Live Kubernetes workspaces

Learn system design by actually building it

Everyone else stops at the whiteboard. Here the diagram is a running Kubernetes namespace — edit the code in your browser, redeploy, and watch the traffic move.

Start free with Google Browse challenges

Free · No credit card · Nothing to install

Nginx Load Balancer

60 min

1 of 2 backends serving

How it works

Step 1

Start a workspace

Pick a published challenge and spin up an isolated namespace in seconds.

Step 2

Edit & redeploy

Change editable workloads in the in-browser editor, rebuild, and roll out.

Step 3

Watch it live

Stream metrics, logs, and API stats while controlled traffic hits your system.

Step 4

Submit & score

Automated judging grades each workload and ranks you on the leaderboard.

One screen, the whole loop

Every challenge opens a private Kubernetes namespace with the problem, an editor, and live telemetry from your own running system — side by side. Click through to see it.

Nginx Load Balancer

58m 12sSubmit

Nginx Load Balancer

Traffic is served by two identical backends — but nginx sends everything to the first one. Under steady load it saturates: requests queue, latency climbs, and the second backend sits idle.

Success criteria

· No failed requests
· Both backends verifiably serving

Dev VM — nginx.conf

1upstream flask_backend {
2    server flask-app-1:80;
3
4    # Uncomment to balance:
5    # server flask-app-2:80;
6}
7
8server {
9    location / {
10        proxy_pass http://flask_backend;
11    }
12}

Start free. Upgrade when you outgrow it.

Real clusters cost real money to run, so time on one is what you pay for — not seats, not features you will never touch.

Free

Every challenge, a couple of hours a day.

Free forever. No card.

Start free

Every challenge, every track
2 challenge-hours a day
1 workspace at a time
Streaks, badges and the leaderboard

Pro

Enough hours that you stop counting them.

$15/ month

Billed monthly. Cancel any time.

Every challenge, every track
12 challenge-hours a day
1 workspace at a time
Streaks, badges and the leaderboard

Full comparison and FAQ

Ready to build something live?

Browse the catalog and start your first challenge — no setup, no local cluster, just a workspace in your browser.

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