docs: update presentation slides

README.md

@@ -1,4 +1,4 @@
-# Minimal Senior-Level Job Queue
+# Job Queue
 
 This is a deliberately small PostgreSQL-backed job queue for the interview assignment.
 
@@ -14,6 +14,63 @@ The important parts are:
 - idempotent job creation
 - demo UI with job state and event polling
 
+## Architecture
+
+![prompt for generating an svg image for a minimal PostgreSQL-backed job queue architecture showing React UI talking to Django API, Django API using PostgreSQL, and a separate Django worker process with N configured threads claiming jobs from PostgreSQL with SKIP LOCKED; use clean interview-project style, simple labeled boxes, directional arrows, and callouts for two tables jobs and job_events](assets/images/project-architecture.png)
+
+
+There is no queue table and no worker table. Workers are ephemeral process threads with generated ids. The queue is internal and ordered by:
+
+```text
+priority DESC, available_at ASC, created_at ASC, id ASC
+```
+
+## Statuses
+
+![prompt for generating an svg image for the job status state machine with four states queued, running, succeeded, failed; arrows queued to running, running to succeeded, running to queued for retry after failure or timeout, running to failed when attempts are exhausted, and failed to queued for manual retry; use clear color coding and small labels on each transition](assets/images/job-status-state-machine.png)
+
+The database also validates row shape:
+
+- queued jobs cannot have locks or finish timestamps
+- running jobs must have a lock owner and lease deadline
+- terminal jobs must have a finish timestamp and no lock
+
+## At-Least-Once Execution
+
+![prompt for generating an svg image for at-least-once job execution failure recovery showing worker A claims attempt 1, worker A crashes or lease expires, cleanup requeues the job, worker B claims attempt 2, and stale worker A cannot complete attempt 1 because ownership no longer matches; use a horizontal timeline with worker lanes and database state callouts](assets/images/at-least-once-lease-recovery.png)
+
+This queue provides at-least-once execution, not exactly-once execution.
+
+A worker can perform an external side effect and crash before marking a job succeeded. The lease will expire and the job can run again. Real handlers should therefore be idempotent.
+
+## Why PostgreSQL
+
+The assignment requires PostgreSQL, and PostgreSQL gives a compact solution for safe concurrent claiming through `SELECT ... FOR UPDATE SKIP LOCKED`. This keeps the implementation transactional, inspectable, and easy to demo.
+
+For a high-throughput distributed production queue, Redis-backed systems such as BullMQ or Sidekiq-style designs are common. That is documented as the next architecture, not implemented here.
+
+## Assumptions And Interview Simplifications
+
+This project is intentionally scoped as an internal single-queue system, not a multi-tenant queue platform. There is no queue CRUD, queue table, or dynamic routing model because the assignment focuses on safe claim semantics and deterministic job state.
+
+PostgreSQL is used because the assignment requires it and because it makes transactional state easy to inspect during a demo. Redis, BullMQ, Sidekiq-style designs, or a dedicated broker would be better for very high throughput or broader distributed queue use cases.
+
+The system provides at-least-once execution, not exactly-once execution. Handlers that perform external side effects must be idempotent because a worker can crash after the side effect and before marking the job succeeded.
+
+The UI is demo and observability oriented. It shows queue pressure, job state, retries, leases, and event logs, but it is not a full production operator console.
+
+Authentication and authorization are intentionally omitted from the public API for interview simplicity. A production deployment would protect all write endpoints and usually restrict operator actions by role.
+
+## Production Follow-Ups
+
+- Add authentication, authorization, and role-based permissions.
+- Add metrics, alerting, and dashboards for queue depth, age, throughput, failures, and retry rate.
+- Add event retention, archival, or partitioning so `JobEvent` does not grow forever.
+- Add rate limits, producer quotas, and backpressure controls.
+- Add cancellation or cooperative stop support for jobs.
+- Add dead-letter metadata or a dead-letter inspection view.
+- Consider Redis or a dedicated broker if throughput or cross-service distribution becomes the main requirement.
+
 ## Run
 
 ```powershell
@@ -60,52 +117,6 @@ docker compose up -d --build worker
 docker compose logs -f worker
 ```
 
-## Architecture
-
-```text
-React UI
-   |
-Django API  ---- PostgreSQL
-   |
-Django worker process
-   |
-N worker threads from env
-```
-
-There is no queue table and no worker table. Workers are ephemeral process threads with generated ids. The queue is internal and ordered by:
-
-```text
-priority DESC, available_at ASC, created_at ASC, id ASC
-```
-
-## Statuses
-
-```text
-queued -> running
-running -> succeeded
-running -> queued      retry after failure or timeout
-running -> failed      attempts exhausted
-failed  -> queued      manual retry
-```
-
-The database also validates row shape:
-
-- queued jobs cannot have locks or finish timestamps
-- running jobs must have a lock owner and lease deadline
-- terminal jobs must have a finish timestamp and no lock
-
-## At-Least-Once Execution
-
-This queue provides at-least-once execution, not exactly-once execution.
-
-A worker can perform an external side effect and crash before marking a job succeeded. The lease will expire and the job can run again. Real handlers should therefore be idempotent.
-
-## Why PostgreSQL
-
-The assignment requires PostgreSQL, and PostgreSQL gives a compact solution for safe concurrent claiming through `SELECT ... FOR UPDATE SKIP LOCKED`. This keeps the implementation transactional, inspectable, and easy to demo.
-
-For a high-throughput distributed production queue, Redis-backed systems such as BullMQ or Sidekiq-style designs are common. That is documented as the next architecture, not implemented here.
-
 ## Useful Commands
 
 Run backend tests locally with SQLite fallback:
@@ -122,6 +133,13 @@ $env:TEST_DATABASE_ENGINE="sqlite"
 python -m pytest
 ```
 
+Run pytest with coverage:
+
+```powershell
+$env:TEST_DATABASE_ENGINE="sqlite"
+python -m pytest --cov --cov-report=term-missing
+```
+
 Run worker locally:
 
 ```powershell

backend/.env.sample

@@ -1,4 +1,6 @@
 DEBUG=true
+ENABLE_DJANGO_DEBUG_TOOLBAR=true
+DJANGO_INTERNAL_IPS=127.0.0.1,localhost,host.docker.internal
 DJANGO_SECRET_KEY=change-me
 DJANGO_ALLOWED_HOSTS=localhost,127.0.0.1,0.0.0.0
 DJANGO_CORS_ALLOWED_ORIGINS=http://localhost:5173,http://127.0.0.1:5173

backend/config/settings.py

@@ -10,6 +10,9 @@ BASE_DIR = Path(__file__).resolve().parent.parent
 SECRET_KEY = os.getenv("DJANGO_SECRET_KEY", "django-insecure-job-queue-local-dev-key")
 DEBUG = os.getenv("DEBUG", "true").lower() in {"1", "true", "yes"}
 ALLOWED_HOSTS = [host.strip() for host in os.getenv("DJANGO_ALLOWED_HOSTS", "localhost,127.0.0.1,0.0.0.0").split(",")]
+ENABLE_DJANGO_DEBUG_TOOLBAR = (
+    DEBUG and os.getenv("ENABLE_DJANGO_DEBUG_TOOLBAR", "true").lower() in {"1", "true", "yes"}
+)
 
 INSTALLED_APPS = [
     "unfold",
@@ -25,6 +28,9 @@ INSTALLED_APPS = [
     "jobs",
 ]
 
+if ENABLE_DJANGO_DEBUG_TOOLBAR:
+    INSTALLED_APPS.append("debug_toolbar")
+
 MIDDLEWARE = [
     "django.middleware.security.SecurityMiddleware",
     "corsheaders.middleware.CorsMiddleware",
@@ -36,6 +42,9 @@ MIDDLEWARE = [
     "django.middleware.clickjacking.XFrameOptionsMiddleware",
 ]
 
+if ENABLE_DJANGO_DEBUG_TOOLBAR:
+    MIDDLEWARE.insert(2, "debug_toolbar.middleware.DebugToolbarMiddleware")
+
 ROOT_URLCONF = "config.urls"
 
 TEMPLATES = [
@@ -120,6 +129,21 @@ UNFOLD = {
     "SITE_SUBHEADER": "Jobs, attempts, leases, and events",
 }
 
