diff --git a/base-config.yaml b/base-config.yaml
index bf4c69a..7f77244 100644
--- a/base-config.yaml
+++ b/base-config.yaml
@@ -6,7 +6,15 @@ space_id: "!vervang-mij:example.org"
 # Hoe diep de bot in geneste subspaces mag kijken.
 max_depth: 5
 
+# Hoeveel rooms er per bericht getoond worden (Matrix-events hebben een max grootte,
+# dus bij ~200 rooms wordt de lijst automatisch over meerdere berichten verdeeld).
+rooms_per_message: 50
 
 # Harde bovengrens voor het totale aantal rooms dat wordt opgehaald/verstuurd.
 # Voorkomt dat een enorme (gefedereerde) space-boom leidt tot duizenden berichten.
 max_rooms: 300
+
+# Hoe lang (minuten) de opgehaalde lijst wordt gecached in de plugin-database.
+# Binnen deze periode gebruikt !rooms de cache i.p.v. de hele boom opnieuw op te
+# halen (minder traffic naar de homeserver en federatie). 0 = caching uit.
+cache_ttl_minutes: 15
\ No newline at end of file
diff --git a/maubot.yaml b/maubot.yaml
index caa892e..73e7ec2 100644
--- a/maubot.yaml
+++ b/maubot.yaml
@@ -1,10 +1,12 @@
 maubot: 0.1.0
 id: nl.roomsoverview
-version: 1.0.4
+version: 1.0.5
 license: MIT
 modules:
   - roomsoverview
 main_class: RoomsOverviewPlugin
+database: true
+database_type: asyncpg
 config: true
 extra_files:
   - base-config.yaml
diff --git a/roomsoverview.mbp b/roomsoverview.mbp
index 7520615..9e98239 100644
Binary files a/roomsoverview.mbp and b/roomsoverview.mbp differ
diff --git a/roomsoverview.py b/roomsoverview.py
index cfd1c55..3dad5df 100644
--- a/roomsoverview.py
+++ b/roomsoverview.py
@@ -1,4 +1,6 @@
 import asyncio
+import json
+import time
 from typing import Any, Dict, List, Optional, Tuple
 from urllib.parse import quote
 
@@ -6,10 +8,35 @@ import aiohttp
 
 from maubot import Plugin, MessageEvent
 from maubot.handlers import command
+from mautrix.util.async_db import Connection, Scheme, UpgradeTable
 from mautrix.util.config import BaseProxyConfig, ConfigUpdateHelper
 
 _REQUEST_TIMEOUT = aiohttp.ClientTimeout(total=30)
 
+upgrade_table = UpgradeTable()
+
+
+@upgrade_table.register(description="Initial revision")
+async def upgrade_v1(conn: Connection, scheme: Scheme) -> None:
+    if scheme == Scheme.SQLITE:
+        await conn.execute(
+            """CREATE TABLE roomsoverview_cache (
+                space_id TEXT PRIMARY KEY,
+                rooms TEXT NOT NULL,
+                complete INTEGER NOT NULL,
+                fetched_at BIGINT NOT NULL
+            )"""
+        )
+    else:
+        await conn.execute(
+            """CREATE TABLE roomsoverview_cache (
+                space_id TEXT PRIMARY KEY,
+                rooms TEXT NOT NULL,
+                complete BOOLEAN NOT NULL,
+                fetched_at BIGINT NOT NULL
+            )"""
+        )
+
 
 def _escape_md(text: str) -> str:
     """Escape markdown-significant characters when embedding user content."""
@@ -31,6 +58,7 @@ class Config(BaseProxyConfig):
         helper.copy("max_depth")
         helper.copy("rooms_per_message")
         helper.copy("max_rooms")
+        helper.copy("cache_ttl_minutes")
 
 
 class RoomsOverviewPlugin(Plugin):
@@ -41,6 +69,10 @@ class RoomsOverviewPlugin(Plugin):
     def get_config_class(cls):
         return Config
 
+    @classmethod
+    def get_db_upgrade_table(cls) -> UpgradeTable:
+        return upgrade_table
+
     async def _fetch_hierarchy(self, space_id: str) -> Tuple[List[Dict[str, Any]], bool]:
         """Fetch the paginated space hierarchy for a room.
 
@@ -123,6 +155,31 @@ class RoomsOverviewPlugin(Plugin):
                 break
         return rooms, True
 
+    async def _load_cache(
+        self, space_id: str
+    ) -> Optional[Tuple[List[Dict[str, Any]], bool, int]]:
+        row = await self.database.fetchrow(
+            "SELECT rooms, complete, fetched_at FROM roomsoverview_cache "
+            "WHERE space_id = $1",
+            space_id,
+        )
+        if not row:
+            return None
+        return json.loads(row["rooms"]), bool(row["complete"]), int(row["fetched_at"])
+
+    async def _store_cache(
+        self, space_id: str, rooms: List[Dict[str, Any]], complete: bool
+    ) -> None:
+        await self.database.execute(
+            "INSERT INTO roomsoverview_cache (space_id, rooms, complete, fetched_at) "
+            "VALUES ($1, $2, $3, $4) "
+            "ON CONFLICT (space_id) DO UPDATE SET rooms = $2, complete = $3, fetched_at = $4",
+            space_id,
+            json.dumps(rooms, ensure_ascii=False),
+            complete,
+            int(time.time()),
+        )
+
     @command.new(name="rooms", help="Toon alle rooms in de geconfigureerde space")
     async def handle_rooms(self, evt: MessageEvent) -> None:
         space_id = str(self.config.get("space_id", "") or "")
@@ -133,14 +190,24 @@ class RoomsOverviewPlugin(Plugin):
             return
 
         await evt.mark_read()
-        entries, complete = await self._fetch_hierarchy(space_id)
 
-        rooms = [
-            r
-            for r in entries
-            if r.get("room_id") != space_id
-            and (r.get("room_type") or "") != "m.space"
-        ]
+        ttl_minutes = max(0, int(self.config.get("cache_ttl_minutes", 15) or 15))
+        cached = await self._load_cache(space_id)
+        now = int(time.time())
+        if cached and ttl_minutes > 0 and now - cached[2] < ttl_minutes * 60:
+            rooms, complete = cached[0], cached[1]
+            self.log.info(
+                f"rooms: cache hit voor {space_id} (age {now - cached[2]}s)"
+            )
+        else:
+            entries, complete = await self._fetch_hierarchy(space_id)
+            rooms = [
+                r
+                for r in entries
+                if r.get("room_id") != space_id
+                and (r.get("room_type") or "") != "m.space"
+            ]
+            await self._store_cache(space_id, rooms, complete)
 
         if not rooms:
             if not complete: