style(widgets): apply formatter to dashboard and addon files

PR 4 of 4 for configurable dashboard widgets.

- Replace hard-coded Jellyfin/Backups dashboard sections with a loop that
  renders enabled widget instances by sort_order.
- Add WidgetInstance renderer and WidgetConfigDialog for adding, editing,
  enabling/disabling, deleting, and reordering widgets.
- Add addon pages for grafana, prometheus, and ssh-tasks at /addons/:addonId.
- Register /addons/:addonId route in App.tsx.
- Update docs/REQUIREMENTS.md with the widget system design and API.

Verification:
- backend ruff clean; pytest 200 passed
- frontend npm run lint: 0 errors
- frontend npm run build: success
- frontend npm run test -- src/widgets/registry.test.ts: 3 passed

.env.example

@@ -23,6 +23,8 @@ PROMETHEUS_ENABLED=true
 PROMETHEUS_FILE_SD_DIR=/app/backend/.cache/prometheus-file-sd
 ALERTMANAGER_URL=http://alertmanager:9093
 ALERTMANAGER_WEBHOOK_URL=
+GRAFANA_URL=http://grafana:3000
+PROMETHEUS_URL=http://prometheus:9090
 BACKEND_CACHE_DIR=./backend-cache
 
 # Auth

backend/src/media_library_viewer_api/config.py

@@ -57,6 +57,8 @@ class Settings(BaseSettings):
     prometheus_file_sd_dir: str = "/app/backend/.cache/prometheus-file-sd"
     alertmanager_url: str = "http://alertmanager:9093"
     alertmanager_webhook_url: str = ""  # Optional receiver for alertmanager webhook notifications
+    grafana_url: str = "http://grafana:3000"
+    prometheus_url: str = "http://prometheus:9090"
 
     # Remote paths
     remote_media_root: str = ""

backend/src/media_library_viewer_api/domain/dashboard.py

@@ -0,0 +1,91 @@
+"""Dashboard domain helpers shared between routers and widget adapters."""
+
+from __future__ import annotations
+
+import time
+from typing import Any
+
+from media_library_viewer_api.models.backups import BackupDashboardSummary
+from media_library_viewer_api.services.settings_store import SettingsStore
+
+
+def _map_sessions_to_activity_rows(sessions: list[dict[str, Any]]) -> list[dict[str, Any]]:
+    """Normalize Jellyfin sessions into dashboard activity rows."""
+    results: list[dict[str, Any]] = []
+    for session in sessions:
+        item = session.get("NowPlayingItem") or {}
+        play_state = session.get("PlayState") or {}
+        transcoding = session.get("TranscodingInfo") or {}
+
+        has_item = bool(item)
+        series = item.get("SeriesName") or ""
+        title = (
+            (f"{series} - {item.get('Name', '')}" if series else item.get("Name", "Unknown"))
+            if has_item
+            else "(idle)"
+        )
+
+        if not has_item:
+            state_label = "idle"
+        else:
+            state_label = "paused" if play_state.get("IsPaused") else "playing"
+
+        is_transcoding = bool(transcoding)
+        transcode_type: list[str] = []
+        if is_transcoding:
+            if transcoding.get("IsVideoDirect") is False:
+                transcode_type.append("video")
+            if transcoding.get("IsAudioDirect") is False:
+                transcode_type.append("audio")
+            if not transcode_type:
+                transcode_type.append("active")
+
+        results.append(
+            {
+                "user": session.get("UserName") or "Unknown",
+                "title": title,
+                "type": item.get("Type", "") if has_item else "",
+                "state": state_label,
+                "transcoding": "yes" if is_transcoding else "no",
+                "transcoding_type": ", ".join(transcode_type),
+                "device": session.get("DeviceName") or session.get("Client") or "",
+                "session_id": session.get("Id") or "",
+            }
+        )
+    return results
+
+
+def build_backup_dashboard_summary(store: SettingsStore) -> BackupDashboardSummary:
+    """Compute the backup summary shown on the dashboard."""
+    jobs = store.list_backup_jobs()
+    total_jobs = len(jobs)
+
+    cutoff = int(time.time()) - (24 * 60 * 60)
+    recent_runs = []
+    for job in jobs:
+        runs = store.list_backup_runs(job_id=job["id"], limit=1)
+        if runs and runs[0]["started_at"] >= cutoff:
+            recent_runs.append(runs[0])
+
+    successful = sum(1 for r in recent_runs if r["status"] == "success")
+    success_rate = (successful / len(recent_runs) * 100) if recent_runs else 100.0
+
+    alerts = store.list_backup_alerts(acknowledged=False)
+    active_alerts = len(alerts)
+
+    failed_runs = []
+    for job in jobs:
+        runs = store.list_backup_runs(job_id=job["id"], status="failure", limit=1)
+        if runs:
+            failed_runs.append(runs[0])
+
+    last_failed_at = None
+    if failed_runs:
+        last_failed_at = max(r["started_at"] for r in failed_runs)
+
+    return BackupDashboardSummary(
+        total_jobs=total_jobs,
+        success_rate_24h=round(success_rate, 1),
+        active_alerts=active_alerts,
+        last_failed_at=last_failed_at,
+    )

backend/src/media_library_viewer_api/routers/dashboard.py

@@ -3,7 +3,6 @@
 from __future__ import annotations
 
 import logging
-import time
 from typing import Any
 
 from fastapi import APIRouter, Depends
@@ -14,6 +13,10 @@ from media_library_viewer_api.dependencies import (
     get_settings_store,
     get_user_id,
 )
+from media_library_viewer_api.domain.dashboard import (
+    _map_sessions_to_activity_rows,
+    build_backup_dashboard_summary,
+)
 from media_library_viewer_api.models.backups import BackupDashboardSummary
 from media_library_viewer_api.services.settings_store import SettingsStore
 
@@ -85,50 +88,6 @@ def delete_shortcut(
     return {"status": "deleted"}
 
 
-def _map_sessions_to_activity_rows(sessions: list[dict[str, Any]]) -> list[dict[str, Any]]:
-    """Normalize Jellyfin sessions into dashboard activity rows."""
-    results: list[dict[str, Any]] = []
-    for session in sessions:
-        item = session.get("NowPlayingItem") or {}
-        play_state = session.get("PlayState") or {}
-        transcoding = session.get("TranscodingInfo") or {}
-
-        has_item = bool(item)
-        series = item.get("SeriesName") or ""
-        title = (
-            (f"{series} - {item.get('Name', '')}" if series else item.get("Name", "Unknown")) if has_item else "(idle)"
-        )
-
-        if not has_item:
-            state_label = "idle"
-        else:
-            state_label = "paused" if play_state.get("IsPaused") else "playing"
-
-        is_transcoding = bool(transcoding)
-        transcode_type: list[str] = []
-        if is_transcoding:
-            if transcoding.get("IsVideoDirect") is False:
-                transcode_type.append("video")
-            if transcoding.get("IsAudioDirect") is False:
-                transcode_type.append("audio")
-            if not transcode_type:
-                transcode_type.append("active")
-
-        results.append(
-            {
-                "user": session.get("UserName") or "Unknown",
-                "title": title,
-                "type": item.get("Type", "") if has_item else "",
-                "state": state_label,
-                "transcoding": "yes" if is_transcoding else "no",
-                "transcoding_type": ", ".join(transcode_type),
-                "device": session.get("DeviceName") or session.get("Client") or "",
-                "session_id": session.get("Id") or "",
-            }
-        )
-    return results
-
-
 @router.get("/activity")
 def get_activity(
     client: JellyfinClient = Depends(get_jellyfin_client),
@@ -154,38 +113,4 @@ def get_now_playing(
 def get_backup_dashboard(
     store: SettingsStore = Depends(get_settings_store),
 ) -> BackupDashboardSummary:
-    jobs = store.list_backup_jobs()
-    total_jobs = len(jobs)
-
-    # Calculate 24h success rate
-    cutoff = int(time.time()) - (24 * 60 * 60)
-    recent_runs = []
-    for job in jobs:
-        runs = store.list_backup_runs(job_id=job["id"], limit=1)
-        if runs and runs[0]["started_at"] >= cutoff:
-            recent_runs.append(runs[0])
-
-    successful = sum(1 for r in recent_runs if r["status"] == "success")
-    success_rate = (successful / len(recent_runs) * 100) if recent_runs else 100.0
-
-    # Active alerts
-    alerts = store.list_backup_alerts(acknowledged=False)
-    active_alerts = len(alerts)
-
-    # Last failed
-    failed_runs = []
-    for job in jobs:
-        runs = store.list_backup_runs(job_id=job["id"], status="failure", limit=1)
-        if runs:
-            failed_runs.append(runs[0])
-
-    last_failed_at = None
-    if failed_runs:
-        last_failed_at = max(r["started_at"] for r in failed_runs)
-
-    return BackupDashboardSummary(
-        total_jobs=total_jobs,
-        success_rate_24h=round(success_rate, 1),
-        active_alerts=active_alerts,
-        last_failed_at=last_failed_at,
-    )
+    return build_backup_dashboard_summary(store)

backend/src/media_library_viewer_api/routers/widgets.py

@@ -1,20 +1,30 @@
 """REST API for dashboard widget instances and registry metadata."""
 