+INTERNAL_IPS = [
+    ip.strip()
+    for ip in os.getenv("DJANGO_INTERNAL_IPS", "127.0.0.1,localhost,host.docker.internal").split(",")
+    if ip.strip()
+]
+
+
+def show_debug_toolbar(_request):
+    return ENABLE_DJANGO_DEBUG_TOOLBAR
+
+
+DEBUG_TOOLBAR_CONFIG = {
+    "SHOW_TOOLBAR_CALLBACK": show_debug_toolbar,
+}
+
 JOB_WORKER_THREADS = int(os.getenv("JOB_WORKER_THREADS", "4"))
 JOB_WORKER_POLL_INTERVAL_MS = int(os.getenv("JOB_WORKER_POLL_INTERVAL_MS", "500"))
 JOB_WORKER_LEASE_SECONDS = int(os.getenv("JOB_WORKER_LEASE_SECONDS", "30"))

backend/config/urls.py

@@ -1,3 +1,4 @@
+from django.conf import settings
 from django.contrib import admin
 from django.urls import include, path
 from drf_spectacular.views import SpectacularAPIView, SpectacularSwaggerView
@@ -31,3 +32,6 @@ urlpatterns = [
     path("api/config/", ConfigAPIView.as_view(), name="config"),
     path("api/", include("jobs.urls")),
 ]
+
+if settings.ENABLE_DJANGO_DEBUG_TOOLBAR:
+    urlpatterns.append(path("__debug__/", include("debug_toolbar.urls")))

backend/jobs/tests/test_api.py

@@ -6,6 +6,36 @@ from rest_framework.test import APIClient
 from jobs.services import create_job
 
 
+@pytest.mark.django_db
+def test_jobs_use_limit_offset_pagination():
+    create_job(job_type="demo.success")
+    create_job(job_type="demo.fail")
+    create_job(job_type="demo.slow")
+
+    response = APIClient().get("/api/jobs/?limit=2")
+
+    assert response.status_code == 200
+    body = response.json()
+    assert body["count"] == 3
+    assert body["next"] is not None
+    assert body["previous"] is None
+    assert len(body["results"]) == 2
+
+
+@pytest.mark.django_db
+def test_jobs_pagination_supports_status_and_type_filters():
+    create_job(job_type="demo.success")
+    create_job(job_type="demo.fail")
+    create_job(job_type="demo.slow")
+
+    response = APIClient().get("/api/jobs/?status=queued&type=success&limit=10")
+
+    assert response.status_code == 200
+    body = response.json()
+    assert body["count"] == 1
+    assert body["results"][0]["type"] == "demo.success"
+
+
 @pytest.mark.django_db
 def test_global_events_use_cursor_pagination():
     create_job(job_type="demo.success")

backend/jobs/views.py

@@ -1,7 +1,7 @@
 from django.db import connection
 from rest_framework import generics, status
 from rest_framework.exceptions import NotFound, ValidationError
-from rest_framework.pagination import CursorPagination
+from rest_framework.pagination import CursorPagination, LimitOffsetPagination
 from rest_framework.response import Response
 from rest_framework.views import APIView
 
@@ -17,6 +17,11 @@ class JobEventCursorPagination(CursorPagination):
     ordering = "-id"
 
 
+class JobLimitOffsetPagination(LimitOffsetPagination):
+    default_limit = 25
+    max_limit = 100
+
+
 class HealthAPIView(APIView):
     def get(self, request):
         try:
@@ -35,9 +40,15 @@ class JobListCreateAPIView(APIView):
     def get(self, request):
         queryset = Job.objects.order_by("-created_at")
         status_filter = request.query_params.get("status")
+        type_filter = request.query_params.get("type")
         if status_filter:
             queryset = queryset.filter(status=status_filter)
-        return Response(JobSerializer(queryset, many=True).data)
+        if type_filter:
+            queryset = queryset.filter(type__icontains=type_filter)
+
+        paginator = JobLimitOffsetPagination()
+        page = paginator.paginate_queryset(queryset, request, view=self)
+        return paginator.get_paginated_response(JobSerializer(page, many=True).data)
 
     def post(self, request):
         serializer = JobCreateSerializer(data=request.data)

backend/pyproject.toml

@@ -9,3 +9,25 @@ select = ["E", "W", "F", "I", "B", "C4", "UP", "DJ", "SIM"]
 "jobs/models.py" = ["DJ001"]
 "jobs/migrations/*.py" = ["E501"]
 "jobs/tests/*.py" = ["DJ001"]
+
+[tool.coverage.run]
+branch = true
+source = ["config", "jobs"]
+omit = [
+    "config/asgi.py",
+    "config/wsgi.py",
+    "jobs/management/*",
+    "*/migrations/*",
+    "*/tests/*",
+    "manage.py",
+]
+
+[tool.coverage.report]
+show_missing = true
+skip_covered = true
+fail_under = 60
+exclude_lines = [
+    "pragma: no cover",
+    "if __name__ == .__main__.:",
+    "raise NotImplementedError",
+]

backend/requirements.txt

@@ -5,6 +5,8 @@ drf-spectacular>=0.28,<0.29
 python-dotenv>=1.1,<2.0
 psycopg[binary]>=3.2,<4.0
 django-unfold>=0.76,<1.0
+django-debug-toolbar>=5.0,<6.0
 pytest>=8.0,<9.0
 pytest-django>=4.9,<5.0
+pytest-cov>=6.0,<7.0
 ruff>=0.15,<0.16

docker-compose.yml

@@ -22,6 +22,7 @@ services:
     command: sh -c "python manage.py migrate && python manage.py runserver 0.0.0.0:8000"
     environment:
       DEBUG: "true"
+      ENABLE_DJANGO_DEBUG_TOOLBAR: "true"
       DJANGO_ALLOWED_HOSTS: localhost,127.0.0.1,0.0.0.0
       DJANGO_CORS_ALLOWED_ORIGINS: http://localhost:5173,http://127.0.0.1:5173
       POSTGRES_DB: ${POSTGRES_DB:-job_queue}

frontend/README.md

@@ -2,6 +2,8 @@
 
 Vite React demo UI for the minimal job queue.
 
+![prompt for generating an svg image for the React frontend information architecture of a job queue demo UI with four routes: dashboard, jobs page, job detail page, and global events page; show shared AppLayout with topbar/sidebar, API client calling Django REST endpoints, and visual panels for stats, job table, detail timeline, and terminal-style event log; use clean product UI diagram style](../assets/images/frontend/ui-architecture.png)
+
 It reuses the visual style from the previous advanced frontend, but only keeps:
 
 - dashboard
@@ -11,11 +13,15 @@ It reuses the visual style from the previous advanced frontend, but only keeps:
 
 The UI polls:
 
+![prompt for generating an svg image for frontend polling and pagination data flow: dashboard polls jobs stats and recent events every 2 seconds, job detail polls job and job events every 1 second, events page fetches first cursor page then loads older pages on terminal scroll, jobs page uses limit-offset pagination with page size and page number; show React pages on left and API endpoints on right with interval labels](../assets/images/frontend/data-flow.png)
+
 - jobs and stats every 2 seconds
 - events every 1 second
 
 No WebSockets are used.
 
