SD-5N · Five Nines · 99.999%
Runbookly Certified System Design Architect
Proves you can keep systems running at the Five Nines level of the System design lab: you solved the level in the simulator, then built and repaired real systems in a timed practical exam, without being able to test them.
- Practice
- 4 tasks · 70 %
- Theory
- 25 questions · 30 %
- Duration
- 3 h + 2 pauses of 10 min
- To pass
- 70 % overall, 60 % in practice
- Results
- 24 hours later
- Valid
- 24 months
The exam: practice first, then theory
70 %
Practice in the simulator
4 tasks in the lab you trained in: systems to build from a brief, or to repair. Some come from the level's exercises with other data, most were written for the exam only and are never published.
During the exam you cannot run the simulation: you build or repair, then submit. After the exam our servers replay each system through its day of traffic and failures, and grade it against its objectives.
30 %
Theory
Questions on production situations and on the concepts of the level, drawn for you among the level's exercises and the certification's own bank.
You pass with 70 % overall and at least 60 % in practice: a certified engineer must make systems hold, not only know the answers.
What to master
Every concept below can be asked, and every exercise of the level becomes a scenario of the exam.
- Cloud cost optimisation
- Auto-scaling
- Caching
- Vertical scaling
- Architecture decision records
- Cell-based architecture
- Blast radius
- Multi-tenancy
- Sharding
- Bulkheads
- Capacity planning
- Elasticity
- Serverless
- Polyglot persistence
- Consensus
- PACELC
- NoSQL families
- Tunable consistency
- Monolith and microservices
- Conway's law
- Graceful degradation
- Circuit breaker
- Loose coupling
- Strangler fig migration
- Canary and blue-green releases
- Health checks