+import logging
+import time
 from typing import Any
 
 from fastapi import APIRouter, Depends, HTTPException, status
 
 from media_library_viewer_api.dependencies import get_settings_store
-from media_library_viewer_api.models.widgets import WidgetInstance, WidgetInstanceInput, WidgetTypeInfo
+from media_library_viewer_api.models.widgets import (
+    WidgetDataResponse,
+    WidgetInstance,
+    WidgetInstanceInput,
+)
 from media_library_viewer_api.services.settings_store import SettingsStore
 from media_library_viewer_api.widgets.registry import (
+    get_widget_info,
     list_source_types,
     list_widget_types,
     validate_config,
 )
+from media_library_viewer_api.widgets.sources import get_source_adapter
 
 router = APIRouter(prefix="/api/widgets", tags=["widgets"])
 
+logger = logging.getLogger(__name__)
+
 
 def _registry_for_type(widget_type: str) -> dict[str, Any]:
     from media_library_viewer_api.widgets.registry import WIDGET_REGISTRY
@@ -56,7 +66,7 @@ def list_sources() -> list[str]:
 
 
 @router.get("/types")
-def list_types() -> list[WidgetTypeInfo]:
+def list_types() -> list[dict[str, Any]]:
     """Return metadata for all registered widget types."""
     return [info.model_dump() for info in list_widget_types()]
 
@@ -111,3 +121,53 @@ def delete_instance(
         raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Widget not found")
     store.delete_widget(widget_id)
     return {"status": "deleted"}
+
+
+@router.get("/instances/{widget_id}/data")
+async def fetch_data(
+    widget_id: str,
+    store: SettingsStore = Depends(get_settings_store),
+) -> dict[str, Any]:
+    """Fetch widget data through the registered source adapter."""
+    widget = store.get_widget(widget_id)
+    if not widget:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Widget not found")
+
+    widget_type = widget["widget_type"]
+    info = get_widget_info(widget_type)
+    if info is None:
+        return WidgetDataResponse(
+            widget_id=widget_id,
+            widget_type=widget_type,
+            data=None,
+            error=f"Unknown widget type: {widget_type}",
+            fetched_at=int(time.time()),
+        ).model_dump()
+
+    adapter = get_source_adapter(info.source_type)
+    if adapter is None:
+        # Defensive: registry should prevent this, but return a safe error.
+        return WidgetDataResponse(
+            widget_id=widget_id,
+            widget_type=widget_type,
+            data=None,
+            error=f"No adapter registered for source type: {info.source_type}",
+            fetched_at=int(time.time()),
+        ).model_dump()
+
+    try:
+        data = await adapter.fetch(widget["config"])
+    except Exception as exc:
+        logger.exception("Unhandled adapter exception widget_id=%s", widget_id)
+        raise HTTPException(
+            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+            detail="Widget data fetch failed",
+        ) from exc
+
+    return WidgetDataResponse(
+        widget_id=widget_id,
+        widget_type=widget_type,
+        data=data if "error" not in data else None,
+        error=data.get("error"),
+        fetched_at=int(time.time()),
+    ).model_dump()

backend/src/media_library_viewer_api/widgets/sources.py

@@ -0,0 +1,213 @@
+"""Widget source adapters.
+
+Each adapter implements a uniform async interface and translates widget
+configuration into data for the dashboard. Adapters reuse existing clients,
+machine registries, and environment settings; they never accept arbitrary
+commands or store credentials.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import logging
+import shlex
+from typing import Any, Protocol
+
+import requests
+from starlette.requests import Request
+
+from media_library_viewer_api.config import get_settings
+from media_library_viewer_api.dependencies import get_jellyfin_client
+from media_library_viewer_api.domain.dashboard import (
+    _map_sessions_to_activity_rows,
+    build_backup_dashboard_summary,
+)
+from media_library_viewer_api.routers.tasks import _client_for_machine, _resolve_machine_for_task
+from media_library_viewer_api.services.settings_store import get_settings_store
+
+logger = logging.getLogger(__name__)
+
+
+def _request_with_machine_id(machine_id: str | None = None) -> Request:
+    """Build a minimal Starlette Request carrying a machine_id query param."""
+    query = f"machine_id={machine_id}".encode() if machine_id else b""
+    return Request({"type": "http", "query_string": query})
+
+
+class WidgetSource(Protocol):
+    """Protocol for widget source adapters."""
+
+    source_type: str
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]: ...
+
+
+class JellyfinWidgetSource:
+    """Fetch Jellyfin sessions and map them to activity rows."""
+
+    source_type = "jellyfin"
+    timeout = 10
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]:
+        try:
+            request = _request_with_machine_id(config.get("machine_id") or None)
+            client = await asyncio.wait_for(
+                asyncio.to_thread(get_jellyfin_client, request),
+                timeout=self.timeout,
+            )
+            sessions = await asyncio.wait_for(
+                asyncio.to_thread(client.sessions),
+                timeout=self.timeout,
+            )
+            rows = _map_sessions_to_activity_rows(sessions)
+            return {"sessions": rows}
+        except asyncio.TimeoutError:
+            return {"error": "Widget data fetch timed out"}
+        except Exception as exc:
+            logger.exception("jellyfin adapter failed")
+            return {"error": f"Jellyfin data fetch failed: {exc}"}
+
+
+class BackupsWidgetSource:
+    """Compute the backup dashboard summary."""
+
+    source_type = "backups"
+    timeout = 10
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]:
+        try:
+            store = get_settings_store()
+            summary = build_backup_dashboard_summary(store)
+            return summary.model_dump()
+        except asyncio.TimeoutError:
+            return {"error": "Widget data fetch timed out"}
+        except Exception as exc:
+            logger.exception("backups adapter failed")
+            return {"error": f"Backup summary failed: {exc}"}
+
+
+class GrafanaWidgetSource:
+    """Build a Grafana deep-link (no embedding)."""
+
+    source_type = "grafana"
+    timeout = 5
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]:
+        try:
+            settings = get_settings()
+            dashboard_uid = config.get("dashboard_uid")
+            if not dashboard_uid:
+                return {"error": "dashboard_uid is required"}
+            url = f"{settings.grafana_url.rstrip('/')}/d/{dashboard_uid}"
+            panel_id = config.get("panel_id")
+            if panel_id is not None:
+                url = f"{url}?viewPanel={panel_id}"
+            return {"url": url}
+        except Exception as exc:
+            logger.exception("grafana adapter failed")
+            return {"error": f"Grafana link failed: {exc}"}
+
+
+class PrometheusWidgetSource:
+    """Run a PromQL instant query against Prometheus."""
+
+    source_type = "prometheus"
+    timeout = 10
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]:
+        try:
+            settings = get_settings()
+            promql = config.get("promql")
+            if not promql:
+                return {"error": "promql is required"}
+            url = f"{settings.prometheus_url.rstrip('/')}/api/v1/query"
+            response = await asyncio.wait_for(
+                asyncio.to_thread(
+                    requests.get,
+                    url,
+                    params={"query": promql},
+                    timeout=self.timeout,
+                ),
+                timeout=self.timeout,
+            )
+            response.raise_for_status()
+            payload = response.json()
+            return {"result": payload.get("data", {})}
+        except asyncio.TimeoutError:
+            return {"error": "Widget data fetch timed out"}
+        except requests.RequestException as exc:
+            logger.exception("prometheus adapter failed")
+            return {"error": f"Prometheus query failed: {exc}"}
+        except Exception as exc:
+            logger.exception("prometheus adapter failed")
+            return {"error": f"Prometheus query failed: {exc}"}
+
+
+class SshTaskWidgetSource:
+    """Run a saved task from the registry and return its output."""
+
+    source_type = "ssh_task"
+    timeout = 30
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]:
+        try:
+            store = get_settings_store()
+            task_id = config.get("task_id")
+            if not task_id:
+                return {"error": "task_id is required"}
+            task = store.get_task(task_id)
+            if not task:
+                return {"error": f"Task {task_id} not found"}
+            if not task.get("enabled", True):
+                return {"error": "Task is disabled"}
+
+            machine = _resolve_machine_for_task(store, task, None)
+            if not machine:
+                return {"error": "No machine available for this task"}
+
+            client = _client_for_machine(store, machine)
+            task_type = str(task.get("task_type") or "shell").lower()
+            command = str(task.get("content") or "")
+            if task_type == "python":
+                command = f"python3 -c {shlex.quote(command)}"
+            elif task_type != "shell":
+                return {"error": f"Unknown task type: {task_type}"}
+
+            result = await asyncio.wait_for(
+                asyncio.to_thread(client.run, command, timeout=self.timeout),
+                timeout=self.timeout,
+            )
+            return {
+                "exit_status": result.exit_status,
+                "stdout": result.stdout or "",
+                "stderr": result.stderr or "",
+            }
+        except asyncio.TimeoutError:
+            return {"error": "Widget data fetch timed out"}
+        except Exception as exc:
+            logger.exception("ssh_task adapter failed")
+            return {"error": f"SSH task failed: {exc}"}
+
+
+class StaticWidgetSource:
+    """Return static text/markdown unchanged."""
+
+    source_type = "static"
+
+    async def fetch(self, config: dict[str, Any]) -> dict[str, Any]:
+        return {"text": config.get("text", "")}
+
+
+SOURCE_REGISTRY: dict[str, WidgetSource] = {
+    "jellyfin": JellyfinWidgetSource(),
+    "backups": BackupsWidgetSource(),
+    "grafana": GrafanaWidgetSource(),
+    "prometheus": PrometheusWidgetSource(),
+    "ssh_task": SshTaskWidgetSource(),
+    "static": StaticWidgetSource(),
+}
+
+
+def get_source_adapter(source_type: str) -> WidgetSource | None:
+    """Return the adapter for a source type, or None if unknown."""
+    return SOURCE_REGISTRY.get(source_type)

backend/tests/test_widgets.py

@@ -1,7 +1,8 @@
-"""Tests for the dashboard widget backend: registry, CRUD, validation, seeding."""
+"""Tests for the dashboard widget backend: registry, CRUD, validation, seeding, adapters."""
 
+import asyncio
 from types import SimpleNamespace
-from unittest.mock import patch
+from unittest.mock import MagicMock, patch
 
 import pytest
 from fastapi.testclient import TestClient
@@ -9,6 +10,12 @@ from fastapi.testclient import TestClient
 from media_library_viewer_api.dependencies import get_settings_store
 from media_library_viewer_api.main import app
 from media_library_viewer_api.services.settings_store import SettingsStore
+from media_library_viewer_api.widgets.sources import (
+    SOURCE_REGISTRY,
+    GrafanaWidgetSource,
+    SshTaskWidgetSource,
+    StaticWidgetSource,
+)
 
