Observed arrival · 2026-11-11
ScaleMySytem’s system-design failure simulator
A browser-based simulator for learning system design by testing architectures against traffic, failures, and cost trade-offs.
○Open
⊠Login
$Paid
†Ads
✦Pretty
●Pro
◎Niche
◉Human
⚑Risk
ƒJS
- For
- Engineers preparing for system-design interviews
- Worth noticing
- The example adds a read replica for $447 more per month, then compares success, p99 latency, and monthly cloud cost.
Field notes
The featured exercise models a load balancer, three APIs, a cache, and Postgres. After a deploy flushes the cache, the example says the database receives ten times its usual load and its 40 connections fill; a read replica is then tested against the same traffic and seed. The page reports a lower p99 for successful requests after the change, while explicitly noting that failed requests are not counted in that metric.
Observed signals
Read the marks
Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
⊠LoginAccess appeared gated
$PaidCommerce or pricing visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
ƒJavaScriptBrowser-side code central
One card from the complete issue