+![prompt for generating an svg image for a terminal-style event log UI component with dark console background, colored rows by event type, cursor-paginated first page, older events loaded only when scrolling inside the terminal, and custom theme-aware scrollbar; include labels for live polling, de-duplication, and infinite scroll boundary](../assets/images/frontend/terminal-event-feed.png)
+
 ## Run
 
 ```powershell

frontend/src/api.ts

@@ -1,4 +1,4 @@
-import type { CursorPage, Health, Job, JobEvent, JobStats } from "./types";
+import type { CursorPage, Health, Job, JobEvent, JobStats, LimitOffsetPage } from "./types";
 
 const API_BASE_URL = import.meta.env.VITE_API_BASE_URL ?? "http://localhost:8000/api";
 
@@ -31,9 +31,24 @@ function normalizeCursorPage<T>(value: CursorPage<T> | T[]): CursorPage<T> {
   return value;
 }
 
+function normalizeLimitOffsetPage<T>(value: LimitOffsetPage<T> | T[]): LimitOffsetPage<T> {
+  if (Array.isArray(value)) {
+    return { count: value.length, next: null, previous: null, results: value };
+  }
+  return value;
+}
+
 export const api = {
   health: () => request<Health>("/health/"),
-  listJobs: () => request<Job[]>("/jobs/"),
+  listJobs: () => api.listJobsPage({ limit: 100 }).then((page) => page.results),
+  listJobsPage: (filters: { limit?: number; offset?: number; status?: string; type?: string } = {}) => {
+    const params = new URLSearchParams();
+    Object.entries(filters).forEach(([key, value]) => {
+      if (value !== undefined && value !== null && value !== "") params.set(key, String(value));
+    });
+    const query = params.toString();
+    return request<LimitOffsetPage<Job> | Job[]>(`/jobs/${query ? `?${query}` : ""}`).then(normalizeLimitOffsetPage);
+  },
   getJob: (jobId: string) => request<Job>(`/jobs/${jobId}/`),
   createJob: (body: CreateJobBody) => request<Job>("/jobs/", { method: "POST", body: JSON.stringify(body) }),
   retryJob: (jobId: string) => request<Job>(`/jobs/${jobId}/retry/`, { method: "POST" }),

frontend/src/layout/AppLayout.tsx

@@ -26,7 +26,6 @@ export function AppLayout() {
 
   function handleThemeToggle() {
     toggleTheme();
-    toast.success(theme === "dark" ? "Light mode enabled." : "Dark mode enabled.");
   }
 
   return (

frontend/src/pages/DashboardPage.tsx

@@ -31,7 +31,9 @@ function BarMetric({ label, value, max, tone = "neutral" }: { label: string; val
   );
 }
 
-function MiniHistogram({ data }: { data: Array<{ label: string; value: number; tone: string }> }) {
+type ChartPoint = { label: string; value: number; tone: string };
+
+function MiniHistogram({ data }: { data: ChartPoint[] }) {
   const max = Math.max(...data.map((item) => item.value), 1);
   return (
     <div className="histogram" aria-label="histogram">
@@ -51,6 +53,18 @@ function MiniHistogram({ data }: { data: Array<{ label: string; value: number; t
   );
 }
 
+function StatusStack({ data }: { data: ChartPoint[] }) {
+  const total = data.reduce((sum, item) => sum + item.value, 0);
+  return (
+    <div className="status-stack" aria-label="status distribution">
+      {data.map((item) => {
+        const width = total > 0 ? Math.max(6, Math.round((item.value / total) * 100)) : 25;
+        return <i className={item.tone} key={item.label} style={{ width: `${width}%` }} title={`${item.label}: ${item.value}`} />;
+      })}
+    </div>
+  );
+}
+
 export function DashboardPage() {
   const [jobs, setJobs] = useState<Job[]>([]);
   const [events, setEvents] = useState<JobEvent[]>([]);
@@ -110,6 +124,11 @@ export function DashboardPage() {
       .map(([type, value]) => ({ label: eventTitle(type), value, tone: type.includes("fail") ? "failed" : type.includes("success") ? "succeeded" : "running" }));
   }, [events]);
   const maxPressure = Math.max(...pressureData.map((item) => item.value), 1);
+  const activePressure = stats.by_status.queued + stats.by_status.running + stats.retries_pending + stats.overdue_running;
+  const completionRate = recentJobs.length
+    ? Math.round((recentJobs.filter((job) => job.status === "succeeded").length / recentJobs.length) * 100)
+    : 0;
+  const topEvent = eventData.at(0);
 
   return (
     <div className="page">
@@ -131,7 +150,7 @@ export function DashboardPage() {
       </section>
 
       <section className="dashboard-grid">
-        <section className="panel">
+        <section className="panel chart-panel">
           <div className="section-title">
             <h3>Recent Jobs</h3>
             <Link className="secondary-button" to="/jobs">
@@ -140,6 +159,11 @@ export function DashboardPage() {
           </div>
           {recentJobs.length ? (
             <>
+              <div className="chart-summary-row">
+                <span>{recentJobs.length} latest jobs</span>
+                <strong>{completionRate}% succeeded</strong>
+              </div>
+              <StatusStack data={recentJobStatusData} />
               <MiniHistogram data={recentJobStatusData} />
               <div className="job-tick-chart" aria-label="latest jobs">
                 {recentJobs.slice(0, 16).map((job) => (
@@ -152,11 +176,15 @@ export function DashboardPage() {
           )}
         </section>
 
-        <section className="panel">
+        <section className="panel chart-panel">
           <div className="section-title">
             <h3>Queue Pressure</h3>
             <Clock3 size={16} />
           </div>
+          <div className="chart-summary-row">
+            <span>Active pressure</span>
+            <strong>{activePressure}</strong>
+          </div>
           <div className="metric-bars">
             {pressureData.map((item) => (
               <BarMetric key={item.label} label={item.label} max={maxPressure} tone={item.tone} value={item.value} />
@@ -167,12 +195,22 @@ export function DashboardPage() {
           </div>
         </section>
 
-        <section className="panel">
+        <section className="panel chart-panel">
           <div className="section-title">
             <h3>Recent Events</h3>
             <RotateCcw size={16} />
           </div>
-          {eventData.length ? <MiniHistogram data={eventData} /> : <EmptyState title="No events yet" />}
+          {eventData.length ? (
+            <>
+              <div className="chart-summary-row">
+                <span>{events.length} latest events</span>
+                <strong>{topEvent ? topEvent.label : "No events"}</strong>
+              </div>
+              <MiniHistogram data={eventData} />
+            </>
+          ) : (
+            <EmptyState title="No events yet" />
+          )}
         </section>
       </section>
     </div>

frontend/src/pages/EventsPage.tsx

@@ -4,7 +4,6 @@ import { toast } from "sonner";
 
 import { api } from "../api";
 import { eventTitle } from "../constants";
-import { DateTime } from "../components/DateTime";
 import { EmptyState } from "../components/EmptyState";
 import type { JobEvent } from "../types";
 
@@ -15,6 +14,21 @@ function mergeEvents(current: JobEvent[], incoming: JobEvent[]) {
   return [...current, ...incoming.filter((event) => !seen.has(event.id))].sort((a, b) => b.id - a.id);
 }
 
+function eventTone(type: string) {
+  if (type.includes("fail")) return "danger";
+  if (type.includes("success")) return "success";
+  if (type.includes("retry") || type.includes("timeout")) return "warning";
+  if (type.includes("progress") || type.includes("lease")) return "info";
+  if (type.includes("claim")) return "accent";
+  return "neutral";
+}
+
+function formatLogTime(value: string) {
+  const date = new Date(value);
+  if (Number.isNaN(date.getTime())) return "--:--:--";
+  return date.toLocaleTimeString(undefined, { hour12: false });
+}
+
 export function EventsPage() {
   const [events, setEvents] = useState<JobEvent[]>([]);
   const [nextPageUrl, setNextPageUrl] = useState<string | null>(null);
@@ -22,6 +36,7 @@ export function EventsPage() {
   const [loadingMore, setLoadingMore] = useState(false);
   const [lastRefreshAt, setLastRefreshAt] = useState<string | null>(null);
   const sentinelRef = useRef<HTMLDivElement | null>(null);
+  const feedRef = useRef<HTMLDivElement | null>(null);
 
   const refreshFirstPage = useCallback(async (replace = false) => {
     if (replace) setLoading(true);
@@ -60,19 +75,12 @@ export function EventsPage() {
     }
   }, [loadingMore, nextPageUrl]);
 
-  useEffect(() => {
+  const handleFeedScroll = useCallback(() => {
-    const node = sentinelRef.current;
+    const node = feedRef.current;