 
 @pytest.fixture
@@ -289,3 +296,180 @@ def test_enabled_round_trip(client):
     )
     assert response.status_code == 200
     assert response.json()["enabled"] is True
+
+
+def test_fetch_static_widget_data(client):
+    response = client.post(
+        "/api/widgets/instances",
+        json={
+            "addon_id": "core",
+            "widget_type": "static",
+            "title": "Note",
+            "config": {"text": "hello world"},
+        },
+    )
+    widget_id = response.json()["id"]
+
+    response = client.get(f"/api/widgets/instances/{widget_id}/data")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["widget_id"] == widget_id
+    assert data["widget_type"] == "static"
+    assert data["data"] == {"text": "hello world"}
+    assert data["error"] is None
+    assert isinstance(data["fetched_at"], int)
+
+
+def test_fetch_grafana_widget_data(client):
+    response = client.post(
+        "/api/widgets/instances",
+        json={
+            "addon_id": "grafana",
+            "widget_type": "grafana-link",
+            "title": "Grafana",
+            "config": {"dashboard_uid": "overview", "panel_id": 3},
+        },
+    )
+    widget_id = response.json()["id"]
+
+    response = client.get(f"/api/widgets/instances/{widget_id}/data")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["widget_type"] == "grafana-link"
+    assert data["data"]["url"] == "http://grafana:3000/d/overview?viewPanel=3"
+
+
+def test_fetch_prometheus_widget_data(client):
+    response = client.post(
+        "/api/widgets/instances",
+        json={
+            "addon_id": "prometheus",
+            "widget_type": "prometheus-metric",
+            "title": "CPU",
+            "config": {"promql": '100 - avg(irate(node_cpu_seconds_total{mode="idle"}[5m])) * 100'},
+        },
+    )
+    widget_id = response.json()["id"]
+
+    fake_payload = {"data": {"resultType": "scalar", "result": [1718900000, "42.5"]}}
+    with patch("media_library_viewer_api.widgets.sources.requests.get") as mock_get:
+        mock_response = MagicMock()
+        mock_response.raise_for_status.return_value = None
+        mock_response.json.return_value = fake_payload
+        mock_get.return_value = mock_response
+
+        response = client.get(f"/api/widgets/instances/{widget_id}/data")
+
+    assert response.status_code == 200
+    data = response.json()
+    assert data["widget_type"] == "prometheus-metric"
+    assert data["data"]["result"]["resultType"] == "scalar"
+
+
+def test_fetch_jellyfin_widget_data_error(client):
+    response = client.post(
+        "/api/widgets/instances",
+        json={
+            "addon_id": "core",
+            "widget_type": "jellyfin",
+            "title": "Activity",
+            "config": {"machine_id": ""},
+        },
+    )
+    widget_id = response.json()["id"]
+
+    response = client.get(f"/api/widgets/instances/{widget_id}/data")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["widget_type"] == "jellyfin"
+    assert data["data"] is None
+    assert data["error"] is not None
+    assert "Jellyfin" in data["error"] or "machine" in data["error"].lower()
+
+
+def test_fetch_widget_data_not_found(client):
+    response = client.get("/api/widgets/instances/does-not-exist/data")
+    assert response.status_code == 404
+
+
+def test_fetch_widget_data_unhandled_exception_returns_500(client):
+    response = client.post(
+        "/api/widgets/instances",
+        json={
+            "addon_id": "core",
+            "widget_type": "static",
+            "title": "Note",
+            "config": {"text": "x"},
+        },
+    )
+    widget_id = response.json()["id"]
+
+    class _ExplodingAdapter:
+        source_type = "static"
+
+        async def fetch(self, config):
+            raise RuntimeError("boom")
+
+    with patch("media_library_viewer_api.routers.widgets.get_source_adapter", return_value=_ExplodingAdapter()):
+        response = client.get(f"/api/widgets/instances/{widget_id}/data")
+
+    assert response.status_code == 500
+
+
+@pytest.mark.asyncio
+async def test_static_adapter():
+    adapter = StaticWidgetSource()
+    result = await adapter.fetch({"text": "hello"})
+    assert result == {"text": "hello"}
+
+
+@pytest.mark.asyncio
+async def test_grafana_adapter():
+    adapter = GrafanaWidgetSource()
+    result = await adapter.fetch({"dashboard_uid": "overview", "panel_id": 2})
+    assert result["url"] == "http://grafana:3000/d/overview?viewPanel=2"
+
+    result = await adapter.fetch({"dashboard_uid": "overview"})
+    assert result["url"] == "http://grafana:3000/d/overview"
+
+
+@pytest.mark.asyncio
+async def test_ssh_task_adapter_timeout(tmp_path):
+    store = SettingsStore(tmp_path / "settings.sqlite")
+    store.ensure_defaults()
+
+    # Create a local machine and a simple shell task.
+    machine = store.list_machines()[0]
+    task = store.upsert_task(
+        {
+            "name": "slow-task",
+            "task_type": "shell",
+            "content": "echo hello",
+            "enabled": True,
+            "default_machine_id": machine["id"],
+        }
+    )
+
+    adapter = SshTaskWidgetSource()
+    with patch(
+        "media_library_viewer_api.widgets.sources.get_settings_store",
+        return_value=store,
+    ), patch(
+        "media_library_viewer_api.widgets.sources.asyncio.wait_for",
+        side_effect=asyncio.TimeoutError,
+    ):
+        result = await adapter.fetch({"task_id": task["id"]})
+
+    assert "error" in result
+    assert "timed out" in result["error"].lower()
+
+
+def test_source_registry_closed():
+    assert set(SOURCE_REGISTRY.keys()) == {
+        "jellyfin",
+        "backups",
+        "grafana",
+        "prometheus",
+        "ssh_task",
+        "static",
+    }

docker-compose.dev.yml

@@ -17,6 +17,8 @@ services:
       PROMETHEUS_FILE_SD_DIR: /app/backend/.cache/prometheus-file-sd
       ALERTMANAGER_URL: ${ALERTMANAGER_URL:-http://alertmanager:9093}
       ALERTMANAGER_WEBHOOK_URL: ${ALERTMANAGER_WEBHOOK_URL:-}
+      GRAFANA_URL: ${GRAFANA_URL:-http://grafana:3000}
+      PROMETHEUS_URL: ${PROMETHEUS_URL:-http://prometheus:9090}
     ports:
       - "8000:8000"
     volumes:

docker-compose.yml

@@ -28,6 +28,8 @@ services:
       PROMETHEUS_FILE_SD_DIR: ${PROMETHEUS_FILE_SD_DIR:-/app/backend/.cache/prometheus-file-sd}
       ALERTMANAGER_URL: ${ALERTMANAGER_URL:-http://alertmanager:9093}
       ALERTMANAGER_WEBHOOK_URL: ${ALERTMANAGER_WEBHOOK_URL:-}
+      GRAFANA_URL: ${GRAFANA_URL:-http://grafana:3000}
+      PROMETHEUS_URL: ${PROMETHEUS_URL:-http://prometheus:9090}
     volumes:
       - ${BACKEND_CACHE_DIR:-./backend-cache}:/app/backend/.cache
     restart: unless-stopped

docs/REQUIREMENTS.md

@@ -256,6 +256,54 @@ fully removed (web-ui-rework; see decision log 2026-06-17).
 - Job templates should remain centralized in `jobs.py` for future extension.
 - Remote job template values must be shell-quoted before execution.
 
+## Configurable Dashboard Widgets
+
+### Overview
+
+The dashboard is composed of persisted widget instances stored in the backend SQLite
+settings database. Each widget has a type, title, configuration, enabled flag, and
+sort order. The frontend renders enabled widgets in sort order and fetches data
+independently through the backend source adapters.
+
+### Widget types
+
+- **Jellyfin activity** — live sessions and idle users from a configured Jellyfin machine.
+- **Backups** — backup job summary and active alerts.
+- **Grafana link** — deep-link to a Grafana dashboard or panel (no iframe embedding).
+- **Prometheus metric** — result of a PromQL instant query.
+- **SSH task output** — output of a saved task run on a machine.
+- **Static text** — plain text or markdown note.
+
+### Security
+
+- Widget `config` may not contain credential keys such as `password`, `token`,
+  `secret`, `api_key`, `private_key`, or `passphrase`, or values that look like
+  secrets (e.g., base64 blobs, `sk-` prefixes).
+- Widgets reuse machine-level Jellyfin/SSH credentials and environment settings for
+  Grafana/Prometheus URLs; no secrets are stored in widget configuration.
+- SSH task widgets only run tasks from the saved-task registry; arbitrary commands
+  are not accepted.
+
+### Addon pages
+
+Each non-core addon gets a dedicated page at `/addons/:addonId`:
+
+- `/addons/grafana`
+- `/addons/prometheus`
+- `/addons/ssh-tasks`
+
+Unknown addons render a "not installed" alert.
+
+### API
+
+- `GET /api/widgets/sources` — list source types.
+- `GET /api/widgets/types` — list widget type metadata.
+- `GET /api/widgets/instances` — list widget instances.
+- `POST /api/widgets/instances` — create instance.
+- `PUT /api/widgets/instances/{id}` — update instance.
+- `DELETE /api/widgets/instances/{id}` — delete instance.
+- `GET /api/widgets/instances/{id}/data` — fetch widget data.
+
 ## Decision Log
 
 - 2026-06-17: Decommissioned the legacy Manage-side system-metric scraping. Removed the backend `MonitoringPoller` (SSH-ran `df` on every machine every 5 min into a local SQLite `monitoring_machine_actions` table), the entire `services/monitoring_actions.py` module, the `/api/monitoring/poller`, `/api/monitoring/machines/{id}/actions`, and `/api/monitoring/disk` endpoints, the `monitoring_machine_actions` table (DROP on startup), the three `monitoring_poll_*` / `monitoring_action_retention_days` config knobs, and the orphaned frontend `DiskSpaceCard` + `DiskSpace` type. System metrics are now owned exclusively by Prometheus + node_exporter + Grafana. Kept the Alertmanager proxy (`/alerts`, `/alertmanager-status`, `/alertmanager-webhook`), `/prometheus-targets`, `/machines`, the `node_exporter_*` machine fields, and the on-demand `disk_usage` job template.

