Interview questions for a site reliability engineer.
SRE is DevOps plus rigor around SLOs and error budgets. These ten test whether the candidate has internalized the discipline or only cited the book.
The questions.
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01technical medium · cicd
Design a deploy pipeline for a service that handles payments.
Strong answerBuild → test (unit, integration, contract) → staging → canary with metrics-gated rollout → full deploy. Knows when to use feature flags vs deploys. Rollback is automatic.Weak answerPush-to-main-deploys-to-prod. No canary. No rollback strategy. -
02technical medium · iac
Terraform vs Pulumi vs CDK — how would you pick?
Strong answerTeam language fluency, existing ecosystem, need for programmability, drift-detection. Not dogmatic.Weak answer'Terraform because it's standard.' Or 'Pulumi because code is better than HCL.' -
03communication medium · exec
Explain the cost of an on-call rotation to a non-technical CFO.
Strong answerConcrete dollar math — engineer hourly × expected rotations × burnout attrition cost. Knows the true cost isn't 'the pager.'Weak answer'On-call costs money.' No concrete framing. -
04situational medium · oncall-culture
Your team's on-call is burning people out. You own it. What do you change in the next month?
Strong answerReduces noise (alert hygiene). Measures toil. Redistributes load. Caps consecutive rotations. Doesn't just add more people.Weak answer'Hire more engineers.' Or 'make people tougher.' -
05technical medium · observability
What's the first dashboard you'd build for a new service?
Strong answerGolden signals — latency, traffic, errors, saturation. Per-endpoint where relevant. SLO framing.Weak answerCPU and memory. No user-facing metrics. -
06culture medium · blame
A junior engineer ran a query that took down prod for 15 minutes. How do you respond?
Strong answerBlameless. Focuses on why it was possible (no safeguards, bad tooling). Fixes the system. Reassures the engineer. Doesn't shield them from the learning.Weak answerEither fires them or coddles them. Either way, system unchanged. -
07technical hard · incident
Describe the worst production incident you've been on-call for. Timeline, what you did, what you changed afterward.
Strong answerHonest retrospective. Technical + human factors. Clear systemic change — runbook, process, or code. Names people specifically.Weak answerVague. Blames 'the old team.' No systemic change. -
08technical hard · kubernetes
You have a K8s pod that's being OOMKilled intermittently. How do you diagnose without just bumping memory limits?
Strong answerChecks actual memory usage pattern (profiler, metrics). Finds the root cause — leak, spike, burst. Considers JVM/runtime overhead. Sets requests/limits intentionally.Weak answerBumps memory. Or 'add more replicas.' -
09experience baseline · resume-probe
Your resume says you migrated from EC2 to Kubernetes. Team size, timeline, what broke?
Strong answerSpecifics. Something specific that broke (networking, secrets, state). Honest about why it took longer than planned.Weak answerParaphrases the resume. Nothing broke. -
10technical medium · security
Walk me through how you'd set up secrets management for a team of 30 engineers.
Strong answerNo secrets in repo ever. Vault / AWS Secrets Manager / SOPS. Dev gets different secrets than prod. Rotation is automated. Audit trail.Weak answer'.env files we share on Slack.' Or 'engineers memorize prod creds.'
Lucida runs round one for you, and books the shortlist on your calendar.
Adaptive interviews tuned to the role, rubric-backed scoring, and a founder-ready briefing for every candidate who clears the bar. You do the human call.