-    if (!node || !nextPageUrl) return undefined;
+    if (!node || !nextPageUrl || loadingMore) return;
-
+    const distanceFromBottom = node.scrollHeight - node.scrollTop - node.clientHeight;
-    const observer = new IntersectionObserver(
+    if (distanceFromBottom <= 140) void loadMore();
-      (entries) => {
+  }, [loadMore, loadingMore, nextPageUrl]);
-        if (entries.some((entry) => entry.isIntersecting)) void loadMore();
-      },
-      { rootMargin: "280px 0px" }
-    );
-    observer.observe(node);
-    return () => observer.disconnect();
-  }, [loadMore, nextPageUrl]);
 
   const newestFirst = useMemo(() => [...events].sort((a, b) => b.id - a.id), [events]);
 
@@ -89,53 +97,43 @@ export function EventsPage() {
         </div>
       </header>
 
-      <section className="panel">
+      <section className="terminal-panel">
-        <div className="section-title">
+        <div className="terminal-header">
-          <h3>Global Event Feed</h3>
+          <div className="terminal-window-controls" aria-hidden="true">
-          <span className="muted-text">Last refresh {lastRefreshAt ? new Date(lastRefreshAt).toLocaleTimeString() : "-"}</span>
+            <i />
+            <i />
+            <i />
+          </div>
+          <code>job-events.log</code>
+          <span>refreshed {lastRefreshAt ? new Date(lastRefreshAt).toLocaleTimeString() : "-"}</span>
         </div>
-        <div className="table-wrap">
+        <div className="terminal-feed" role="log" aria-live="polite" onScroll={handleFeedScroll} ref={feedRef}>
-          <table>
+          {newestFirst.map((event) => (
-            <thead>
+            <article className={`terminal-line ${eventTone(event.type)}`} key={event.id}>
-              <tr>
+              <time className="terminal-time" dateTime={event.created_at}>
-                <th>ID</th>
+                {formatLogTime(event.created_at)}
-                <th>Event</th>
+              </time>
-                <th>Job</th>
+              <span className="terminal-prompt">$</span>
-                <th>Attempt</th>
+              <strong className="terminal-event">{eventTitle(event.type)}</strong>
-                <th>Worker</th>
+              <Link className="terminal-job" to={`/jobs/${event.job}`}>
-                <th>Created</th>
+                job:{event.job.slice(0, 8)}
-              </tr>
+              </Link>
-            </thead>
+              <span className="terminal-token">attempt:{event.attempt}</span>
-            <tbody>
+              <span className="terminal-worker">worker:{event.worker_id ?? "system"}</span>
-              {newestFirst.map((event) => (
+              {event.message && <span className="terminal-message">{event.message}</span>}
-                <tr key={event.id}>
+            </article>
-                  <td>{event.id}</td>
+          ))}
-                  <td>{eventTitle(event.type)}</td>
-                  <td>
-                    <Link className="secondary-button" to={`/jobs/${event.job}`}>
-                      {event.job.slice(0, 8)}
-                    </Link>
-                  </td>
-                  <td>{event.attempt}</td>
-                  <td>{event.worker_id ?? "-"}</td>
-                  <td>
-                    <DateTime value={event.created_at} />
-                  </td>
-                </tr>
-              ))}
-            </tbody>
-          </table>
           {loading && !newestFirst.length && <EmptyState title="Loading events" />}
           {!loading && !newestFirst.length && <EmptyState title="No events yet" />}
-        </div>
+          <div className="infinite-sentinel" ref={sentinelRef}>
-        <div className="infinite-sentinel" ref={sentinelRef}>
+            {loadingMore && <span>Loading older events...</span>}
-          {loadingMore && <span>Loading older events...</span>}
+            {!loadingMore && nextPageUrl && (
-          {!loadingMore && nextPageUrl && (
+              <button className="secondary-button" type="button" onClick={() => void loadMore()}>
-            <button className="secondary-button" type="button" onClick={() => void loadMore()}>
+                Load older events
-              Load older events
+              </button>
-            </button>
+            )}
-          )}
+            {!loadingMore && !nextPageUrl && newestFirst.length > 0 && <span>End of event history</span>}
-          {!loadingMore && !nextPageUrl && newestFirst.length > 0 && <span>End of event history</span>}
+          </div>
         </div>
       </section>
     </div>

frontend/src/pages/JobDetailPage.tsx

@@ -117,11 +117,11 @@ export function JobDetailPage() {
             {job.attempts}/{job.max_attempts}
           </strong>
         </div>
-        <div className="stat-card">
-          <span>Locked by</span>
-          <code className="code-token wrap">{job.locked_by ?? "-"}</code>
-        </div>
       </section>
+      <div className="stat-card">
+        <span>Locked by</span>
+        <code className="code-token wrap">{job.locked_by ?? "-"}</code>
+      </div>
 
       <section className="detail-grid">
         <section className="panel">

frontend/src/pages/JobsPage.tsx

@@ -1,5 +1,5 @@
-import { Eye, Plus, RotateCcw } from "lucide-react";
+import { Check, ChevronLeft, ChevronRight, Eye, Plus, RotateCcw, X } from "lucide-react";
-import { FormEvent, useCallback, useEffect, useMemo, useState } from "react";
+import { FormEvent, useCallback, useEffect, useState } from "react";
 import { Link } from "react-router-dom";
 import { toast } from "sonner";
 
@@ -21,6 +21,12 @@ const jobTypeOptions: SelectOption[] = [
   { value: "demo.flaky", label: "Flaky retry" }
 ];
 
+const pageSizeOptions: SelectOption[] = [
+  { value: "10", label: "10 / page" },
+  { value: "25", label: "25 / page" },
+  { value: "50", label: "50 / page" }
+];
+
 function demoPayload(type: string) {
   if (type === "demo.slow") return { sleep_seconds: 8 };
   if (type === "demo.timeout") return { sleep_seconds: 45 };
@@ -29,11 +35,41 @@ function demoPayload(type: string) {
   return { sleep_seconds: 1 };
 }
 
+function attemptState(job: Job, attemptNumber: number) {
+  if (attemptNumber > job.attempts) return "empty";
+  if (job.status === "succeeded") return attemptNumber === job.attempts ? "succeeded" : "failed";
+  if (job.status === "running" && attemptNumber === job.attempts) return "running";
+  return "failed";
+}
+
+function AttemptMeter({ job }: { job: Job }) {
+  return (
+    <div className="attempt-meter" aria-label={`${job.attempts} of ${job.max_attempts} attempts used`}>
+      {Array.from({ length: job.max_attempts }, (_, index) => {
+        const attemptNumber = index + 1;
+        const state = attemptState(job, attemptNumber);
+        return (
+          <span className={`attempt-square ${state}`} key={attemptNumber} title={`Attempt ${attemptNumber}: ${state}`}>
+            {state === "succeeded" && <Check size={12} strokeWidth={3} />}
+            {state === "failed" && <X size={12} strokeWidth={3} />}
+          </span>
+        );
+      })}
+      {/* <span className="attempt-count">
+        {job.attempts}/{job.max_attempts}
+      </span> */}
+    </div>
+  );
+}
+
 export function JobsPage() {
   const [jobs, setJobs] = useState<Job[]>([]);
+  const [totalJobs, setTotalJobs] = useState(0);
   const [createOpen, setCreateOpen] = useState(false);
   const [statusFilter, setStatusFilter] = useState<JobStatus | "all">("all");
   const [typeFilter, setTypeFilter] = useState("");
+  const [pageSize, setPageSize] = useState(25);
+  const [currentPage, setCurrentPage] = useState(1);
   const [jobType, setJobType] = useState("demo.success");
   const [payload, setPayload] = useState(JSON.stringify(demoPayload("demo.success"), null, 2));
   const [priority, setPriority] = useState(50);
@@ -42,8 +78,15 @@ export function JobsPage() {
   const [availableAt, setAvailableAt] = useState("");
 
   const refresh = useCallback(async () => {
-    setJobs(await api.listJobs());
+    const page = await api.listJobsPage({
-  }, []);
+      limit: pageSize,
+      offset: (currentPage - 1) * pageSize,
+      status: statusFilter === "all" ? undefined : statusFilter,
+      type: typeFilter
+    });
+    setJobs(page.results);
+    setTotalJobs(page.count);
+  }, [currentPage, pageSize, statusFilter, typeFilter]);
 
   useEffect(() => {
     void refresh().catch((caught) => toast.error(caught instanceof Error ? caught.message : String(caught)));
@@ -51,13 +94,17 @@ export function JobsPage() {