frontend/src/App.tsx

@@ -22,6 +22,7 @@ import { FileBrowser } from "./pages/FileBrowser";
 import { Actions } from "./pages/Actions";
 import BackupsPage from "./components/BackupsPage";
 import { ObservabilityPage } from "./components/ObservabilityPage";
+import { AddonPage } from "./pages/AddonPage";
 import { getOidcConfig, isOidcConfigured, setAccessToken } from "./auth";
 import { fetchAppVersion } from "./api/client";
 import { FRONTEND_VERSION_LABEL } from "./version";
@@ -449,6 +450,7 @@ function AppInner() {
 								<Route path="/backups" element={<BackupsPage />} />
 								<Route path="/observability" element={<ObservabilityPage />} />
 								<Route path="/settings" element={<Settings />} />
+								<Route path="/addons/:addonId" element={<AddonPage />} />
 							</Route>
 						</Routes>
 					</BrowserRouter>
@@ -480,6 +482,7 @@ function AppInner() {
 							<Route path="/backups" element={<BackupsPage />} />
 							<Route path="/observability" element={<ObservabilityPage />} />
 							<Route path="/settings" element={<Settings />} />
+							<Route path="/addons/:addonId" element={<AddonPage />} />
 						</Route>
 					</Routes>
 				</BrowserRouter>

frontend/src/addons/GrafanaAddonPage.tsx

@@ -0,0 +1,37 @@
+import { ExternalLink } from "lucide-react";
+import { Button } from "@/components/ui/button";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+
+export function GrafanaAddonPage() {
+	const grafanaUrl =
+		(import.meta.env.VITE_GRAFANA_URL as string | undefined) ||
+		"http://localhost:3000";
+
+	return (
+		<div className="flex flex-col gap-4">
+			<h2 className="text-xl font-semibold">Grafana</h2>
+			<Card>
+				<CardHeader>
+					<CardTitle>Metrics & logs</CardTitle>
+				</CardHeader>
+				<CardContent className="flex flex-col gap-3">
+					<p className="text-sm text-muted-foreground">
+						Open the full Grafana instance for dashboards, metrics, and log
+						exploration.
+					</p>
+					<Button asChild>
+						<a
+							href={grafanaUrl}
+							target="_blank"
+							rel="noopener noreferrer"
+							className="inline-flex items-center"
+						>
+							Open Grafana
+							<ExternalLink className="ml-2 h-4 w-4" />
+						</a>
+					</Button>
+				</CardContent>
+			</Card>
+		</div>
+	);
+}

frontend/src/addons/PrometheusAddonPage.tsx

@@ -0,0 +1,36 @@
+import { ExternalLink } from "lucide-react";
+import { Button } from "@/components/ui/button";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+
+export function PrometheusAddonPage() {
+	const prometheusUrl =
+		(import.meta.env.VITE_PROMETHEUS_URL as string | undefined) ||
+		"http://localhost:9090";
+
+	return (
+		<div className="flex flex-col gap-4">
+			<h2 className="text-xl font-semibold">Prometheus</h2>
+			<Card>
+				<CardHeader>
+					<CardTitle>Metrics explorer</CardTitle>
+				</CardHeader>
+				<CardContent className="flex flex-col gap-3">
+					<p className="text-sm text-muted-foreground">
+						Open Prometheus to run ad-hoc PromQL queries and inspect targets.
+					</p>
+					<Button asChild>
+						<a
+							href={prometheusUrl}
+							target="_blank"
+							rel="noopener noreferrer"
+							className="inline-flex items-center"
+						>
+							Open Prometheus
+							<ExternalLink className="ml-2 h-4 w-4" />
+						</a>
+					</Button>
+				</CardContent>
+			</Card>
+		</div>
+	);
+}

frontend/src/addons/SshTasksAddonPage.tsx

@@ -0,0 +1,29 @@
+import { Terminal } from "lucide-react";
+import { Button } from "@/components/ui/button";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+import { useNavigate } from "react-router-dom";
+
+export function SshTasksAddonPage() {
+	const navigate = useNavigate();
+
+	return (
+		<div className="flex flex-col gap-4">
+			<h2 className="text-xl font-semibold">SSH tasks</h2>
+			<Card>
+				<CardHeader>
+					<CardTitle>Saved actions</CardTitle>
+				</CardHeader>
+				<CardContent className="flex flex-col gap-3">
+					<p className="text-sm text-muted-foreground">
+						Create, edit, and run saved shell or Python tasks against local or
+						remote machines.
+					</p>
+					<Button onClick={() => navigate("/actions")}>
+						<Terminal className="mr-2 h-4 w-4" />
+						Open Actions
+					</Button>
+				</CardContent>
+			</Card>
+		</div>
+	);
+}

frontend/src/addons/index.ts

@@ -0,0 +1,3 @@
+export { GrafanaAddonPage } from "./GrafanaAddonPage";
+export { PrometheusAddonPage } from "./PrometheusAddonPage";
+export { SshTasksAddonPage } from "./SshTasksAddonPage";

frontend/src/api/widgets.ts

@@ -0,0 +1,69 @@
+import type {
+	WidgetDataResponse,
+	WidgetInstance,
+	WidgetInstanceInput,
+	WidgetTypeInfo,
+} from "../types";
+
+const API_BASE = "/api";
+
+export async function fetchWidgetSources(): Promise<string[]> {
+	const res = await fetch(`${API_BASE}/widgets/sources`);
+	if (!res.ok) throw new Error("Failed to fetch widget sources");
+	return res.json();
+}
+
+export async function fetchWidgetTypes(): Promise<WidgetTypeInfo[]> {
+	const res = await fetch(`${API_BASE}/widgets/types`);
+	if (!res.ok) throw new Error("Failed to fetch widget types");
+	return res.json();
+}
+
+export async function fetchWidgetInstances(): Promise<WidgetInstance[]> {
+	const res = await fetch(`${API_BASE}/widgets/instances`);
+	if (!res.ok) throw new Error("Failed to fetch widget instances");
+	return res.json();
+}
+
+export async function createWidgetInstance(
+	input: WidgetInstanceInput,
+): Promise<WidgetInstance> {
+	const res = await fetch(`${API_BASE}/widgets/instances`, {
+		method: "POST",
+		headers: { "Content-Type": "application/json" },
+		body: JSON.stringify(input),
+	});
+	if (!res.ok) throw new Error("Failed to create widget instance");
+	return res.json();
+}
+
+export async function updateWidgetInstance(
+	input: WidgetInstanceInput,
+): Promise<WidgetInstance> {
+	if (!input.id) throw new Error("Widget ID is required for update");
+	const res = await fetch(`${API_BASE}/widgets/instances/${input.id}`, {
+		method: "PUT",
+		headers: { "Content-Type": "application/json" },
+		body: JSON.stringify(input),
+	});
+	if (!res.ok) throw new Error("Failed to update widget instance");
+	return res.json();
+}
+
+export async function deleteWidgetInstance(
+	widgetId: string,
+): Promise<{ status: string }> {
+	const res = await fetch(`${API_BASE}/widgets/instances/${widgetId}`, {
+		method: "DELETE",
+	});
+	if (!res.ok) throw new Error("Failed to delete widget instance");
+	return res.json();
+}
+
+export async function fetchWidgetData(
+	widgetId: string,
+): Promise<WidgetDataResponse> {
+	const res = await fetch(`${API_BASE}/widgets/instances/${widgetId}/data`);
+	if (!res.ok) throw new Error("Failed to fetch widget data");
+	return res.json();
+}

