Open to everyone · Free to start
Don't just deploy. Watch it scale.
System design you can click through, in production. Set up a real app, send users at it, and see what happens: copies, load balancing and failures, live.
Free: 2 apps and 5 static websites, no card. Colleges get cohort plans with live teaching.
How it works
From a click to a system you can stress-test
Most tools stop at “it's deployed”. This is where it gets interesting.
- 1
Click through the setup
Pick a sample app or connect GitHub. No Dockerfile and no servers to configure: it builds and goes live at its own HTTPS address.
- 2
Send users at it
Press the load-test button to send real traffic at your own app, and see how it holds up as the numbers climb.
- 3
Watch it respond
Live CPU, memory and request charts as copies are added and removed, with zero-downtime rollouts and one-click rollbacks.
The free plan includes a small taste: up to 2 copies of an app and the load-test button. Standard, Pro and cohort plans open the full playground, with more copies and autoscaling.
The playground
Learn system design by running it
Real containers, real traffic, real consequences. Pick a topic, change something, and see what happens.
- In the free plan
Scaling and replicas
Run several copies of your app and see CPU and memory for each, live. Add and remove copies yourself.
- In the free plan
Load balancing and failover
Traffic is shared across your copies. Stop one and watch the others carry on.
- Standard, Pro, cohorts
Autoscaling
Set a CPU target and let the platform add and remove copies as traffic moves.
- In the free plan
A load-test button
Send steady traffic at your own app for a short time and see what came back and what the copies did.
- In the free plan
Zero-downtime rollouts and rollbacks
Every deploy is a release. Roll out with no gap, and go back to an earlier one in a click.
- Standard, Pro, cohorts
Managed PostgreSQL
A private database you link to your app in one click, backed up every night.
Coming next
- Coming soon
Debug lab
A terminal inside your running app, live logs, restart and stop from the console.
- Coming soon
Caching with Redis
A managed cache you link to your app, to see how it takes load off the database.
- Coming soon
Data lab
Read replicas, one-click restore and recovery to an exact moment in time.
- Coming soon
Guided lessons and an assistant
Courses with an app to deploy, then break and fix, and an assistant that knows your own apps.
Plans
Free to start. Room to grow.
Anyone can sign up. Standard and Pro are on their way, and colleges can take a cohort plan.
Free
Live nowEverything to deploy your first projects.
- 2 apps
- 5 static websites
- A secure HTTPS address for each
- Auto-deploy from GitHub on every push
- Sample apps and a guided start
- 120 build minutes a month
- Up to 2 copies of an app, with load balancing and a load-test button
Standard
Coming soonMore room to build.
- Higher limits on apps and websites
- Your own domain with HTTPS
- The scaling playground and load tests
- Details and prices to be announced
Pro
Coming soonThe full systems playground.
- Everything in Standard
- Managed databases
- More copies, autoscaling and bigger apps
- Details and prices to be announced
Be first to know when Standard and Pro open
No prices yet. People on this list hear first, and nothing else is sent.
For colleges
Cohort plans
Higher limits, the labs for less, and live teaching for your whole batch, with your placement cell in charge.
For colleges and universities
Give your whole batch the playground, with a teacher
Anyone can sign up alone. A cohort plan gives a college more: higher limits, the labs for less, and live teaching.
Higher limits
More apps, websites, CPU and build minutes for every student than a free account.
The labs for less
The full systems playground at a lower cost per student than an individual plan.
Live teaching
Learn from instructors, live. Sessions teach the why behind each lab, so students understand the system, not just the clicks.
Progress your placement cell can see
Who joined, who shipped, who deploys on every push, and an audit log of what changed.
Hiring opportunitiesComing soon
A way for your strongest builders to get in front of hiring partners.
Already using ZeroTo? Share your invite link from your dashboard.
Built for the real thing
Production rigor, with the guard-rails built in
Isolated by default
Everyone gets their own namespace and a locked-down container, behind a firewall that keeps user code away from the platform’s own network.
Secrets that stay secret
API keys and passwords are encrypted, hidden once saved, and kept out of build logs. Build-only secrets never reach the running app.
Fair resource limits
CPU, memory and build minutes are capped per plan — per app and in total — so one runaway project never slows anyone else down.
A clear audit trail
Colleges’ admins see who did what: sign-ins, deploys, variable changes, rollbacks, invites. Secret values are never recorded.
Resilient by design
Crashed apps restart, work on a failed server is rescheduled, interrupted builds start again, and every database, the platform’s and yours, is backed up every night.
Sleeps when idle, wakes itself
Idle apps stop to free the machine and start again the moment someone visits. Unused databases pause, and keep every row, until a student starts them.
FAQ
Questions people ask us
Is it really free?
Yes. The free plan gives you 2 apps and 5 static websites, with no card needed. Free seats are limited at first: if they are full when you sign up, you will see that straight away. Standard and Pro are coming soon; leave your email under Plans and we will tell you the day they open.
What is the system design playground?
A place to run a real app and see what happens as traffic grows: add copies of it, watch traffic being shared between them, press the load-test button, follow CPU and requests live, and roll out and back with no downtime. More labs are on the way, such as a terminal and live logs, caching, and a data lab. The free plan includes a small taste: up to 2 copies of an app and the load-test button. Standard, Pro and cohort plans open the full playground, with more copies and autoscaling.
Do I need to know Docker already?
No. A Dockerfile is optional: without one we detect the language (Node, Python, Go, static sites and more) and build it, and with one we use it. The new-deployment screen shows a working example, and build logs make it obvious what went wrong when something does.
Can I host a website, not just a server app?
Yes. A front end that builds into plain files, such as HTML, React or Vite, is detected automatically and published as a static site. It needs no server to size, keeps every version so a rollback takes seconds, and can call your own app and database.
What happens to an app nobody is using?
It goes to sleep to free capacity and wakes by itself on the next visit; the first request after a long idle takes a few seconds longer. Static sites never sleep. Databases that are unused for a while are paused, never deleted.
Is this a simulator?
No. Every deployment is a real image built from your repository, running as a real container, reachable over a real domain with a real TLS certificate. The traffic in a load test is real too.
I'm at a college. Do I need an invite?
No. You can sign up on your own any time. If your college sets up a cohort, you will get an invite to join it, with higher limits and live teaching.
How do cohort plans work for colleges?
Your college gets its own organization on a plan sized to the batch: higher limits, the labs for less than individual plans, and live teaching. Your admins invite students individually or from a CSV and see who is shipping. Ask for a cohort on the college page and we will set it up. Hiring opportunities for strong builders are coming soon.
Is our data backed up?
The platform's database and every managed database are backed up every night to cloud storage (and a database is backed up again before it is paused or deleted); restores are tested rather than assumed. Every version of a static site is kept there too, and container images live alongside. Your source code stays in your own GitHub repositories.
Ship it. Then stress-test it.
Sign up free and have your first app live in minutes. Bringing a whole batch? Ask for a cohort.