     return () => window.clearInterval(id);
   }, [refresh]);
 
-  const filteredJobs = useMemo(() => {
+  useEffect(() => {
-    return jobs.filter((job) => {
+    setCurrentPage(1);
-      if (statusFilter !== "all" && job.status !== statusFilter) return false;
+  }, [pageSize, statusFilter, typeFilter]);
-      if (typeFilter && !job.type.toLowerCase().includes(typeFilter.toLowerCase())) return false;
+
-      return true;
+  const totalPages = Math.max(1, Math.ceil(totalJobs / pageSize));
-    });
+  const firstItem = totalJobs ? (currentPage - 1) * pageSize + 1 : 0;
-  }, [jobs, statusFilter, typeFilter]);
+  const lastItem = Math.min(totalJobs, currentPage * pageSize);
+
+  useEffect(() => {
+    if (currentPage > totalPages) setCurrentPage(totalPages);
+  }, [currentPage, totalPages]);
 
   function setType(nextType: string) {
     setJobType(nextType);
@@ -156,7 +203,7 @@ export function JobsPage() {
               </tr>
             </thead>
             <tbody>
-              {filteredJobs.map((job) => (
+              {jobs.map((job) => (
                 <tr key={job.id}>
                   <td>
                     <StatusBadge status={job.status} />
@@ -166,7 +213,7 @@ export function JobsPage() {
                   </td>
                   <td>{job.priority}</td>
                   <td>
-                    {job.attempts}/{job.max_attempts}
+                    <AttemptMeter job={job} />
                   </td>
                   <td>
                     <DateTime value={job.available_at} />
@@ -181,13 +228,33 @@ export function JobsPage() {
               ))}
             </tbody>
           </table>
-          {!filteredJobs.length && <EmptyState title="No jobs match the current filter" />}
+          {!jobs.length && <EmptyState title="No jobs match the current filter" />}
+        </div>
+        <div className="pagination-bar">
+          <span>
+            Showing {firstItem}-{lastItem} of {totalJobs}
+          </span>
+          <div className="pagination-controls">
+            <SelectField value={String(pageSize)} options={pageSizeOptions} onChange={(value) => setPageSize(Number(value))} />
+            <button className="secondary-button" disabled={currentPage <= 1} type="button" onClick={() => setCurrentPage((page) => Math.max(1, page - 1))}>
+              <ChevronLeft size={16} /> Previous
+            </button>
+            <button
+              className="secondary-button"
+              disabled={currentPage >= totalPages}
+              type="button"
+              onClick={() => setCurrentPage((page) => Math.min(totalPages, page + 1))}
+            >
+              Next <ChevronRight size={16} />
+            </button>
+          </div>
         </div>
       </section>
 
       {createOpen && (
         <Modal title="Create Job" onClose={() => setCreateOpen(false)}>
           <form className="modal-form" onSubmit={createJob}>
+            <label>Quick Create</label>
             <div className="preset-grid">
               <button className="secondary-button" type="button" onClick={() => setType("demo.success")}>
                 Success
@@ -204,7 +271,7 @@ export function JobsPage() {
               <button className="secondary-button" type="button" onClick={() => setType("demo.flaky")}>
                 Flaky Retry
               </button>
-              <button className="secondary-button" type="button" onClick={() => void createBatch()}>
+              <button className="primary-button" type="button" onClick={() => void createBatch()}>
                 <RotateCcw size={16} /> 10 Mixed
               </button>
             </div>
@@ -227,9 +294,6 @@ export function JobsPage() {
               <input value={idempotencyKey} onChange={(event) => setIdempotencyKey(event.target.value)} />
             </label>
             <div className="modal-actions">
-              <button className="secondary-button" type="button" onClick={() => void createDemo(jobType, priority, maxAttempts)}>
-                Quick Create
-              </button>
               <button className="secondary-button" type="button" onClick={() => setCreateOpen(false)}>
                 Cancel
               </button>

frontend/src/styles.css

@@ -35,6 +35,9 @@
   --panel-raised: #f9fbfc;
   --background: #f4f7f9;
   --shadow: 0 18px 46px rgb(35 36 38 / 8%);
+  --terminal-scroll-thumb: #0bb3f0;
+  --terminal-scroll-thumb-hover: #f0bb0b;
+  --terminal-scroll-track: #171b1f;
   color: var(--ink);
   background: var(--background);
   font-synthesis: none;
@@ -60,6 +63,9 @@
   --panel-raised: #25282b;
   --background: #141618;
   --shadow: 0 18px 46px rgb(0 0 0 / 28%);
+  --terminal-scroll-thumb: #f0bb0b;
+  --terminal-scroll-thumb-hover: #55c8ff;
+  --terminal-scroll-track: #101316;
 }
 
 * {
@@ -175,6 +181,7 @@ label {
   grid-template-columns: 248px minmax(0, 1fr);
   grid-template-rows: 72px minmax(0, 1fr);
   min-height: 100vh;
+  transition: grid-template-columns 260ms cubic-bezier(0.22, 1, 0.36, 1);
 }
 
 .app-shell.sidebar-collapsed {
@@ -255,6 +262,10 @@ label {
   padding: 16px;
   position: sticky;
   top: 72px;
+  transition:
+    background-color 220ms ease,
+    border-color 220ms ease,
+    padding 260ms cubic-bezier(0.22, 1, 0.36, 1);
 }
 
 .sidebar-header {
@@ -268,6 +279,17 @@ label {
   text-transform: uppercase;
 }
 
+.sidebar-header span {
+  max-width: 120px;
+  opacity: 1;
+  overflow: hidden;
+  transition:
+    max-width 220ms cubic-bezier(0.22, 1, 0.36, 1),
+    opacity 160ms ease,
+    transform 220ms cubic-bezier(0.22, 1, 0.36, 1);
+  white-space: nowrap;
+}
+
 .sidebar nav {
   display: grid;
   gap: 8px;
@@ -283,10 +305,26 @@ label {
   gap: 10px;
   min-height: 42px;
   padding: 10px 12px;
+  transition:
+    background-color 180ms ease,
+    border-color 180ms ease,
+    color 180ms ease,
+    gap 240ms cubic-bezier(0.22, 1, 0.36, 1),
+    justify-content 240ms cubic-bezier(0.22, 1, 0.36, 1),
+    padding 240ms cubic-bezier(0.22, 1, 0.36, 1);
 }
 
 .nav-item span {
+  max-width: 140px;
   min-width: 0;
+  opacity: 1;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  transition:
+    max-width 220ms cubic-bezier(0.22, 1, 0.36, 1),
+    opacity 160ms ease,
+    transform 220ms cubic-bezier(0.22, 1, 0.36, 1);
+  white-space: nowrap;
 }
 
 .nav-item.active {
@@ -301,10 +339,13 @@ label {
 
 .sidebar-collapsed .sidebar-header span,
 .sidebar-collapsed .nav-item span {
-  display: none;
+  max-width: 0;
+  opacity: 0;
+  transform: translateX(-4px);
 }
 
 .sidebar-collapsed .nav-item {
+  gap: 0;
   justify-content: center;
   padding: 10px;
 }
@@ -313,6 +354,14 @@ label {
   margin: 0 auto;
 }
 
+.collapse-button {
+  transition:
+    background-color 180ms ease,
+    border-color 180ms ease,
+    margin 240ms cubic-bezier(0.22, 1, 0.36, 1),
+    transform 240ms cubic-bezier(0.22, 1, 0.36, 1);
+}
+
 .content {
   min-width: 0;
   padding: 20px;
@@ -442,6 +491,49 @@ label {
   grid-template-columns: repeat(2, minmax(0, 1fr));
 }
 
+.chart-panel {
+  overflow: hidden;
+  position: relative;
+}
+
+.chart-panel::before {
+  background: linear-gradient(90deg, var(--cyan), var(--green), var(--orange), var(--red));
+  content: "";
+  height: 3px;
+  left: 14px;
+  opacity: 0.78;
+  position: absolute;
+  right: 14px;
+  top: 0;
+}
+
+.chart-summary-row {
+  align-items: center;
+  background: var(--panel-raised);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+  display: flex;
+  gap: 12px;
+  justify-content: space-between;
+  margin-bottom: 12px;
+  min-height: 42px;
+  padding: 9px 10px;
+}
+
+.chart-summary-row span {
+  color: var(--muted);
+  font-size: 12px;
+  font-weight: 900;
+}
+
+.chart-summary-row strong {
+  font-size: 14px;
+  overflow: hidden;
+  text-align: right;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
 .detail-grid {
   display: grid;
   gap: 16px;
@@ -645,18 +737,36 @@ label {
   display: flex;
   height: 112px;
   overflow: hidden;
+  position: relative;
   width: 100%;
 }
 
+.histogram-column::before {
+  background:
+    linear-gradient(to top, transparent 24%, rgb(127 139 147 / 18%) 25%, transparent 26%),
+    linear-gradient(to top, transparent 49%, rgb(127 139 147 / 18%) 50%, transparent 51%),
+    linear-gradient(to top, transparent 74%, rgb(127 139 147 / 18%) 75%, transparent 76%);
+  content: "";
+  inset: 0;
+  pointer-events: none;
+  position: absolute;
+}
+
 .histogram-column i,
 .metric-track i {
   background: var(--accent);
   display: block;
+  transition:
+    height 520ms cubic-bezier(0.22, 1, 0.36, 1),