frontend/src/components/WidgetConfigDialog.tsx

@@ -0,0 +1,464 @@
+import { useMemo, useState } from "react";
+import {
+	Dialog,
+	DialogContent,
+	DialogHeader,
+	DialogTitle,
+} from "@/components/ui/dialog";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { Label } from "@/components/ui/label";
+import { Switch } from "@/components/ui/switch";
+import {
+	Select,
+	SelectContent,
+	SelectItem,
+	SelectTrigger,
+	SelectValue,
+} from "@/components/ui/select";
+import { Badge } from "@/components/ui/badge";
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { ChevronDown, ChevronUp, Pencil, Plus, Trash2 } from "lucide-react";
+import {
+	useDeleteWidgetInstance,
+	useSaveWidgetInstance,
+	useWidgetInstances,
+	useWidgetTypes,
+} from "../hooks/useWidgets";
+import { useMonitoringSettings, useTasks } from "../hooks/useSettings";
+import type {
+	MonitoringMachine,
+	SavedTask,
+	WidgetInstance,
+	WidgetInstanceInput,
+} from "../types";
+import {
+	getWidgetDefinition,
+	listWidgetTypes,
+	type WidgetDefinition,
+} from "../widgets/registry";
+
+interface Props {
+	open: boolean;
+	onClose: () => void;
+}
+
+function emptyDraft(widgetType: string): WidgetInstanceInput {
+	const def = getWidgetDefinition(widgetType);
+	return {
+		addon_id: def?.addonId ?? "",
+		widget_type: widgetType,
+		title: def?.name ?? "",
+		config: { ...(def?.defaultConfig ?? {}) },
+		enabled: true,
+		sort_order: 0,
+	};
+}
+
+function Field({
+	label,
+	htmlFor,
+	helper,
+	children,
+}: {
+	label: string;
+	htmlFor: string;
+	helper?: string;
+	children: React.ReactNode;
+}) {
+	return (
+		<div className="flex flex-col gap-1.5">
+			<Label htmlFor={htmlFor}>{label}</Label>
+			{children}
+			{helper ? (
+				<p className="text-xs text-muted-foreground">{helper}</p>
+			) : null}
+		</div>
+	);
+}
+
+function WidgetConfigFields({
+	definition,
+	config,
+	onChange,
+	machines,
+	tasks,
+}: {
+	definition: WidgetDefinition;
+	config: Record<string, unknown>;
+	onChange: (config: Record<string, unknown>) => void;
+	machines: MonitoringMachine[];
+	tasks: SavedTask[];
+}) {
+	return (
+		<div className="flex flex-col gap-3">
+			{definition.configFields.map((field) => {
+				const value = config[field.key] ?? "";
+
+				if (
+					definition.widgetType === "jellyfin" &&
+					field.key === "machine_id"
+				) {
+					return (
+						<Field
+							key={field.key}
+							label={field.label}
+							htmlFor={field.key}
+							helper={field.helper}
+						>
+							<Select
+								value={String(value)}
+								onValueChange={(v) => onChange({ ...config, [field.key]: v })}
+							>
+								<SelectTrigger id={field.key}>
+									<SelectValue />
+								</SelectTrigger>
+								<SelectContent>
+									<SelectItem value="">Default</SelectItem>
+									{machines
+										.filter((m) => m.enabled && m.services.includes("jellyfin"))
+										.map((m) => (
+											<SelectItem key={m.id} value={m.id}>
+												{m.name}
+											</SelectItem>
+										))}
+								</SelectContent>
+							</Select>
+						</Field>
+					);
+				}
+
+				if (definition.widgetType === "ssh-task" && field.key === "task_id") {
+					return (
+						<Field
+							key={field.key}
+							label={field.label}
+							htmlFor={field.key}
+							helper={field.helper}
+						>
+							<Select
+								value={String(value)}
+								onValueChange={(v) => onChange({ ...config, [field.key]: v })}
+							>
+								<SelectTrigger id={field.key}>
+									<SelectValue />
+								</SelectTrigger>
+								<SelectContent>
+									{tasks
+										.filter((t) => t.enabled)
+										.map((t) => (
+											<SelectItem key={t.id} value={t.id}>
+												{t.name}
+											</SelectItem>
+										))}
+								</SelectContent>
+							</Select>
+						</Field>
+					);
+				}
+
+				if (field.type === "number") {
+					return (
+						<Field
+							key={field.key}
+							label={field.label}
+							htmlFor={field.key}
+							helper={field.helper}
+						>
+							<Input
+								id={field.key}
+								type="number"
+								value={String(value)}
+								onChange={(e) =>
+									onChange({
+										...config,
+										[field.key]:
+											e.target.value === ""
+												? undefined
+												: Number(e.target.value),
+									})
+								}
+							/>
+						</Field>
+					);
+				}
+
+				return (
+					<Field
+						key={field.key}
+						label={field.label}
+						htmlFor={field.key}
+						helper={field.helper}
+					>
+						<Input
+							id={field.key}
+							value={String(value)}
+							onChange={(e) =>
+								onChange({
+									...config,
+									[field.key]: e.target.value,
+								})
+							}
+						/>
+					</Field>
+				);
+			})}
+		</div>
+	);
+}
+
+export function WidgetConfigDialog({ open, onClose }: Props) {
+	const { data: instances = [] } = useWidgetInstances();
+	const { data: types = [] } = useWidgetTypes();
+	const { data: machines = [] } = useMonitoringSettings();
+	const { data: tasks = [] } = useTasks();
+	const saveWidget = useSaveWidgetInstance();
+	const deleteWidget = useDeleteWidgetInstance();
+
+	const [draft, setDraft] = useState<WidgetInstanceInput | null>(null);
+	const [editingId, setEditingId] = useState<string | null>(null);
+
+	const registryDefinitions = useMemo(() => listWidgetTypes(), []);
+
+	const sortedInstances = useMemo(
+		() =>
+			[...instances].sort(
+				(a, b) => a.sort_order - b.sort_order || a.created_at - b.created_at,
+			),
+		[instances],
+	);
+
+	function startAdd(widgetType: string) {
+		setDraft(emptyDraft(widgetType));
+		setEditingId(null);
+	}
+
+	function startEdit(instance: WidgetInstance) {
+		setDraft({
+			id: instance.id,
+			addon_id: instance.addon_id,
+			widget_type: instance.widget_type,
+			title: instance.title,
+			config: instance.config,
+			enabled: instance.enabled,
+			sort_order: instance.sort_order,
+		});
+		setEditingId(instance.id);
+	}
+
+	function reset() {
+		setDraft(null);
+		setEditingId(null);
+	}
+
+	async function saveDraft() {
+		if (!draft) return;
+		await saveWidget.mutateAsync(draft);
+		reset();
+	}
+
+	async function toggleEnabled(instance: WidgetInstance) {
+		await saveWidget.mutateAsync({
+			...instance,
+			enabled: !instance.enabled,
+		});
+	}
+
+	async function moveInstance(index: number, direction: -1 | 1) {
+		const targetIndex = index + direction;
+		if (targetIndex < 0 || targetIndex >= sortedInstances.length) return;
+		const a = sortedInstances[index];
+		const b = sortedInstances[targetIndex];
+		await Promise.all([
+			saveWidget.mutateAsync({ ...a, sort_order: b.sort_order }),
+			saveWidget.mutateAsync({ ...b, sort_order: a.sort_order }),
+		]);
+	}
+
+	async function removeInstance(instance: WidgetInstance) {
+		await deleteWidget.mutateAsync(instance.id);
+	}
+
+	function handleClose(next: boolean) {
+		if (!next) {
+			reset();
+			onClose();
+		}
+	}
+
+	const definition = draft ? getWidgetDefinition(draft.widget_type) : undefined;
+
+	return (
+		<Dialog open={open} onOpenChange={handleClose}>
+			<DialogContent className="sm:max-w-2xl">
+				<DialogHeader>
+					<DialogTitle>
+						{draft
+							? editingId
+								? "Edit widget"
+								: "Add widget"
+							: "Dashboard widgets"}
+					</DialogTitle>
+				</DialogHeader>
+
+				{draft && definition ? (
+					<div className="flex flex-col gap-4">
+						<p className="text-sm text-muted-foreground">
+							{definition.description}
+						</p>
+						<div className="grid grid-cols-1 gap-3 sm:grid-cols-2">
+							<Field label="Title" htmlFor="widget-title">
+								<Input
+									id="widget-title"
+									value={draft.title}
+									onChange={(e) =>
+										setDraft({ ...draft, title: e.target.value })
+									}
+								/>
+							</Field>
+							<Field label="Sort order" htmlFor="widget-sort-order">
+								<Input
+									id="widget-sort-order"
+									type="number"
+									value={String(draft.sort_order)}
+									onChange={(e) =>
+										setDraft({
+											...draft,
+											sort_order:
+												e.target.value === "" ? 0 : Number(e.target.value),
+										})
+									}
+								/>
+							</Field>
+						</div>
+						<div className="flex items-center gap-2">
+							<Switch
+								id="widget-enabled"
+								checked={draft.enabled}
+								onCheckedChange={(checked) =>
+									setDraft({ ...draft, enabled: checked })
+								}
+							/>
+							<Label htmlFor="widget-enabled">Enabled</Label>
+						</div>
+						<WidgetConfigFields
+							definition={definition}
+							config={draft.config}
+							onChange={(config) => setDraft({ ...draft, config })}
+							machines={machines}
+							tasks={tasks}
+						/>
+						<div className="flex justify-end gap-2">
+							<Button variant="outline" onClick={reset}>
+								Back
+							</Button>
+							<Button onClick={saveDraft} disabled={saveWidget.isPending}>
+								Save widget
+							</Button>
+						</div>
+					</div>
+				) : (
+					<div className="flex flex-col gap-4">
+						{sortedInstances.length === 0 ? (
+							<Alert>
+								<AlertDescription>
+									No widgets yet. Add one below.
+								</AlertDescription>
+							</Alert>
+						) : (
+							<div className="flex flex-col gap-2">
+								{sortedInstances.map((instance, index) => {
+									const typeDef = getWidgetDefinition(instance.widget_type);
+									return (
+										<div
+											key={instance.id}
+											className="flex items-center gap-2 rounded border p-2"
+										>
+											<div className="flex flex-1 flex-col gap-1">
+												<div className="flex items-center gap-2">
+													<span className="font-medium">{instance.title}</span>
+													<Badge variant="outline">
+														{typeDef?.name ?? instance.widget_type}
+													</Badge>
+													{!instance.enabled ? (
+														<Badge variant="secondary">disabled</Badge>
+													) : null}
+												</div>
+											</div>
+											<div className="flex items-center gap-1">
+												<Button
+													variant="ghost"
+													size="icon"
+													className="h-8 w-8"
+													disabled={index === 0}
+													onClick={() => moveInstance(index, -1)}
+												>
+													<ChevronUp className="h-4 w-4" />
+												</Button>
+												<Button
+													variant="ghost"
+													size="icon"
+													className="h-8 w-8"
+													disabled={index === sortedInstances.length - 1}
+													onClick={() => moveInstance(index, 1)}
+												>
+													<ChevronDown className="h-4 w-4" />
+												</Button>
+												<Switch
+													checked={instance.enabled}
+													onCheckedChange={() => toggleEnabled(instance)}
+													aria-label={`Toggle ${instance.title}`}
+												/>
+												<Button
+													variant="ghost"
+													size="icon"
+													className="h-8 w-8"
+													onClick={() => startEdit(instance)}
+												>
+													<Pencil className="h-4 w-4" />
+												</Button>
+												<Button
+													variant="ghost"
+													size="icon"
+													className="h-8 w-8 text-destructive"
+													onClick={() => removeInstance(instance)}
+												>
+													<Trash2 className="h-4 w-4" />
+												</Button>
+											</div>
+										</div>
+									);
+								})}
+							</div>
+						)}
+
+						<div className="flex flex-col gap-2">
+							<p className="text-sm font-medium">Add widget</p>
+							<div className="flex flex-wrap gap-2">
+								{registryDefinitions.map((def) => (
+									<Button
+										key={def.widgetType}
+										variant="outline"
+										size="sm"
+										onClick={() => startAdd(def.widgetType)}
+									>
+										<Plus className="mr-1 h-3 w-3" />
+										{def.name}
+									</Button>
+								))}
+							</div>
+						</div>
+
+						{types.length === 0 ? (
+							<Alert>
+								<AlertDescription>
+									Widget registry is empty. Backend may not be running.
+								</AlertDescription>
+							</Alert>
+						) : null}
+					</div>
+				)}
+			</DialogContent>
+		</Dialog>
+	);
+}

frontend/src/components/WidgetInstance.tsx

@@ -0,0 +1,26 @@
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { getWidgetDefinition } from "../widgets/registry";
+import type { WidgetInstance } from "../types";
+import { SectionCard } from "./SectionCard";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+export function WidgetInstance({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	if (!def) {
+		return (
+			<SectionCard title={widget.title}>
+				<Alert>
+					<AlertDescription>
+						Unknown widget type: {widget.widget_type}
+					</AlertDescription>
+				</Alert>
+			</SectionCard>
+		);
+	}
+
+	const Component = def.component;
+	return <Component widget={widget} />;
+}

frontend/src/hooks/useWidgets.ts

@@ -0,0 +1,64 @@
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import {
+	createWidgetInstance,
+	deleteWidgetInstance,
+	fetchWidgetData,
+	fetchWidgetInstances,
+	fetchWidgetSources,
+	fetchWidgetTypes,
+	updateWidgetInstance,
+} from "../api/widgets";
+import type { WidgetInstanceInput } from "../types";
+
+export function useWidgetInstances() {
+	return useQuery({
+		queryKey: ["widgets", "instances"],
+		queryFn: fetchWidgetInstances,
+		refetchInterval: 60_000,
+	});
+}
+
+export function useWidgetData(widgetId: string, refreshInterval: number) {
+	return useQuery({
+		queryKey: ["widgets", "data", widgetId],
+		queryFn: () => fetchWidgetData(widgetId),
+		refetchInterval: refreshInterval || false,
+		enabled: !!widgetId,
+		retry: 1,
+	});
+}
+
+export function useSaveWidgetInstance() {
+	const queryClient = useQueryClient();
+	return useMutation({
+		mutationFn: (input: WidgetInstanceInput) =>
+			input.id ? updateWidgetInstance(input) : createWidgetInstance(input),
+		onSuccess: () => {
+			queryClient.invalidateQueries({ queryKey: ["widgets", "instances"] });
+		},
+	});
+}
+
+export function useDeleteWidgetInstance() {
+	const queryClient = useQueryClient();
+	return useMutation({
+		mutationFn: (widgetId: string) => deleteWidgetInstance(widgetId),
+		onSuccess: () => {
+			queryClient.invalidateQueries({ queryKey: ["widgets", "instances"] });
+		},
+	});
+}
+
+export function useWidgetSources() {
+	return useQuery({
+		queryKey: ["widgets", "sources"],
+		queryFn: fetchWidgetSources,
+	});
+}
+
+export function useWidgetTypes() {
+	return useQuery({
+		queryKey: ["widgets", "types"],
+		queryFn: fetchWidgetTypes,
+	});
+}

