load-testinglisted
Install: claude install-skill int2t05/engineering-skills
# Load Testing
`performance` fixes measured slowness after it appears. Load testing finds the breaking point
before users do — generate realistic and adversarial traffic, characterize how the system
saturates, and validate that autoscaling and capacity claims hold. This is proactive capacity
validation, a distinct discipline from reactive optimization.
## When to use
- Before launch: validate the system handles expected and peak traffic
- After a major change: new endpoint, architecture shift, dependency swap, data growth
- Setting or validating SLOs (p99 latency, error rate under load)
- Validating autoscaling rules and capacity headroom
- Triggers on "load test", "stress test", "capacity", "k6", "Locust", "wrk", "压测", "压力测试", "容量测试"
**Not for:** fixing a known performance bottleneck (use `performance`); unit/integration/e2e
correctness tests (use `tdd` / `api-testing` / `e2e-testing`). Load testing answers "how much can
it handle," not "does it work" or "why is it slow."
## Steps
### 1. Define capacity goals
State the targets before generating load — without them, a load test produces numbers without
judgment. Extract from SLOs, business expectations, or historical peak:
- Expected steady-state load (RPS, concurrent users)
- Peak load (2–10× steady state, sustained for how long)
- Acceptable p99 latency and error rate under target load
- The "break" threshold: the point past which the system is considered failed
_Verify: goals are written as numbers with units, not