+    width 520ms cubic-bezier(0.22, 1, 0.36, 1),
+    background-color 180ms ease;
 }
 
 .histogram-column i {
   border-radius: 6px 6px 0 0;
+  position: relative;
   width: 100%;
+  z-index: 1;
 }
 
 .histogram-column i.queued,
@@ -703,11 +813,53 @@ label {
   margin-top: 14px;
 }
 
+.status-stack {
+  background: var(--panel-raised);
+  border: 1px solid var(--border);
+  border-radius: 999px;
+  display: flex;
+  gap: 3px;
+  height: 14px;
+  margin-bottom: 12px;
+  overflow: hidden;
+  padding: 2px;
+}
+
+.status-stack i {
+  background: var(--subtle);
+  border-radius: 999px;
+  display: block;
+  min-width: 6px;
+  transition:
+    width 520ms cubic-bezier(0.22, 1, 0.36, 1),
+    background-color 180ms ease;
+}
+
+.status-stack i.queued,
+.status-stack i.running {
+  background: var(--cyan);
+}
+
+.status-stack i.succeeded {
+  background: var(--green);
+}
+
+.status-stack i.failed {
+  background: var(--red);
+}
+
 .job-tick {
   background: var(--subtle);
   border-radius: 5px;
   display: block;
   height: 32px;
+  transition:
+    background-color 240ms ease,
+    transform 220ms ease;
+}
+
+.job-tick:hover {
+  transform: translateY(-2px);
 }
 
 .job-tick.running {
@@ -968,6 +1120,92 @@ label {
   justify-content: flex-end;
 }
 
+.pagination-bar {
+  align-items: center;
+  border-top: 1px solid var(--border);
+  color: var(--muted);
+  display: flex;
+  flex-wrap: wrap;
+  font-size: 13px;
+  font-weight: 900;
+  gap: 12px;
+  justify-content: space-between;
+  margin-top: 12px;
+  padding-top: 12px;
+}
+
+.pagination-controls {
+  align-items: center;
+  display: flex;
+  flex-wrap: wrap;
+  gap: 8px;
+  justify-content: flex-end;
+}
+
+.pagination-controls .select-field {
+  min-width: 120px;
+}
+
+.page-number-field {
+  align-items: center;
+  display: flex;
+  flex-direction: row;
+  gap: 7px;
+}
+
+.page-number-field input {
+  min-height: 38px;
+  text-align: center;
+  width: 74px;
+}
+
+.attempt-meter {
+  align-items: center;
+  display: flex;
+  flex-wrap: wrap;
+  gap: 5px;
+  min-width: 128px;
+}
+
+.attempt-square {
+  align-items: center;
+  background: var(--panel-raised);
+  border: 1px solid var(--border);
+  border-radius: 5px;
+  color: var(--muted);
+  display: inline-flex;
+  height: 22px;
+  justify-content: center;
+  width: 22px;
+}
+
+.attempt-square.succeeded {
+  background: var(--green-soft);
+  border-color: color-mix(in srgb, var(--green) 42%, var(--border));
+  color: var(--green);
+}
+
+.attempt-square.failed {
+  background: var(--red-soft);
+  border-color: color-mix(in srgb, var(--red) 42%, var(--border));
+  color: var(--red);
+}
+
+.attempt-square.running {
+  animation: attempt-running 960ms ease-in-out infinite alternate;
+  background: var(--orange-soft);
+  border-color: color-mix(in srgb, var(--orange) 42%, var(--border));
+  color: var(--orange);
+}
+
+.attempt-count {
+  color: var(--muted);
+  font-size: 12px;
+  font-weight: 900;
+  margin-left: 3px;
+  white-space: nowrap;
+}
+
 .event-feed-meta {
   align-items: center;
   display: flex;
@@ -987,6 +1225,225 @@ label {
   padding-top: 12px;
 }
 
+.terminal-panel {
+  background: #101316;
+  border: 1px solid #2d3439;
+  border-radius: 8px;
+  box-shadow: 0 22px 56px rgb(0 0 0 / 28%);
+  color: #d8e2e8;
+  overflow: hidden;
+}
+
+.terminal-header {
+  align-items: center;
+  background: #171b1f;
+  border-bottom: 1px solid #2d3439;
+  display: grid;
+  gap: 12px;
+  grid-template-columns: auto minmax(0, 1fr) auto;
+  min-height: 44px;
+  padding: 9px 12px;
+}
+
+.terminal-window-controls {
+  display: flex;
+  gap: 6px;
+}
+
+.terminal-window-controls i {
+  border-radius: 999px;
+  display: block;
+  height: 11px;
+  width: 11px;
+}
+
+.terminal-window-controls i:nth-child(1) {
+  background: #ff5f57;
+}
+
+.terminal-window-controls i:nth-child(2) {
+  background: #ffbd2e;
+}
+
+.terminal-window-controls i:nth-child(3) {
+  background: #28c840;
+}
+
+.terminal-header code {
+  background: transparent;
+  border: 0;
+  color: #d8e2e8;
+  font-size: 13px;
+  overflow: hidden;
+  padding: 0;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.terminal-header span {
+  color: #83919b;
+  font-size: 12px;
+  font-weight: 900;
+}
+
+.terminal-feed {
+  display: grid;
+  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
+  gap: 0;
+  max-height: calc(100vh - 230px);
+  min-height: 420px;
+  overflow: auto;
+  padding: 8px;
+  scrollbar-color: var(--terminal-scroll-thumb) var(--terminal-scroll-track);
+  scrollbar-width: thin;
+}
+
+.terminal-feed::-webkit-scrollbar {
+  height: 10px;
+  width: 10px;
+}
+
+.terminal-feed::-webkit-scrollbar-track {
+  background: var(--terminal-scroll-track);
+}
+
+.terminal-feed::-webkit-scrollbar-thumb {
+  background: var(--terminal-scroll-thumb);
+  border: 2px solid var(--terminal-scroll-track);
+  border-radius: 999px;
+}
+
+.terminal-feed::-webkit-scrollbar-thumb:hover {
+  background: var(--terminal-scroll-thumb-hover);
+}
+
+.terminal-feed::-webkit-scrollbar-corner {
+  background: var(--terminal-scroll-track);
+}
+
+.terminal-line {
+  align-items: baseline;
+  border-left: 3px solid transparent;
+  display: grid;
+  gap: 8px;
+  grid-template-columns: 80px 16px minmax(130px, 170px) minmax(110px, 150px) minmax(88px, 110px) minmax(150px, 220px) minmax(180px, 1fr);
+  line-height: 1.55;
+  min-width: 0;
+  padding: 7px 8px;
+}
+
+.terminal-line:nth-child(odd) {
+  background: rgb(255 255 255 / 2.5%);
+}
+
+.terminal-line:hover {
+  background: rgb(255 255 255 / 6%);
+}
+
+.terminal-line.success {
+  border-left-color: #42d392;
+}
+
+.terminal-line.danger {
+  border-left-color: #ff6b6b;
+}
+
+.terminal-line.warning {
+  border-left-color: #f5b84b;
+}
+
+.terminal-line.info {
+  border-left-color: #55c8ff;
+}
+
+.terminal-line.accent {
+  border-left-color: #b388ff;
+}
+
+.terminal-time,
+.terminal-token,
+.terminal-worker,
+.terminal-message {
+  color: #8d9aa5;
+  font-size: 12px;
+  min-width: 0;
+  overflow-wrap: anywhere;
+}
+
+.terminal-prompt {
+  color: #63717b;
+}
+
+.terminal-event {
+  color: #d8e2e8;
+  font-size: 12px;
+  min-width: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  text-transform: uppercase;
+  white-space: nowrap;
+}
+
+.terminal-line.success .terminal-event,
+.terminal-line.success .terminal-prompt {
+  color: #42d392;
+}
+
+.terminal-line.danger .terminal-event,
+.terminal-line.danger .terminal-prompt {
+  color: #ff6b6b;
+}
+
+.terminal-line.warning .terminal-event,
+.terminal-line.warning .terminal-prompt {
+  color: #f5b84b;
+}
+
+.terminal-line.info .terminal-event,
+.terminal-line.info .terminal-prompt {
+  color: #55c8ff;
+}
+
+.terminal-line.accent .terminal-event,
+.terminal-line.accent .terminal-prompt {
+  color: #b388ff;
+}
+
+.terminal-job {
+  color: #9ae6ff;
+  font-size: 12px;
+  font-weight: 900;
+  min-width: 0;
+  overflow-wrap: anywhere;
+  text-decoration: none;
+}
+
+.terminal-job:hover {
+  color: #ffffff;
+}
+
+.terminal-message {
+  color: #c0ccd4;
+}
+
+.terminal-feed .empty-state {
+  background: rgb(255 255 255 / 4%);
+  border-color: #2d3439;
+  color: #8d9aa5;
+}
+
+.terminal-panel .infinite-sentinel {
+  border-top: 1px solid #2d3439;
+  color: #8d9aa5;
+  padding: 12px;
+}
+
+.terminal-panel .secondary-button {
+  background: #171b1f;
+  border-color: #2d3439;
+  color: #d8e2e8;
+}
+
 .filter-grid {
   grid-template-columns: repeat(4, minmax(0, 1fr));
 }
@@ -1327,6 +1784,16 @@ code {
   }
 }
 
+@keyframes attempt-running {
+  from {
+    box-shadow: 0 0 0 0 color-mix(in srgb, var(--orange) 18%, transparent);
+  }
+
+  to {
+    box-shadow: 0 0 0 4px color-mix(in srgb, var(--orange) 4%, transparent);
+  }
+}
+
 @media (prefers-reduced-motion: reduce) {
   *,
   *::before,
@@ -1399,6 +1866,10 @@ code {
   .filter-grid {
     grid-template-columns: 1fr 1fr;
   }
+
+  .terminal-line {
+    grid-template-columns: 80px 16px minmax(120px, 1fr) minmax(100px, 1fr);
+  }
 }
 
 @media (max-width: 720px) {
@@ -1496,4 +1967,28 @@ code {
   .dot-chart-row {
     grid-template-columns: 1fr;
   }
+
+  .terminal-header {
+    grid-template-columns: auto minmax(0, 1fr);
+  }
+
+  .terminal-header span {
+    grid-column: 2;
+  }
+
+  .terminal-feed {
+    max-height: none;
+    min-height: 360px;
+  }
+
+  .terminal-line {
+    grid-template-columns: 64px 14px minmax(0, 1fr);
+  }
+
+  .terminal-job,
+  .terminal-token,
+  .terminal-worker,
+  .terminal-message {
+    grid-column: 3;
+  }
 }

frontend/src/types.ts

@@ -36,6 +36,13 @@ export type CursorPage<T> = {