frontend/src/pages/AddonPage.tsx

@@ -0,0 +1,28 @@
+import { useParams } from "react-router-dom";
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import {
+	GrafanaAddonPage,
+	PrometheusAddonPage,
+	SshTasksAddonPage,
+} from "../addons";
+
+const ADDON_PAGES: Record<string, React.ComponentType> = {
+	grafana: GrafanaAddonPage,
+	prometheus: PrometheusAddonPage,
+	"ssh-tasks": SshTasksAddonPage,
+};
+
+export function AddonPage() {
+	const { addonId } = useParams<{ addonId: string }>();
+	const Page = addonId ? ADDON_PAGES[addonId] : undefined;
+
+	if (!Page) {
+		return (
+			<Alert>
+				<AlertDescription>Addon "{addonId}" is not installed.</AlertDescription>
+			</Alert>
+		);
+	}
+
+	return <Page />;
+}

frontend/src/pages/Dashboard.tsx

@@ -21,18 +21,17 @@ import {
 } from "@/components/ui/select";
 import { Switch } from "@/components/ui/switch";
 import {
-	useActivity,
 	useDashboardShortcuts,
 	useDeleteDashboardShortcut,
 	useSaveDashboardShortcut,
 } from "../hooks/useDashboard";
-import { useMonitoringSettings } from "../hooks/useSettings";
+import { useWidgetInstances } from "../hooks/useWidgets";
 import type { DashboardShortcut, DashboardShortcutInput } from "../types";
-import { NowPlaying } from "../components/NowPlaying";
 import { SectionCard } from "../components/SectionCard";
 import { ConfirmDialog } from "../components/ConfirmDialog";
 import { DialogFooter } from "../components/DialogFooter";
-import BackupDashboardWidget from "../components/BackupDashboardWidget";
+import { WidgetInstance } from "../components/WidgetInstance";
+import { WidgetConfigDialog } from "../components/WidgetConfigDialog";
 
 function emptyShortcut(): DashboardShortcutInput {
 	return {
@@ -327,19 +326,6 @@ function ShortcutCard({
 
 export function Dashboard() {
 	const navigate = useNavigate();
-	const { data: machines = [] } = useMonitoringSettings();
-	const jellyfinMachines = useMemo(
-		() =>
-			machines.filter(
-				(machine) => machine.enabled && machine.services.includes("jellyfin"),
-			),
-		[machines],
-	);
-	const [activeJellyfinMachineId, setActiveJellyfinMachineId] =
-		useState<string>("");
-	const selectedJellyfinId =
-		activeJellyfinMachineId || jellyfinMachines[0]?.id || "";
-	const { data: activity } = useActivity(selectedJellyfinId || undefined);
 	const { data: shortcuts = [] } = useDashboardShortcuts();
 	const saveShortcut = useSaveDashboardShortcut();
 	const deleteShortcut = useDeleteDashboardShortcut();
@@ -348,6 +334,16 @@ export function Dashboard() {
 		emptyShortcut(),
 	);
 	const [deleteShortcutId, setDeleteShortcutId] = useState<string | null>(null);
+	const [widgetDialogOpen, setWidgetDialogOpen] = useState(false);
+	const { data: widgetInstances = [] } = useWidgetInstances();
+
+	const visibleWidgets = useMemo(
+		() =>
+			widgetInstances
+				.filter((w) => w.enabled)
+				.sort((a, b) => a.sort_order - b.sort_order),
+		[widgetInstances],
+	);
 
 	const openCreateShortcut = () => {
 		setShortcutDraft(emptyShortcut());
@@ -382,9 +378,14 @@ export function Dashboard() {
 				title="Shortcuts"
 				description="Quick links to websites today, with room for action and user shortcuts later."
 				action={
-					<Button variant="outline" onClick={openCreateShortcut}>
-						Add shortcut
-					</Button>
+					<div className="flex gap-2">
+						<Button variant="outline" onClick={() => setWidgetDialogOpen(true)}>
+							Edit dashboard
+						</Button>
+						<Button variant="outline" onClick={openCreateShortcut}>
+							Add shortcut
+						</Button>
+					</div>
 				}
 			>
 				{shortcuts.length ? (
@@ -416,42 +417,9 @@ export function Dashboard() {
 				)}
 			</SectionCard>
 
-			<SectionCard
-				title="Jellyfin activity"
-				description="Live sessions and idle users from Jellyfin."
-				action={
-					jellyfinMachines.length > 1 ? (
-						<Select
-							value={selectedJellyfinId}
-							onValueChange={(value) => setActiveJellyfinMachineId(value)}
-						>
-							<SelectTrigger className="h-8 w-[180px] text-xs">
-								<SelectValue />
-							</SelectTrigger>
-							<SelectContent>
-								{jellyfinMachines.map((m) => (
-									<SelectItem key={m.id} value={m.id}>
-										{m.name}
-									</SelectItem>
-								))}
-							</SelectContent>
-						</Select>
-					) : jellyfinMachines.length === 1 ? (
-						<Badge variant="outline">{jellyfinMachines[0].name}</Badge>
-					) : null
-				}
-			>
-				{activity ? (
-					<NowPlaying
-						sessions={activity}
-						onSelectSession={(session) =>
-							navigate(`/users?user=${encodeURIComponent(session.user)}`)
-						}
-					/>
-				) : null}
-			</SectionCard>
-
-			<BackupDashboardWidget />
+			{visibleWidgets.map((widget) => (
+				<WidgetInstance key={widget.id} widget={widget} />
+			))}
 
 			<ShortcutDialog
 				open={shortcutDialogOpen}
@@ -473,6 +441,10 @@ export function Dashboard() {
 					setDeleteShortcutId(null);
 				}}
 			/>
+			<WidgetConfigDialog
+				open={widgetDialogOpen}
+				onClose={() => setWidgetDialogOpen(false)}
+			/>
 		</div>
 	);
 }

frontend/src/types/index.ts

@@ -443,3 +443,42 @@ export interface PrometheusTarget {
 	labels: Record<string, string>;
 	targets: string[];
 }
+
+export interface WidgetInstance {
+	id: string;
+	addon_id: string;
+	widget_type: string;
+	title: string;
+	config: Record<string, unknown>;
+	enabled: boolean;
+	sort_order: number;
+	created_at: number;
+	updated_at: number;
+}
+
+export interface WidgetInstanceInput {
+	id?: string | null;
+	addon_id: string;
+	widget_type: string;
+	title: string;
+	config: Record<string, unknown>;
+	enabled: boolean;
+	sort_order: number;
+}
+
+export interface WidgetTypeInfo {
+	addon_id: string;
+	widget_type: string;
+	name: string;
+	description: string;
+	source_type: string;
+	config_schema: Record<string, unknown>;
+}
+
+export interface WidgetDataResponse {
+	widget_id: string;
+	widget_type: string;
+	data: Record<string, unknown> | null;
+	error: string | null;
+	fetched_at: number;
+}

frontend/src/widgets/BackupsWidget.tsx

@@ -0,0 +1,66 @@
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { Badge } from "@/components/ui/badge";
+import { Skeleton } from "@/components/ui/skeleton";
+import { SectionCard } from "../components/SectionCard";
+import { useWidgetData } from "../hooks/useWidgets";
+import type { BackupDashboardSummary } from "../types/backups";
+import type { WidgetInstance } from "../types";
+import { getWidgetDefinition } from "./registry";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+export function BackupsWidget({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	const { data, isLoading } = useWidgetData(
+		widget.id,
+		def?.refreshInterval ?? 0,
+	);
+	const summary = data?.data as BackupDashboardSummary | undefined;
+
+	return (
+		<SectionCard title={widget.title} description={def?.description}>
+			{isLoading && !data ? (
+				<div className="flex flex-row flex-wrap gap-6">
+					<Skeleton className="h-10 w-20" />
+					<Skeleton className="h-10 w-20" />
+					<Skeleton className="h-10 w-20" />
+				</div>
+			) : data?.error ? (
+				<Alert variant="destructive">
+					<AlertDescription>{data.error}</AlertDescription>
+				</Alert>
+			) : summary ? (
+				<div className="flex flex-row flex-wrap gap-6">
+					<div>
+						<div className="text-2xl font-semibold">{summary.total_jobs}</div>
+						<div className="text-xs text-muted-foreground">Jobs</div>
+					</div>
+					<div>
+						<div className="text-2xl font-semibold">
+							{summary.success_rate_24h}%
+						</div>
+						<div className="text-xs text-muted-foreground">24h Success</div>
+					</div>
+					<div>
+						<div className="text-2xl font-semibold">
+							{summary.active_alerts > 0 ? (
+								<Badge variant="destructive">{summary.active_alerts}</Badge>
+							) : (
+								0
+							)}
+						</div>
+						<div className="text-xs text-muted-foreground">Alerts</div>
+					</div>
+					{summary.last_failed_at ? (
+						<div className="self-center text-xs text-destructive">
+							Last failed:{" "}
+							{new Date(summary.last_failed_at * 1000).toLocaleString()}
+						</div>
+					) : null}
+				</div>
+			) : null}
+		</SectionCard>
+	);
+}

frontend/src/widgets/GrafanaLinkWidget.tsx

@@ -0,0 +1,44 @@
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { Button } from "@/components/ui/button";
+import { Skeleton } from "@/components/ui/skeleton";
+import { ExternalLink } from "lucide-react";
+import { SectionCard } from "../components/SectionCard";
+import { useWidgetData } from "../hooks/useWidgets";
+import type { WidgetInstance } from "../types";
+import { getWidgetDefinition } from "./registry";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+export function GrafanaLinkWidget({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	const { data, isLoading } = useWidgetData(
+		widget.id,
+		def?.refreshInterval ?? 0,
+	);
+	const url = data?.data?.url as string | undefined;
+
+	return (
+		<SectionCard title={widget.title} description={def?.description}>
+			{isLoading && !data ? (
+				<Skeleton className="h-10 w-48" />
+			) : data?.error ? (
+				<Alert variant="destructive">
+					<AlertDescription>{data.error}</AlertDescription>
+				</Alert>
+			) : url ? (
+				<Button asChild>
+					<a href={url} target="_blank" rel="noopener noreferrer">
+						Open Grafana
+						<ExternalLink className="ml-2 h-4 w-4" />
+					</a>
+				</Button>
+			) : (
+				<Alert>
+					<AlertDescription>No Grafana URL configured.</AlertDescription>
+				</Alert>
+			)}
+		</SectionCard>
+	);
+}

