Example 26: Failure Modes (defensive toolkit)

[patterncatalyst]

Chapter

_docs/26-appendix-m-failure-modes.md — Failure Modes

Example Path

examples/26-failure-modes/

What to demonstrate

• Taxonomy of distributed failures (partition, split-brain, partial, gray, cascading)
• Timeouts and deadlines
• Retry with backoff and jitter
• Circuit breaker states (closed → open → half-open)
• Bulkhead isolation
• Load shedding

Stack

• Infra: Podman — LGTM (chaos injection to simulate failures)
• Language: Go (sony/gobreaker + cenkalti/backoff) or Python
• Priority: HIGH — resilience patterns

Deliverables

• compose.yaml
• Service with circuit breaker, retry, bulkhead patterns
• Fault-injection helper (delay/error proxy)
• README.md
• verify.sh
• Flip chapter footer to verified