Stateless service + k6 load test

$grit new bench-api --api
$cd bench-api

bench-api/
├── .env                       ← DATABASE_URL, JWT_SECRET, etc. live here
├── .env.example
├── docker-compose.yml         ← Postgres + Redis + MinIO for local dev
├── grit.json
└── apps/
    └── api/
        ├── go.mod
        ├── .air.toml          ← hot reload via air
        ├── cmd/
        │   ├── server/        ← main.go is here — entry point for the API
        │   ├── migrate/
        │   └── seed/
        └── internal/
            ├── config/        ← loads .env, exposes typed Config struct
            ├── database/      ← Postgres connection + AutoMigrate
            ├── handlers/
            ├── middleware/
            ├── models/
            ├── routes/
            │   └── routes.go  ← the /api/health route lives here
            └── services/

// Health check
r.GET("/api/health", func(c *gin.Context) {
    c.JSON(http.StatusOK, gin.H{
        "status":  "ok",
        "version": "0.1.0",
    })
})

# Database — Postgres (default) or SQLite
#   postgres://...        → Postgres (requires docker compose up -d postgres)
#   sqlite:./app.db       → SQLite file (no Docker, pure-Go driver)
#   sqlite::memory:       → SQLite in memory (great for tests; gone on restart)
DATABASE_URL=sqlite:./bench.db
APP_ENV=production

# Turn Sentinel (WAF) and Pulse (observability) OFF for the benchmark.
# Both sit in the request middleware chain — leaving them on means we'd be
# benchmarking them, not Gin. Re-enable them when you're done.
SENTINEL_ENABLED=false
PULSE_ENABLED=false

$cd apps/api
$go run ./cmd/server

$curl -i http://localhost:8080/api/health
$HTTP/1.1 200 OK
$Content-Type: application/json; charset=utf-8
$Content-Length: 33
${"status":"ok","version":"0.1.0"}

$mkdir -p loadtests && cd loadtests

import http from 'k6/http'
import { check, sleep } from 'k6'

export const options = {
  vus: 1,           // one virtual user
  duration: '30s',  // for 30 seconds
  thresholds: {
    http_req_failed:   ['rate<0.01'],    // <1% requests can fail
    http_req_duration: ['p(95)<200'],    // p95 must beat 200ms
  },
}

export default function () {
  const res = http.get('http://localhost:8080/api/health')
  check(res, {
    'status is 200':            (r) => r.status === 200,
    'body has "status":"ok"':   (r) => r.body.includes('"status":"ok"'),
  })
  sleep(1)
}

$k6 run smoke.js

import http from 'k6/http'
import { check } from 'k6'

export const options = {
  scenarios: {
    average_load: {
      executor: 'ramping-vus',
      startVUs: 0,
      stages: [
        { duration: '30s',  target: 50  },   // ramp to 50 VUs over 30s
        { duration: '1m30s', target: 50 },   // hold 50 VUs for 1m30s
        { duration: '30s',  target: 100 },   // ramp to 100 VUs over 30s
        { duration: '2m',   target: 100 },   // hold 100 VUs for 2m
        { duration: '30s',  target: 0   },   // ramp down
      ],
      gracefulRampDown: '10s',
    },
  },
  thresholds: {
    http_req_failed:   ['rate<0.01'],     // <1% requests can error
    http_req_duration: [
      'p(50)<50',                          // p50 under 50ms
      'p(95)<200',                         // p95 under 200ms
      'p(99)<500',                         // p99 under 500ms
    ],
  },
  summaryTrendStats: ['min', 'med', 'avg', 'p(95)', 'p(99)', 'max'],
}

export default function () {
  const res = http.get('http://localhost:8080/api/health')
  check(res, { 'status is 200': (r) => r.status === 200 })
}

$k6 run \
$  --out json=results.jsonl \
$  --summary-export=summary.json \
$  load.js

http_req_duration..............: avg=3.42ms  min=0.31ms  med=2.81ms  max=121.6ms  p(95)=7.84ms  p(99)=18.2ms
http_reqs.....................: 24812  165.41/s
iteration_duration............: avg=3.78ms
vus...........................: 100    min=0    max=100

$git add loadtests/load.js loadtests/smoke.js loadtests/report.html loadtests/summary.json
$git commit -m "perf: k6 load test — p50/p95/p99 chart of /api/health"
$git push