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Design a Reactive Database (Live Queries)/Playground

Live queries: screens that update in real time

Click a part to change it, put something in front of it, or kill it. Turn the traffic up. Every number moves as you go; nothing is graded. About 40,000 people online at peak with five live queries each, and 2,000 mutations a second.

Running
Traffic
CLIENTWeb andmobile appsSERVICESync serversSERVICEFunction runnersDATABASEVersioned storeSERVICECommitterSERVICESubscriptiontrackerCACHEResult cache
Requests failing
0%
Backlog growing
none
Instances running
45

What goes through it

OperationOfferedOutcomeWaitUp
Mutations2,000/sAll served115 ms99.9%
Query re-runs10k/sAll served58 ms99.95%
Cached results30k/sAll served51 ms99.999%
Invalidationsbackground2,000/sKeeping up––

Wait is the expected time a caller waits; Up is the share of time every part it waits on is running.

What your changes did

Nothing yet. This is the reference design: change something to see what it buys and costs.

At this traffic

Ask AI what your design does

AI

The numbers above come from a simple model. The AI reads your design, what you changed and these numbers, and explains where it holds and where it fails, citing how the engineers who built it did it. It can be wrong.