Uptime: A Cloud Provider Sim

You don't manage a datacenter from a spreadsheet. You walk it.

Uptime puts you on the floor of your own cloud provider, first person, hands on the hardware. You buy the servers and carry them to the rack. You seat them with a click. You run the cable off the spool yourself, find the port, watch it lay across the floor, and power the thing on. Then you sign your first customer and find out whether any of it holds.

Underneath the floor is a real simulation. Every server, switch, cable and port is a live entity in a deterministic engine, and the network switches and routes real traffic across it. Power and cooling are budgets you can blow. Capacity is hardware that fills up. When something breaks, it breaks because the model says it should, and the fix is usually the one a real engineer would reach for. That was the whole goal: a build-it-with-your-hands tycoon sim that still holds up if you do this for a living.

Get it running, then keep it running. The moment traffic arrives, the simulation starts pushing back.

You're running the cloud, not a server room.

You own the full stack. The metal, the network, the services you sell, and the customers whose product lives on your kit. You're the thing they build on, so everything running on you is yours to keep alive, from the single box in the garage to a floor other companies depend on.

Your customers bet their business on you.

The tenants have names, and they hand you their product expecting it to stay up. Reputation is the currency underneath all of it. You earn it slowly and you can lose it in one bad night, and the bigger the customer, the harder that fall lands. Sign a deal you can't carry, pack one host too tight, sleep through an SLA breach at 2am, and the money is the cheap part. You lose the trust that was about to send you the next customer.

So every yes is a wager on whether you can carry the new weight without dropping what you already hold. Turning business away is sometimes the correct call. The tenants you keep won't sit quietly either. They surge, they haggle, and they come back asking for more capacity, expecting a yes. The yes costs iron. One eats bandwidth. The next wants far more memory than its size suggests, and the one after that wants CPU nobody else is allowed to touch. Keep them happy and they say so out loud, and they bring friends.

What you sell is infrastructure you actually run.

Customers don't rent "a server." They spin up the things a real cloud sells: virtual machines, object storage, managed databases, Kubernetes, load balancers, serverless functions. Each one is a service you operate. Behind every service is a control plane you have to keep alive and an agent on each host that does the work, and all of it competes for the same compute your customers are paying for.

That's where the network grows teeth. Cut a service off from its control plane and it starts to fail. Lean on one too hard and it buckles. Capacity runs out, the network can partition the very services you're selling, and the way you lay it all out is what separates a provider that holds from one that tips over.

The simulation is the game.

This is where the word "simulation" gets earned. Every device on your floor is a real entity in a deterministic engine, and every LED you see is reading its live state. A link saturates because the math saturated it. A rack goes dark because a fault domain you never thought about turned out to be a single point of failure.

Ports, cables, power draw, fault domains, oversubscription, link aggregation, spanning tree, BGP, mean-time-between-failures. These are the model, not labels stuck on a progress bar. Cable a redundant link the wrong way and spanning tree either saves you or, if you got it backwards, the whole floor drowns in a broadcast storm. You can ignore the depth and still win. You can also lean all the way into it.

Then the internet notices you.

Floods arrive, and they arrive more often the bigger you get. Attack volume scales with how many tenants you host, how well known you are and how much line there is to fill. The garage is where you meet the mechanic. On a colo floor it starts to hurt. An attack can't come down the wire faster than the wire allows, so a consumer fibre and a carrier circuit get attacked in completely different shapes.

Your gateway and its add-ons scrub what they can absorb, and the traffic you absorbed still filled your pipe on the way in. Your servers are protected. Your line is not. At most four fifths of a circuit can be taken, so a flood squeezes you for a while instead of switching you off. Buy more inspection capacity, or buy more line. There's an intrusion feed to read while it happens, and a bill afterwards, because security hardware carries monthly fees and licences that show up in your burn rate.

Yes, it has a /metrics endpoint.

Every running game serves a read-only HTTP API on localhost, and the ops console tells you the port. Curl it. Scrape it. Hosts, racks, cables, switche…