Site reliability engineering, explained.
Learn SRE through
production problems.
How systems fail, how to investigate, and how to prepare for SRE interviews. Start with a guide or try your first terminal challenge.
What is SRE? The role and engineering mindset
8 min read · Updated October 10, 2026
Beginner terminal challenge
~2 minBring the website back online
Nginx serves the website’s pages. Inspect the service, start it, then check that the website responds.
Website unavailable. Type help for commands.
curl -I http://localhost
curl: (7) Failed to connect to localhost port 80
Start typing · Enter to run · ↑ for history · Tab to complete · Browser simulation
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More guides
All articles- A Beginner's Guide to SRE7 min read
SLI vs SLO vs SLA: choosing meaningful service levels
SLI vs SLO vs SLA explained with a ticket-booking example. Learn to define what you count, write a clear objective, and work out success rates yourself.
Updated October 10, 2026Read article - A Beginner's Guide to SRE6 min read
Error budgets: balancing reliability and release velocity
SRE error budget explained with booking failures and worked percentages. Learn to calculate budget used, set a policy, and spot what the budget cannot excuse.
Updated October 10, 2026Read article - A Beginner's Guide to SRE7 min read
SRE interview practice: a reliability design capstone
SRE interview preparation capstone: plan a busy booking launch, work the error budget and capacity sums, judge a canary, and handle a growing queue.
Updated October 10, 2026Read article
Browse by topic
All articlesSRE interviews
Interview rounds, worked examples, and preparation plans for specific companies.
Editorial preview available
View guidesA Beginner's Guide to SRE
An ordered track on the SRE role, with original scenarios, 56 MCQs, and an interview capstone.
14 guides available
Explore the trackIncident response
Work through a booking failure and practise your first decisions when an alert fires.
1 guide available
View guidesTrading systems
Latency budgets, market data, and failure recovery in trading infrastructure.
First guides in preparation
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