hardDesignCase StudyScenarioMidSeniorStaffLead
How do you decide whether to use a managed service or self-host a component, and which cloud costs catch teams out?
Managed service vs self-hosted decisions compare operational load, control, lock-in, availability and real cloud cost. The hidden costs are usually egress, cross-zone traffic, idle capacity and the team needed to run the component well. It also connects managed services to the point an interviewer is testing.
6 min readUpdated 2026-08-15
Answer
Short answer
Choose managed when it removes non-differentiating operational work such as patching, backups, failover and restore testing. Choose self-hosted only when you need control the managed service cannot provide, and include engineer time, egress and idle capacity in the cost model.
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Likely follow-ups
- You self-hosted to avoid a managed premium and it now needs a version upgrade with a maintenance window. Who owns that, and did the saving survive?
- Your architecture spans three zones for resilience and the transfer bill is now material. What would you change first?
- How would you decide whether an egress charge justifies moving a workload closer to the data it reads?
- The managed service publishes a lower availability figure than your SLO requires. What are your options?
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