres || (f.properties || {}).attr_IncidentSize || 0);
                 return { color: acres > 10000 ? '#ef4444' : '#fb923c', weight: 2, fillOpacity: 0.25, fillColor: '#fb923c' };
@@ -2391,6 +2497,7 @@ async function loadPerimeters() {
         document.getElementById('lp-perim-count').textContent = feats.length.toLocaleString();
         addExtraAttrib('NIFC WFIGS');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Perimeters load failed', e);
         document.getElementById('lp-perim-count').textContent = 'err';
     }
@@ -2402,15 +2509,21 @@ async function toggleIncidents() {
 }
 async function loadIncidents() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        incidentsGroup = dropLayer(incidentsGroup);
+        markZoom('lp-incidents-count');
+        return;
+    }
     const req = ++overlayReq.incidents;
     try {
-        const r = await fetch(`${API}/api/fire-incidents?bbox=${currentBBox()}`);
+        const r = await overlayFetch(`${API}/api/fire-incidents?bbox=${currentBBox()}`);
         const pts = await r.json();
         if (req !== overlayReq.incidents) return;
         incidentsGroup = renderPoints(incidentsGroup, pts, () => '#ef4444', false);
         document.getElementById('lp-incidents-count').textContent = pts.length.toLocaleString();
         addExtraAttrib('NIFC WFIGS');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Incidents load failed', e);
         document.getElementById('lp-incidents-count').textContent = 'err';
     }
@@ -2428,13 +2541,14 @@ async function loadAircraft() {
     }
     const req = ++overlayReq.ac;
     try {
-        const r = await fetch(`${API}/api/aircraft?bbox=${currentBBox()}`);
+        const r = await overlayFetch(`${API}/api/aircraft?bbox=${currentBBox()}`);
         const pts = await r.json();
         if (req !== overlayReq.ac) return;
         acGroup = renderPoints(acGroup, Array.isArray(pts) ? pts : [], p => altColor((p.extra || {}).alt_baro), true, 'ac');
         document.getElementById('lp-ac-count').textContent = (pts.length || 0).toLocaleString();
         addExtraAttrib('<a href="https://www.adsb.lol/docs/open-data/api">ADSB.lol</a> ODbL');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Aircraft load failed', e);
         document.getElementById('lp-ac-count').textContent = 'err';
     }
@@ -2448,13 +2562,14 @@ async function loadTrains() {
     if (!map) return;
     const req = ++overlayReq.trains;
     try {
-        const r = await fetch(`${API}/api/trains?bbox=${currentBBox()}`);
+        const r = await overlayFetch(`${API}/api/trains?bbox=${currentBBox()}`);
         const pts = await r.json();
         if (req !== overlayReq.trains) return;
         trainsGroup = renderPoints(trainsGroup, Array.isArray(pts) ? pts : [], p => (p.extra || {}).iconColor || '#c084fc', false, 'train');
         document.getElementById('lp-trains-count').textContent = (pts.length || 0).toLocaleString();
         addExtraAttrib('<a href="https://amtraker.com/about">Amtraker</a>');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Trains load failed', e);
         document.getElementById('lp-trains-count').textContent = 'err';
     }
@@ -2472,7 +2587,7 @@ async function loadVessels() {
     }
     const req = ++overlayReq.vessels;
     try {
-        const r = await fetch(`${API}/api/vessels?bbox=${currentBBox()}`);
+        const r = await overlayFetch(`${API}/api/vessels?bbox=${currentBBox()}`);
         const pts = await r.json();
         if (req !== overlayReq.vessels) return;
         vesselsGroup = renderPoints(vesselsGroup, Array.isArray(pts) ? pts : [], p => {
@@ -2482,6 +2597,7 @@ async function loadVessels() {
         document.getElementById('lp-vessels-count').textContent = (pts.length || 0).toLocaleString();