frontend/src/widgets/JellyfinWidget.tsx

@@ -0,0 +1,40 @@
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { Skeleton } from "@/components/ui/skeleton";
+import { SessionActivityPanel } from "../components/SessionActivityPanel";
+import { SectionCard } from "../components/SectionCard";
+import { useWidgetData } from "../hooks/useWidgets";
+import type { NowPlayingSession, WidgetInstance } from "../types";
+import { getWidgetDefinition } from "./registry";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+export function JellyfinWidget({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	const { data, isLoading } = useWidgetData(
+		widget.id,
+		def?.refreshInterval ?? 0,
+	);
+	const sessions = data?.data?.sessions as NowPlayingSession[] | undefined;
+
+	return (
+		<SectionCard title={widget.title} description={def?.description}>
+			{isLoading && !data ? (
+				<div className="flex flex-col gap-2">
+					<Skeleton className="h-4 w-3/4" />
+					<Skeleton className="h-4 w-1/2" />
+				</div>
+			) : data?.error ? (
+				<Alert variant="destructive">
+					<AlertDescription>{data.error}</AlertDescription>
+				</Alert>
+			) : Array.isArray(sessions) ? (
+				<SessionActivityPanel
+					sessions={sessions}
+					emptyMessage="No recent user activity sessions right now."
+				/>
+			) : null}
+		</SectionCard>
+	);
+}

frontend/src/widgets/PrometheusMetricWidget.tsx

@@ -0,0 +1,61 @@
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { Skeleton } from "@/components/ui/skeleton";
+import { SectionCard } from "../components/SectionCard";
+import { useWidgetData } from "../hooks/useWidgets";
+import type { WidgetInstance } from "../types";
+import { getWidgetDefinition } from "./registry";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+type PromQLResult = {
+	resultType?: string;
+	result?: unknown;
+};
+
+type PromQLVectorSample = {
+	metric?: Record<string, string>;
+	value?: [number, string];
+};
+
+function formatPrometheusValue(result: PromQLResult | undefined): string {
+	if (!result) return "No data";
+	if (result.resultType === "scalar" && Array.isArray(result.result)) {
+		return String(result.result[1] ?? "No data");
+	}
+	if (
+		result.resultType === "vector" &&
+		Array.isArray(result.result) &&
+		result.result.length > 0
+	) {
+		const first = result.result[0] as PromQLVectorSample;
+		if (first.value) return String(first.value[1]);
+	}
+	return JSON.stringify(result, null, 2);
+}
+
+export function PrometheusMetricWidget({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	const { data, isLoading } = useWidgetData(
+		widget.id,
+		def?.refreshInterval ?? 0,
+	);
+	const result = data?.data?.result as PromQLResult | undefined;
+
+	return (
+		<SectionCard title={widget.title} description={def?.description}>
+			{isLoading && !data ? (
+				<Skeleton className="h-10 w-32" />
+			) : data?.error ? (
+				<Alert variant="destructive">
+					<AlertDescription>{data.error}</AlertDescription>
+				</Alert>
+			) : (
+				<pre className="whitespace-pre-wrap text-sm">
+					{formatPrometheusValue(result)}
+				</pre>
+			)}
+		</SectionCard>
+	);
+}

frontend/src/widgets/SshTaskWidget.tsx

@@ -0,0 +1,63 @@
+import { Alert, AlertDescription } from "@/components/ui/alert";
+import { Skeleton } from "@/components/ui/skeleton";
+import { SectionCard } from "../components/SectionCard";
+import { useWidgetData } from "../hooks/useWidgets";
+import type { WidgetInstance } from "../types";
+import { getWidgetDefinition } from "./registry";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+type SshTaskResult = {
+	exit_status: number;
+	stdout: string;
+	stderr: string;
+};
+
+export function SshTaskWidget({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	const { data, isLoading } = useWidgetData(
+		widget.id,
+		def?.refreshInterval ?? 0,
+	);
+	const result = data?.data as SshTaskResult | undefined;
+
+	return (
+		<SectionCard title={widget.title} description={def?.description}>
+			{isLoading && !data ? (
+				<div className="flex flex-col gap-2">
+					<Skeleton className="h-4 w-full" />
+					<Skeleton className="h-4 w-3/4" />
+				</div>
+			) : data?.error ? (
+				<Alert variant="destructive">
+					<AlertDescription>{data.error}</AlertDescription>
+				</Alert>
+			) : result ? (
+				<div className="flex flex-col gap-3">
+					<div className="text-xs text-muted-foreground">
+						Exit status:{" "}
+						<span
+							className={
+								result.exit_status === 0 ? "text-green-600" : "text-destructive"
+							}
+						>
+							{result.exit_status}
+						</span>
+					</div>
+					{result.stdout ? (
+						<pre className="max-h-64 overflow-auto rounded bg-muted p-2 text-xs">
+							{result.stdout}
+						</pre>
+					) : null}
+					{result.stderr ? (
+						<pre className="max-h-64 overflow-auto rounded bg-destructive/10 p-2 text-xs text-destructive">
+							{result.stderr}
+						</pre>
+					) : null}
+				</div>
+			) : null}
+		</SectionCard>
+	);
+}

frontend/src/widgets/StaticWidget.tsx

@@ -0,0 +1,24 @@
+import { SectionCard } from "../components/SectionCard";
+import { useWidgetData } from "../hooks/useWidgets";
+import type { WidgetInstance } from "../types";
+import { getWidgetDefinition } from "./registry";
+
+interface Props {
+	widget: WidgetInstance;
+}
+
+export function StaticWidget({ widget }: Props) {
+	const def = getWidgetDefinition(widget.widget_type);
+	const { data } = useWidgetData(widget.id, def?.refreshInterval ?? 0);
+	const text = data?.data?.text as string | undefined;
+
+	return (
+		<SectionCard title={widget.title} description={def?.description}>
+			{text ? (
+				<p className="whitespace-pre-wrap text-sm">{text}</p>
+			) : (
+				<p className="text-sm text-muted-foreground">No content configured.</p>
+			)}
+		</SectionCard>
+	);
+}

frontend/src/widgets/index.ts

@@ -0,0 +1,12 @@
+export { BackupsWidget } from "./BackupsWidget";
+export { GrafanaLinkWidget } from "./GrafanaLinkWidget";
+export { JellyfinWidget } from "./JellyfinWidget";
+export { PrometheusMetricWidget } from "./PrometheusMetricWidget";
+export { SshTaskWidget } from "./SshTaskWidget";
+export { StaticWidget } from "./StaticWidget";
+export {
+	getWidgetDefinition,
+	listWidgetTypes,
+	WIDGET_REGISTRY,
+} from "./registry";
+export type { WidgetConfigField, WidgetDefinition } from "./registry";

frontend/src/widgets/registry.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+import {
+	getWidgetDefinition,
+	listWidgetTypes,
+	WIDGET_REGISTRY,
+} from "./registry";
+
+describe("widget registry", () => {
+	it("contains exactly six Phase 1 types", () => {
+		const types = listWidgetTypes();
+		expect(types).toHaveLength(6);
+		expect(types.map((t) => t.widgetType).sort()).toEqual([
+			"backups",
+			"grafana-link",
+			"jellyfin",
+			"prometheus-metric",
+			"ssh-task",
+			"static",
+		]);
+	});
+
+	it("has refresh intervals matching the spec", () => {
+		expect(getWidgetDefinition("jellyfin")?.refreshInterval).toBe(30_000);
+		expect(getWidgetDefinition("backups")?.refreshInterval).toBe(60_000);
+		expect(getWidgetDefinition("grafana-link")?.refreshInterval).toBe(0);
+		expect(getWidgetDefinition("prometheus-metric")?.refreshInterval).toBe(
+			30_000,
+		);
+		expect(getWidgetDefinition("ssh-task")?.refreshInterval).toBe(0);
+		expect(getWidgetDefinition("static")?.refreshInterval).toBe(0);
+	});
+
+	it("defines required metadata for every widget", () => {
+		for (const def of Object.values(WIDGET_REGISTRY)) {
+			expect(def.widgetType).toBeTruthy();
+			expect(def.addonId).toBeTruthy();
+			expect(def.name).toBeTruthy();
+			expect(def.sourceType).toBeTruthy();
+			expect(def.component).toBeDefined();
+		}
+	});
+});

frontend/src/widgets/registry.ts

@@ -0,0 +1,122 @@
+import type { ComponentType } from "react";
+import type { WidgetInstance } from "../types";
+import { BackupsWidget } from "./BackupsWidget";
+import { GrafanaLinkWidget } from "./GrafanaLinkWidget";
+import { JellyfinWidget } from "./JellyfinWidget";
+import { PrometheusMetricWidget } from "./PrometheusMetricWidget";
+import { SshTaskWidget } from "./SshTaskWidget";
+import { StaticWidget } from "./StaticWidget";
+
+export interface WidgetConfigField {
+	key: string;
+	label: string;
+	type: "string" | "select" | "boolean" | "number";
+	options?: { label: string; value: string }[];
+	helper?: string;
+}
+
+export interface WidgetDefinition {
+	widgetType: string;
+	addonId: string;
+	name: string;
+	description: string;
+	sourceType: string;
+	refreshInterval: number;
+	defaultConfig: Record<string, unknown>;
+	configFields: WidgetConfigField[];
+	component: ComponentType<{ widget: WidgetInstance }>;
+}
+
+export const WIDGET_REGISTRY: Record<string, WidgetDefinition> = {
+	jellyfin: {
+		widgetType: "jellyfin",
+		addonId: "core",
+		name: "Jellyfin activity",
+		description: "Live sessions and idle users from a Jellyfin server.",
+		sourceType: "jellyfin",
+		refreshInterval: 30_000,
+		defaultConfig: { machine_id: "" },
+		configFields: [
+			{
+				key: "machine_id",
+				label: "Machine ID",
+				type: "string",
+				helper: "Jellyfin machine id (empty = default)",
+			},
+		],
+		component: JellyfinWidget,
+	},
+	backups: {
+		widgetType: "backups",
+		addonId: "backups",
+		name: "Backups",
+		description: "Backup job summary and active alerts.",
+		sourceType: "backups",
+		refreshInterval: 60_000,
+		defaultConfig: {},
+		configFields: [],
+		component: BackupsWidget,
+	},
+	"grafana-link": {
+		widgetType: "grafana-link",
+		addonId: "grafana",
+		name: "Grafana link",
+		description: "Deep-link to a Grafana dashboard or panel.",
+		sourceType: "grafana",
+		refreshInterval: 0,
+		defaultConfig: { dashboard_uid: "" },
+		configFields: [
+			{ key: "dashboard_uid", label: "Dashboard UID", type: "string" },
+			{
+				key: "panel_id",
+				label: "Panel ID",
+				type: "number",
+				helper: "Optional",
+			},
+		],
+		component: GrafanaLinkWidget,
+	},
+	"prometheus-metric": {
+		widgetType: "prometheus-metric",
+		addonId: "prometheus",
+		name: "Prometheus metric",
+		description: "Instant query result rendered as a metric.",
+		sourceType: "prometheus",
+		refreshInterval: 30_000,
+		defaultConfig: { promql: "" },
+		configFields: [{ key: "promql", label: "PromQL query", type: "string" }],
+		component: PrometheusMetricWidget,
+	},
+	"ssh-task": {
+		widgetType: "ssh-task",
+		addonId: "ssh-tasks",
+		name: "SSH task output",
+		description: "Output of a saved task run on a machine.",
+		sourceType: "ssh_task",
+		refreshInterval: 0,
+		defaultConfig: { task_id: "" },
+		configFields: [{ key: "task_id", label: "Saved task ID", type: "string" }],
+		component: SshTaskWidget,
+	},
+	static: {
+		widgetType: "static",
+		addonId: "core",
+		name: "Static text",
+		description: "Plain text or markdown note.",
+		sourceType: "static",
+		refreshInterval: 0,
+		defaultConfig: { text: "" },
+		configFields: [{ key: "text", label: "Text", type: "string" }],
+		component: StaticWidget,
+	},
+};
+
+export function getWidgetDefinition(
+	widgetType: string,
+): WidgetDefinition | undefined {
+	return WIDGET_REGISTRY[widgetType];
+}
+
+export function listWidgetTypes(): WidgetDefinition[] {
+	return Object.values(WIDGET_REGISTRY);
+}