   results: T[];
 };
 
+export type LimitOffsetPage<T> = {
+  count: number;
+  next: string | null;
+  previous: string | null;
+  results: T[];
+};
+
 export type JobStats = {
   total: number;
   by_status: Record<JobStatus, number>;

slides/index.html

@@ -0,0 +1,19 @@
+<!doctype html>
+<html lang="en">
+<head>
+  <meta charset="utf-8" />
+  <meta name="viewport" content="width=device-width, initial-scale=1" />
+  <title>Minimal PostgreSQL Job Queue - Interview Presentation</title>
+  <link rel="stylesheet" href="styles.css" />
+</head>
+<body>
+  <div class="top-progress" aria-hidden="true">
+    <span id="progressFill"></span>
+  </div>
+
+  <main class="deck" aria-live="polite"></main>
+  <aside class="notes" id="notes" aria-label="speaker notes"></aside>
+
+  <script src="slides.js"></script>
+</body>
+</html>

slides/slides.js

@@ -0,0 +1,259 @@
+const slides = [
+  {
+    eyebrow: '01 / Opening',
+    title: 'Minimal PostgreSQL Job Queue',
+    subtitle: 'A small queue that proves safe claim, deterministic state, and visible execution.',
+    image: 'images/01-cover.png',
+    notes: [
+      'Open by framing the assignment: build an internal job queue, not a full queue product.',
+      'The main promise is correctness: multiple workers can run, but a single job receives a single execution owner.',
+      'The implementation is intentionally small so every important behavior is explainable during the interview.'
+    ]
+  },
+  {
+    eyebrow: '02 / Problem',
+    title: 'What the Assignment Really Tests',
+    subtitle: 'Create jobs, claim them safely, manage states, and trace what happened.',
+    image: 'images/02-contract.png',
+    notes: [
+      'The assignment asks for job creation, worker claim, job status management, and execution tracking.',
+      'The central invariant is: one job must not be claimed and executed by two workers at the same time.',
+      'It also asks that worker failure behavior and the main status transitions are clear and testable.'
+    ]
+  },
+  {
+    eyebrow: '03 / Scope',
+    title: 'Small Queue, Not a Queue Platform',
+    subtitle: 'The design keeps the model minimal and moves complexity into deterministic rules.',
+    image: 'images/03-scope.png',
+    notes: [
+      'There is one internal priority queue, not user-defined queues.',
+      'There is no queue table and no worker table. Workers are ephemeral process threads configured through settings and environment variables.',
+      'Authentication and advanced operator permissions are deliberately omitted for interview simplicity, but documented as production follow-ups.'
+    ]
+  },
+  {
+    eyebrow: '04 / Architecture',
+    title: '1 Database, 2 Django Roles, 1 UI',
+    subtitle: 'The API exposes queue operations; the worker process claims jobs from PostgreSQL.',
+    image: 'images/04-architecture.png',
+    notes: [
+      'React is only the demo and observability surface. It does not own queue state.',
+      'Django API creates jobs, lists jobs and events, exposes stats, and supports manual retry of failed jobs.',
+      'The worker is a separate Django process with N configured threads; each thread claims work from PostgreSQL.'
+    ]
+  },
+  {
+    eyebrow: '05 / Model',
+    title: 'Two Tables Are Enough',
+    subtitle: 'The job row carries state; the event row explains the history.',
+    image: 'images/05-model.png',
+    notes: [
+      '<code>jobs</code> stores type, payload, status, priority, available time, attempts, max attempts, lock owner, lock deadline, result, and timestamps.',
+      '<code>job_events</code> is append-only observability: created, claimed, progress, lease renewed, retry scheduled, timeout requeued, succeeded, failed, and manual retry.',
+      'Database constraints validate row shape: queued jobs have no lock, running jobs must have a lock, and terminal jobs must have a finish timestamp.'
+    ]
+  },
+  {
+    eyebrow: '06 / State',
+    title: 'Status Transitions Are Explicit',
+    subtitle: 'The queue allows only meaningful movement between queued, running, succeeded, and failed.',
+    image: 'images/07-state.png',
+    notes: [
+      'The normal path is queued -> running -> succeeded.',
+      'Failure or timeout can move running back to queued when attempts remain.',
+      'When attempts are exhausted, the job becomes failed. Manual retry can move failed back to queued and resets the attempt count.'
+    ]
+  },
+  {
+    eyebrow: '07 / Safe Claim',
+    title: 'PostgreSQL Chooses the Winner',
+    subtitle: 'Atomic claim uses row locks and SKIP LOCKED to avoid double execution.',
+    image: 'images/06-claim.png',
+    notes: [
+      'The worker selects the next eligible queued job ordered by priority, available_at, created_at, and id.',
+      'Inside one transaction, it uses <code>SELECT ... FOR UPDATE SKIP LOCKED</code>, then marks the row running, increments attempts, and sets the lease.',
+      'When many threads race, one locks the row; the others skip it instead of waiting and accidentally claiming the same job.'
+    ]
+  },
+  {
+    eyebrow: '08 / Ownership',
+    title: 'Current Owner + Attempt Is the Write Token',
+    subtitle: 'A stale worker cannot complete or fail a job after ownership changes.',
+    image: 'images/08-ownership.png',
+    notes: [
+      'Completion, failure, progress, and lease renewal all filter by job id, running status, locked_by, and attempt.',
+      'That means a worker that crashed and later wakes up cannot complete attempt 1 after the job was requeued and claimed as attempt 2.',
+      'This is the practical guardrail that makes lease recovery safe.'
+    ]
+  },
+  {
+    eyebrow: '09 / Recovery',
+    title: 'Worker Failure Is a Timeout, Not a Mystery',
+    subtitle: 'Expired leases are cleaned up deterministically.',
+    image: 'images/09-recovery.png',
+    notes: [
+      'Workers periodically run cleanup for running jobs whose locked_until is in the past.',
+      'If attempts remain, the job is requeued and a timeout event is recorded. If attempts are exhausted, it becomes failed.',
+      'This queue provides at-least-once execution, not exactly-once execution. External side-effect handlers should be idempotent.'
+    ]
+  },
+  {
+    eyebrow: '10 / Retry',
+    title: 'Retries Are Bounded and Scheduled',
+    subtitle: 'Failures return to the queue with deterministic exponential backoff.',
+    image: 'images/10-retries.png',
+    notes: [
+      '<code>fail_job</code> either schedules the next attempt or marks the job failed when max_attempts is reached.',
+      'Backoff is deterministic and stored through available_at, so workers do not need hidden memory.',
+      'Idempotency keys prevent duplicate producer submissions for the same logical job.'
+    ]
+  },
+  {
+    eyebrow: '11 / UI',
+    title: 'Demo-Friendly Observability',
+    subtitle: 'The UI shows state, pressure, attempts, leases, and event history while workers run.',
+    image: 'images/11-ui.png',
+    notes: [
+      'Dashboard polls jobs, stats, events, and health every 2 seconds.',
+      'Jobs page uses limit-offset pagination, status/type filters, and refreshes every 2 seconds.',
+      'Job detail polls the job and its timeline every 1 second; global events use cursor pagination and fetch older pages as the terminal log scrolls.'
+    ]
+  },
+  {
+    eyebrow: '12 / Tests',
+    title: 'Tests Target the Risky Parts',
+    subtitle: 'The most important tests are around ownership, concurrency, and recovery.',
+    image: 'images/12-tests.png',
+    notes: [
+      'There are service-level tests for successful claim, deterministic ordering, idempotent creation, retry scheduling, exhausted failure, timeout cleanup, stale worker rejection, and lease renewal ownership.',
+      'The PostgreSQL concurrency test runs multiple claimers and asserts only one claimed event exists.',
+      'API tests cover job pagination, filters, cursor-based global events, and older-page loading.'
+    ]
+  },
+  {
+    eyebrow: '13 / Trade-off',
+    title: 'PostgreSQL Now, Broker Later',
+    subtitle: 'PostgreSQL is ideal for this interview; Redis or a broker is the scale path.',
+    image: 'images/13-tradeoff.png',
+    notes: [
+      'The assignment requires PostgreSQL, and PostgreSQL makes the correctness story compact and inspectable.',
+      'For very high throughput, cross-service distribution, or advanced queue features, I would move to a Redis-backed or dedicated broker design.',