         addExtraAttrib('AISStream');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Vessels load failed', e);
         document.getElementById('lp-vessels-count').textContent = 'err';
     }
@@ -2495,13 +2611,14 @@ async function loadStorms() {
     if (!map) return;
     const req = ++overlayReq.storms;
     try {
-        const r = await fetch(`${API}/api/storms`);
+        const r = await overlayFetch(`${API}/api/storms`);
         const pts = await r.json();
         if (req !== overlayReq.storms) return;
         stormsGroup = renderPoints(stormsGroup, Array.isArray(pts) ? pts : [], () => '#f472b6', false);
         document.getElementById('lp-storms-count').textContent = (pts.length || 0).toLocaleString();
         addExtraAttrib('NHC');
     } catch (e) {
+        if (isAbort(e)) return;
         console.error('Storms load failed', e);
         document.getElementById('lp-storms-count').textContent = 'err';
     }
@@ -2511,9 +2628,9 @@ async function loadStorms() {
 initNav();
 initSettings();
 initMarketTicker();
-loadSummary(); loadEvents(); loadNews(true); checkHealth();
-setInterval(() => { loadSummary(); loadEvents(); checkHealth(); }, 30000);
+checkHealth();
 initMap();
+setInterval(checkHealth, 30000);
 </script>
 </body>
 </html>
diff --git a/tests/test_api_live_layers.py b/tests/test_api_live_layers.py
index a9e2c1d..ec17da8 100644
--- a/tests/test_api_live_layers.py
+++ b/tests/test_api_live_layers.py
@@ -36,3 +36,4 @@ def test_vessels_empty_without_ais_key():
     resp = asyncio.run(_get("/api/vessels"))
     assert resp.status_code == 200
     assert resp.json() == []
+    assert "max-age" in (resp.headers.get("cache-control") or "").lower()
diff --git a/tests/test_live_layers.py b/tests/test_live_layers.py
index 2214a5c..fedf6dd 100644
--- a/tests/test_live_layers.py
+++ b/tests/test_live_layers.py
@@ -3,15 +3,21 @@
 from live_layers import (
     MARKER_FIELDS,
     bbox_center_radius_nm,
+    clip_fc_to_bbox,
     filter_points_bbox,
     parse_bbox,
+    quantize_bbox,
     rainviewer_tile_url,
+    slim_alert_properties,
     to_marker,
     transform_adsb_lol,
     transform_ais_frame,
     transform_amtraker,
     transform_nhc_storms,
     transform_wfigs_incidents,
+    _cache,
+    _ttl_get,
+    _wfigs_params,
 )
 
 from camera_scraper import parse_caltrans_json
@@ -244,3 +250,115 @@ def test_parse_caltrans_skips_oos_and_maps_jpeg_hls():
     assert "I-80" in cam["location_name"]
     assert "rtsp://" not in cam["source_url"].lower()
     assert "rtsp://" not in cam["snapshot_url"].lower()
+
+
+def test_quantize_bbox_stable_under_jitter():
+    a = quantize_bbox(*parse_bbox("-78.7912,35.7711,-78.6101,35.9102"))
+    b = quantize_bbox(*parse_bbox("-78.7900,35.7700,-78.6110,35.9090"))
+    assert a == b
+    minlon, minlat, maxlon, maxlat = a
+    assert minlon <= -78.7912
+    assert minlat <= 35.7700
+    assert maxlon >= -78.6101
+    assert maxlat >= 35.9102
+
+
+def test_ttl_get_does_not_block_other_keys():
+    import asyncio
+
+    _cache.clear()
+    order = []
+
+    async def slow():
+        order.append("slow-start")
+        await asyncio.sleep(0.2)
+        order.append("slow-end")
+        return "S"
+
+    async def fast():
+        order.append("fast")
+        return "F"
+
+    async def run():
+        t1 = asyncio.create_task(_ttl_get("slow", 5, slow))
+        await asyncio.sleep(0.01)
+        t2 = asyncio.create_task(_ttl_get("fast", 5, fast))
+        await asyncio.gather(t1, t2)
+
+    asyncio.run(run())
+    assert order.index("fast") < order.index("slow-end")
+    assert _cache["slow"][1] == "S"
+    assert _cache["fast"][1] == "F"
+    _cache.clear()
+
+
+def test_clip_fc_to_bbox_drops_far_features_and_empty_geometry():
+    fc = {
+        "type": "FeatureCollection",
+        "features": [
