prod-safety-rails

prod-safety-rails

The production bounds that stop chaos from becoming the outage.

newEngine wraps an always-fire error rule with:

• WithFailureBudget(0.5, 10) — stop injecting once the error rate over the last 10 calls reaches 50%, so chaos backs off instead of taking the dependency fully down;
• WithMaxConcurrent(5) — cap simultaneously faulted calls;
• WithProductionGuard(...) — New panics if CHAOS_FORBIDDEN=1;
• WithKillSwitch(...) — all faults suppressed if CHAOS_KILL=1.

run makes 50 calls; the test asserts that some are faulted but not all — the budget engaged. Try CHAOS_KILL=1 go run . to see chaos fully suppressed.