+      'The important point is that I did not hide over-engineering in the interview implementation; I documented it as a next architecture.'
+    ]
+  },
+  {
+    eyebrow: '14 / Close',
+    title: 'What This Proves',
+    subtitle: 'Minimal implementation with production-aware guarantees.',
+    image: 'images/14-takeaway.png',
+    notes: [
+      'The system is safe because PostgreSQL owns the claim decision.',
+      'It is deterministic because state transitions and row shapes are explicit and validated.',
+      'It is demoable because the UI and events make execution visible without adding unnecessary queue models.'
+    ]
+  }
+];
+
+const deck = document.querySelector('.deck');
+const notes = document.getElementById('notes');
+const progressFill = document.getElementById('progressFill');
+
+let current = Math.max(0, Math.min(slides.length - 1, Number(location.hash.replace('#', '')) - 1 || 0));
+let notesOpen = false;
+
+function renderDeck() {
+  deck.innerHTML = slides.map((slide, index) => `
+    <section class="slide" data-index="${index}" aria-hidden="${index === current ? 'false' : 'true'}">
+      <header class="slide-header">
+        <span class="eyebrow">${slide.eyebrow}</span>
+        <h1>${slide.title}</h1>
+        <p class="subtitle">${slide.subtitle}</p>
+      </header>
+      <div class="visual"><img src="${slide.image}" alt="${slide.title} visual" /></div>
+    </section>
+  `).join('');
+  update(false);
+}
+
+function update(shouldUpdateHash = true) {
+  deck.querySelectorAll('.slide').forEach((slide, index) => {
+    slide.classList.toggle('active', index === current);
+    slide.setAttribute('aria-hidden', index === current ? 'false' : 'true');
+  });
+
+  progressFill.style.transform = `scaleX(${(current + 1) / slides.length})`;
+
+  if (shouldUpdateHash) {
+    location.hash = String(current + 1);
+  }
+
+  renderNotes();
+}
+
+function renderNotes() {
+  const slide = slides[current];
+  notes.innerHTML = `<h2>Speaker notes - ${String(current + 1).padStart(2, '0')}. ${slide.title}</h2><ul>${slide.notes.map((note) => `<li>${note}</li>`).join('')}</ul>`;
+  notes.classList.toggle('open', notesOpen);
+}
+
+function next() {
+  if (current < slides.length - 1) {
+    current += 1;
+    update();
+  }
+}
+
+function prev() {
+  if (current > 0) {
+    current -= 1;
+    update();
+  }
+}
+
+function toggleNotes() {
+  notesOpen = !notesOpen;
+  renderNotes();
+}
+
+document.addEventListener('keydown', (event) => {
+  if (['ArrowRight', 'PageDown', ' '].includes(event.key)) {
+    event.preventDefault();
+    next();
+  }
+
+  if (['ArrowLeft', 'PageUp'].includes(event.key)) {
+    event.preventDefault();
+    prev();
+  }
+
+  if (event.key === 'Home') {
+    current = 0;
+    update();
+  }
+
+  if (event.key === 'End') {
+    current = slides.length - 1;
+    update();
+  }
+
+  if (event.key.toLowerCase() === 'n') {
+    toggleNotes();
+  }
+
+  if (event.key === 'Escape' && notesOpen) {
+    notesOpen = false;
+    renderNotes();
+  }
+});
+
+window.addEventListener('hashchange', () => {
+  const nextIndex = Number(location.hash.replace('#', '')) - 1;
+
+  if (Number.isFinite(nextIndex) && nextIndex >= 0 && nextIndex < slides.length && nextIndex !== current) {
+    current = nextIndex;
+    update(false);
+  }
+});
+
+renderDeck();

slides/styles.css

@@ -0,0 +1,290 @@
+:root {
+  --bg: #f8fbff;
+  --ink: #0f172a;
+  --muted: #64748b;
+  --accent: #2563eb;
+  --accent-strong: #7c3aed;
+  --line: #e2e8f0;
+}
+
+* {
+  box-sizing: border-box;
+}
+
+html,
+body {
+  height: 100%;
+  margin: 0;
+}
+
+body {
+  overflow: hidden;
+  background:
+    linear-gradient(180deg, #ffffff 0%, var(--bg) 42%, #eef6ff 100%);
+  color: var(--ink);
+  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
+}
+
+.top-progress {
+  position: fixed;
+  top: 0;
+  left: 0;
+  z-index: 30;
+  width: 100vw;
+  height: 5px;
+  overflow: hidden;
+  background: rgba(226, 232, 240, .82);
+}
+
+.top-progress span {
+  display: block;
+  width: 100%;
+  height: 100%;
+  background: linear-gradient(90deg, var(--accent), var(--accent-strong));
+  transform: scaleX(0);
+  transform-origin: left center;
+  transition: transform 420ms cubic-bezier(.22, 1, .36, 1);
+}
+
+.deck {
+  position: relative;
+  width: 100vw;
+  height: 100dvh;
+}
+
+.slide {
+  position: absolute;
+  inset: 0;
+  display: grid;
+  grid-template-rows: max-content minmax(0, 1fr);
+  gap: clamp(14px, 2vh, 24px);
+  height: 100dvh;
+  padding: clamp(34px, 5vh, 58px) clamp(20px, 4.8vw, 74px) clamp(20px, 4vh, 42px);
+  opacity: 0;
+  pointer-events: none;
+  transform: translateY(10px);
+  transition:
+    opacity 180ms ease,
+    transform 220ms ease;
+}
+
+.slide.active {
+  z-index: 2;
+  opacity: 1;
+  pointer-events: auto;
+  transform: translateY(0);
+}
+
+.slide-header {
+  width: 100%;
+  margin: 0;
+  text-align: center;
+}
+
+.eyebrow {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  height: 30px;
+  margin-bottom: 16px;
+  padding: 0 14px;
+  border: 1px solid var(--line);
+  border-radius: 999px;
+  background: rgba(255, 255, 255, .86);
+  color: var(--accent);
+  font-size: 13px;
+  font-weight: 800;
+  letter-spacing: .12em;
+  text-transform: uppercase;
+  box-shadow: 0 10px 26px rgba(15, 23, 42, .05);
+}
+
+h1 {
+  margin: 0;
+  font-size: clamp(42px, 5vw, 72px);
+  font-weight: 900;
+  letter-spacing: -0.055em;
+  line-height: .96;
+}
+
+.subtitle {
+  margin: 18px auto 0;
+  color: var(--muted);
+  font-size: clamp(18px, 2vw, 25px);
+  font-weight: 650;
+  line-height: 1.35;
+}
+
+.visual {
+  display: flex;
+  justify-content: center;
+  width: 100%;
+  height: 100%;
+  min-height: 0;
+}
+
+.visual img {
+  display: block;
+  width: auto;
+  height: 100%;
+  max-width: 100%;
+  max-height: 100%;
+  object-fit: contain;
+}
+
+.notes {
+  position: fixed;
+  left: 50%;
+  bottom: 34px;
+  z-index: 20;
+  width: min(1060px, calc(100vw - 60px));
+  max-height: 38vh;
+  overflow: auto;
+  padding: 22px 26px;
+  border: 1px solid rgba(255, 255, 255, .13);
+  border-radius: 24px;
+  background: rgba(15, 23, 42, .94);
+  box-shadow: 0 24px 60px rgba(2, 6, 23, .35);
+  color: #e2e8f0;
+  opacity: 0;
+  pointer-events: none;
+  transform: translateX(-50%) translateY(24px);
+  transition: opacity 180ms ease, transform 180ms ease;
+}
+
+.notes.open {
+  opacity: 1;
+  pointer-events: auto;
+  transform: translateX(-50%) translateY(0);
+}
+
+.notes h2 {
+  margin: 0 0 10px;
+  color: #fff;
+  font-size: 18px;
+  letter-spacing: .01em;
+}
+
+.notes ul {
+  display: grid;
+  gap: 7px;
+  margin: 0;
+  padding-left: 22px;
+}
+
+.notes li {
+  color: #cbd5e1;
+  font-size: 15px;
+  line-height: 1.5;
+}
+
+.notes code {
+  padding: 1px 5px;
+  border: 1px solid rgba(147, 197, 253, .15);
+  border-radius: 6px;
+  background: rgba(37, 99, 235, .16);
+  color: #bfdbfe;
+}
+
+@media (max-width: 800px) {
+  .slide {
+    padding: 34px 24px 24px;
+  }
+
+  .visual img {
+    height: 100%;
+    max-width: 100%;
+  }
+}
+
+@media (max-width: 1536px), (max-height: 850px) {
+  .eyebrow {
+    height: 28px;
+    margin-bottom: 12px;
+    font-size: 11px;
+  }
+
+  h1 {
+    font-size: clamp(32px, 4.1vw, 56px);
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+
+  .subtitle {
+    margin-top: 12px;
+    font-size: clamp(15px, 1.55vw, 20px);
+  }
+}
+
+@media (max-height: 720px) {
+  .slide {
+    gap: 12px;
+    padding-top: 28px;
+    padding-bottom: 18px;
+  }
+
+  .eyebrow {
+    height: 26px;
+    margin-bottom: 10px;
+    font-size: 11px;
+  }
+
+  h1 {
+    font-size: clamp(30px, 6vh, 48px);
+  }
+
+  .subtitle {
+    margin-top: 10px;
+    font-size: clamp(14px, 2.4vh, 18px);
+  }
+}
+
+@media (max-height: 560px) {
+  .slide {
+    padding-top: 18px;
+    padding-bottom: 14px;
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+  .eyebrow {
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+  h1 {
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+
+  .subtitle {
+    font-size: clamp(14px, 3vh, 17px);
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+}
+
+@media (prefers-reduced-motion: reduce) {
+  .top-progress span,
+  .slide,
+  .notes {
+    transition: none;
+  }
+}
+
+@media print {
+  body {
+    overflow: visible;
+    background: #fff;
+  }
+
+  .top-progress,
+  .notes {
+    display: none;
+  }
+
+  .deck {
+    height: auto;
+  }
+
+  .slide {
+    position: relative;
+    min-height: 100vh;
+    page-break-after: always;
+    opacity: 1;
+    pointer-events: auto;
+    transform: none;
+  }
+}