+            {
+                "type": "Feature",
+                "properties": {"event": "near"},
+                "geometry": {"type": "Point", "coordinates": [-78.7, 35.8]},
+            },
+            {
+                "type": "Feature",
+                "properties": {"event": "far"},
+                "geometry": {"type": "Point", "coordinates": [-120.0, 45.0]},
+            },
+            {
+                "type": "Feature",
+                "properties": {"event": "nogeom"},
+                "geometry": None,
+            },
+            {
+                "type": "Feature",
+                "properties": {"event": "poly-overlap"},
+                "geometry": {
+                    "type": "Polygon",
+                    "coordinates": [[
+                        [-79.0, 35.0], [-78.0, 35.0], [-78.0, 36.0],
+                        [-79.0, 36.0], [-79.0, 35.0],
+                    ]],
+                },
+            },
+        ],
+    }
+    clipped = clip_fc_to_bbox(fc, -79.0, 35.5, -78.0, 36.0)
+    events = [f["properties"]["event"] for f in clipped["features"]]
+    assert events == ["near", "poly-overlap"]
+
+
+def test_slim_alert_properties_keeps_popup_fields_only():
+    fat = {
+        "event": "Tornado Warning",
+        "severity": "Extreme",
+        "headline": "TORNADO WARNING",
+        "areaDesc": "Wake",
+        "wfo": "RAH",
+        "source": "nws",
+        "parameters": {"WIND": ["70"]},
+        "description": "A long narrative " * 40,
+        "instruction": "Take shelter.",
+        "geocode": {"SAME": ["037183"]},
+    }
+    slim = slim_alert_properties(fat)
+    assert slim == {
+        "event": "Tornado Warning",
+        "severity": "Extreme",
+        "headline": "TORNADO WARNING",
+        "areaDesc": "Wake",
+        "wfo": "RAH",
+        "source": "nws",
+    }
+
+
+def test_wfigs_params_requests_simplified_geometry():
+    params = _wfigs_params("-84.5,33.8,-75.4,36.6")
+    assert "maxAllowableOffset" in params
+    assert float(params["maxAllowableOffset"]) > 0
+    assert params["geometryPrecision"] == 5
+    assert int(params["resultRecordCount"]) <= 500
+    # Envelope is the quantized cell, not the raw pan box.
+    geom = params["geometry"]
+    assert geom != "-84.5,33.8,-75.4,36.6"
diff --git a/tests/test_map_payloads.py b/tests/test_map_payloads.py
new file mode 100644
index 0000000..982aeb6
--- /dev/null
+++ b/tests/test_map_payloads.py
@@ -0,0 +1,47 @@
+"""Slim map-payload helpers (no DB)."""
+
+from uuid import uuid4
+
+from main import camera_map_row, fire_heat_row
+
+
+def test_fire_heat_row_is_tiny():
+    row = {
+        "latitude": 35.0,
+        "longitude": -78.0,
+        "brightness": 340.1,
+        "confidence": "h",
+        "satellite": "N21",
+        "acq_time": "2026-08-27T00:00:00Z",
+        "instrument": "VIIRS",
+        "frp": 12.4,
+    }
+    out = fire_heat_row(row)
+    assert out == {"lat": 35.0, "lon": -78.0, "i": 340.1, "c": "h"}
+    assert "satellite" not in out
+    assert "frp" not in out
+
+
+def test_camera_map_row_omits_urls():
+    cid = uuid4()
+    row = {
+        "id": cid,
+        "location_lat": 37.8,
+        "location_lon": -122.4,
+        "device_type": "hls",
+        "discovery_source": "caltrans",
+        "location_name": "I-80 WB",
+        "source_url": "https://example.invalid/playlist.m3u8",
+        "snapshot_url": "https://example.invalid/cam.jpg",
+        "vendor": "Caltrans",
+        "first_seen": None,
+        "last_seen": None,
+    }
+    out = camera_map_row(row)
+    assert out["id"] == str(cid)
+    assert out["lat"] == 37.8
+    assert out["lon"] == -122.4
+    assert out["device_type"] == "hls"
+    assert "source_url" not in out
+    assert "snapshot_url" not in out
+    assert "vendor" not in out