openspec/changes/configurable-dashboard-widgets/apply-progress.md

@@ -51,11 +51,145 @@ Focused widget test output: `12 passed`.
 - None significant for Slice 1. The implementation follows the design's backend CRUD layout.
 - Used `HTTP_422_UNPROCESSABLE_CONTENT` instead of the deprecated `HTTP_422_UNPROCESSABLE_ENTITY`.
 
+## Completed tasks (Slice 2)
+
+All Slice 2 tasks are marked `- [x]` in `tasks.md`:
+
+- [x] 2.1 Add observability URL settings (`grafana_url`, `prometheus_url`)
+- [x] 2.2 Create source adapters (`jellyfin`, `backups`, `grafana`, `prometheus`, `ssh_task`, `static`)
+- [x] 2.3 Add per-widget data endpoint (`GET /api/widgets/instances/{id}/data`)
+- [x] 2.4 Extract shared backup/Jellyfin dashboard helpers into `domain/dashboard.py`
+- [x] 2.5 Add adapter + data endpoint tests
+
+## Files changed (Slice 2)
+
+### New files
+
+- `backend/src/media_library_viewer_api/widgets/sources.py` — `WidgetSource` protocol and six source adapters.
+- `backend/src/media_library_viewer_api/domain/dashboard.py` — Shared dashboard helpers (`_map_sessions_to_activity_rows`, `build_backup_dashboard_summary`).
+
+### Modified files
+
+- `backend/src/media_library_viewer_api/config.py` — Added `grafana_url` and `prometheus_url` settings.
+- `backend/src/media_library_viewer_api/routers/widgets.py` — Added `GET /api/widgets/instances/{id}/data`.
+- `backend/src/media_library_viewer_api/routers/dashboard.py` — Delegated to shared `domain/dashboard.py` helpers.
+- `backend/tests/test_widgets.py` — Added adapter and data endpoint tests.
+- `docker-compose.yml`, `docker-compose.dev.yml`, `.env.example` — Wired `GRAFANA_URL` and `PROMETHEUS_URL` for the new adapters.
+
+## Verification (Slice 2)
+
+```bash
+cd backend
+.venv/bin/python -m ruff check .              # All checks passed
+PYTHONPATH=src .venv/bin/python -m pytest     # 200 passed, 2 warnings
+cd ../frontend
+npm run lint                                  # 2 pre-existing warnings, 0 errors
+npm run build                                 # Built successfully
+```
+
+Focused widget test output: `27 passed`.
+
+## Deviations from design (Slice 2)
+
+- Adapters currently call `get_settings_store()` internally for `backups`/`ssh_task` sources. The router-level endpoint uses FastAPI DI, but adapter unit tests patch `get_settings_store` to inject a test store. A future refactor can pass `store` and `settings` explicitly into `adapter.fetch()` for cleaner testability.
+
+## Completed tasks (Slice 3)
+
+All Slice 3 tasks are marked `- [x]` in `tasks.md`:
+
+- [x] 3.1 Add TypeScript widget interfaces (`WidgetInstance`, `WidgetInstanceInput`, `WidgetTypeInfo`, `WidgetDataResponse`)
+- [x] 3.2 Create widget API client (`frontend/src/api/widgets.ts`)
+- [x] 3.3 Create widget TanStack Query hooks (`frontend/src/hooks/useWidgets.ts`)
+- [x] 3.4 Create frontend widget registry (`frontend/src/widgets/registry.ts`)
+- [x] 3.5 Implement six widget presentational components (`frontend/src/widgets/*.tsx`)
+- [x] 3.6 Add frontend registry unit test (`frontend/src/widgets/registry.test.ts`)
+
+## Files changed (Slice 3)
+
+### New files
+
+- `frontend/src/api/widgets.ts` — API functions for widget CRUD, registry metadata, and per-widget data.
+- `frontend/src/hooks/useWidgets.ts` — TanStack Query hooks for instances, data, sources, types, and mutations.
+- `frontend/src/widgets/registry.ts` — Closed frontend registry with metadata, refresh intervals, and config fields.
+- `frontend/src/widgets/JellyfinWidget.tsx` — Renders Jellyfin session activity.
+- `frontend/src/widgets/BackupsWidget.tsx` — Renders backup dashboard summary.
+- `frontend/src/widgets/GrafanaLinkWidget.tsx` — Renders a deep-link to Grafana (no iframe).
+- `frontend/src/widgets/PrometheusMetricWidget.tsx` — Renders PromQL instant query result.
+- `frontend/src/widgets/SshTaskWidget.tsx` — Renders saved SSH task output.
+- `frontend/src/widgets/StaticWidget.tsx` — Renders static text.
+- `frontend/src/widgets/index.ts` — Barrel exports.
+- `frontend/src/widgets/registry.test.ts` — Vitest unit tests for registry metadata.
+
+### Modified files
+
+- `frontend/src/types/index.ts` — Added widget TypeScript interfaces.
+
+## Verification (Slice 3)
+
+```bash
+cd backend
+.venv/bin/python -m ruff check .              # All checks passed
+PYTHONPATH=src .venv/bin/python -m pytest     # 200 passed, 2 warnings
+cd ../frontend
+npm run lint                                  # 2 pre-existing warnings, 0 errors
+npm run build                                 # Built successfully
+npm run test -- src/widgets/registry.test.ts  # 3 passed
+```
+
+## Deviations from design (Slice 3)
+
+- Registry unit test is colocated at `frontend/src/widgets/registry.test.ts` and runs with Vitest, matching the project's existing `npm run test` setup, instead of `frontend/tests/widgets.test.mjs`.
+- `JellyfinWidget` uses `SessionActivityPanel` directly because `NowPlaying` does not expose an `emptyMessage` prop.
+
+## Completed tasks (Slice 4)
+
+All Slice 4 tasks are marked `- [x]` in `tasks.md`:
+
+- [x] 4.1 Refactor `Dashboard.tsx` to render enabled widget instances in sort order
+- [x] 4.2 Create `WidgetInstance` renderer component
+- [x] 4.3 Create `WidgetConfigDialog` for add/edit/reorder/delete widgets
+- [x] 4.4 Create addon pages (`AddonPage`, `GrafanaAddonPage`, `PrometheusAddonPage`, `SshTasksAddonPage`)
+- [x] 4.5 Register `/addons/:addonId` route in `App.tsx`
+- [x] 4.6 Update `docs/REQUIREMENTS.md` with widget system documentation
+
+## Files changed (Slice 4)
+
+### New files
+
+- `frontend/src/components/WidgetInstance.tsx` — Renders a widget instance by looking up its definition and dispatching to the registered component.
+- `frontend/src/components/WidgetConfigDialog.tsx` — Dashboard widget configuration UI: list, add, edit, delete, reorder, enable/disable.
+- `frontend/src/pages/AddonPage.tsx` — Route mapper for `/addons/:addonId`.
+- `frontend/src/addons/GrafanaAddonPage.tsx` — Grafana addon landing page (deep-link only).
+- `frontend/src/addons/PrometheusAddonPage.tsx` — Prometheus addon landing page.
+- `frontend/src/addons/SshTasksAddonPage.tsx` — SSH tasks addon landing page.
+- `frontend/src/addons/index.ts` — Barrel exports.
+
+### Modified files
+
+- `frontend/src/pages/Dashboard.tsx` — Replaced hard-coded Jellyfin/Backups sections with widget instance loop; kept Shortcuts section; added "Edit dashboard" button.
+- `frontend/src/App.tsx` — Registered `/addons/:addonId` route in both OIDC and non-OIDC route trees.
+- `docs/REQUIREMENTS.md` — Added Configurable Dashboard Widgets section.
+
+## Verification (Slice 4)
+
+```bash
+cd backend
+.venv/bin/python -m ruff check .              # All checks passed
+PYTHONPATH=src .venv/bin/python -m pytest     # 200 passed, 2 warnings
+cd ../frontend
+npm run lint                                  # 2 pre-existing warnings, 0 errors
+npm run build                                 # Built successfully
+npm run test -- src/widgets/registry.test.ts  # 3 passed
+```
+
+## Deviations from design (Slice 4)
+
+- The "Edit dashboard" button lives in the Shortcuts section action area for now. A future UI pass can move it to a dedicated dashboard header.
+- Machine/task selectors in the config dialog filter to enabled Jellyfin machines / enabled tasks, which is slightly stricter than the design's generic string field.
+
 ## Remaining work
 
-- Slice 2: Backend source adapters + `GET /api/widgets/instances/{id}/data`
-- Slice 3: Frontend types/API/hooks/registry/components
-- Slice 4: Dashboard loop + configuration UI + addon pages
+- Phase 1 widget system is complete. Future work could include widget grid layout, drag-and-drop reorder, richer Prometheus visualizations, or migrating shortcuts into the widget system.
 
 ## PR boundary