Challenges

Real production decisions. Defend your call against a senior engineer, then get scored against an answer key. How it works

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6 of 53 challenges

Observability

6

LockedChasing a Bug: Flip Production to DEBUG and Log Everything?To catch an intermittent bug, a teammate wants to set the whole prod app to DEBUG and log full request and response bodies. Defend a safer approach.intermediate12 minintermediate12 min
LockedOn-Call Is Drowning in Alerts. Silence Them?A CPU alert pages constantly with no real impact. A teammate wants to silence it. Defend how you fix alerting properly.intermediate12 minintermediate12 min
LockedThe Queue Backlog Doubles Every Day. 10x the Consumers Tonight?A consumer queue backlog is doubling daily and a teammate wants to 10x the consumer fleet tonight. Defend diagnosing the real bottleneck first, and why blind consumer scaling can make the outage worse.intermediate12 minintermediate12 min
LockedA 30-Second Blip Became a 2-Hour Outage. More Retries?A brief downstream blip cascaded into a full-platform meltdown because every layer retried. A teammate wants to raise retry counts. Defend the real fix.advanced14 minadvanced14 min
Lockedp99 Latency Spiked Across a Microservice Chainp99 latency jumped across a request that touches six services. A teammate wants to scale up the slowest-looking one. Defend how you find the real culprit.advanced15 minadvanced15 min
LockedWe're Missing a Dimension, So Add user_id as a Label?Debugging lacked per-user detail, so a teammate wants user_id and request_id as Prometheus labels. Prometheus is already under memory pressure. Defend the call.advanced14 minadvanced14 min