Apa iku feature flags lan piye hubungane karo CI/CD?

Question

Accepted Answer

**Feature flags** (feature toggles) yaiku kondisional sing mateni utawa nguripake fitur **ing runtime** tanpa deploy kode. Dheweke **misahake deployment saka release** — ngidini sampeyan deploy kode terus-terusan sambil ngontrol kapan lan marang sapa fitur beneran kapaparake, ngidini praktik delivery sing kuwat.

## Apa iku feature flags

```text
A FEATURE FLAG wraps a feature in a runtime condition:
```

```js
if (featureFlags.isEnabled("new-checkout", user)) {
  return newCheckout();      // the new feature (if the flag is ON)
} else {
  return oldCheckout();      // the existing behavior (flag OFF)
}
// → toggle the flag at RUNTIME (config/dashboard) — no redeploy needed to change behavior
```

## Misahake deployment saka release

```text
KEY IDEA: DEPLOY code (with the feature OFF) ≠ RELEASE the feature (turn it ON):
  → merge & deploy incomplete/new features safely (hidden behind an off flag)
  → RELEASE by flipping the flag — independent of deployment, instant, no redeploy
  → "deploy continuously, release when ready" → supports trunk-based development & CI/CD
```

## Kasus kanggo digunakake sing kuwat

```text
✓ GRADUAL ROLLOUT — enable for 5% → 50% → 100% of users (like canary, at the app level)
✓ INSTANT KILL SWITCH — disable a broken feature INSTANTLY (no redeploy/rollback needed)
✓ A/B TESTING — show different variants to different users; measure
✓ TARGETED release — enable for specific users/segments (beta testers, regions)
✓ TRUNK-BASED dev — merge incomplete work safely (hidden behind flags)
```

## Pertimbangan

```text
⚠️ Flags add COMPLEXITY (conditional code paths); accumulate TECHNICAL DEBT if not
   removed after a feature is fully rolled out → REMOVE stale flags
⚠️ Test both flag states; manage flags (a flag-management system for many flags)
```

## Mengapa iki penting

Pangertian tentang feature flags yaiku pengetahuan tingkat senior sing berharga amarga dheweke teknik kuwat sing **misahake deployment saka release**, ngidini praktik delivery canggih sing nambahi CI/CD, dadi kuwat kanggo delivery modern lan canggih.

Nilai inti — feature flags mbungkus fitur ing **kondisi runtime** supaya sampeyan bisa toggle dheweke on/off tanpa deploy — ngidini misahake penting **deployment saka release**: sampeyan bisa **deploy kode terus-terusan** (karo fitur sembunyine ing buri flag off, malah kalenggahan) sambil **ngontrol kapan lan marang sapa fitur beneran kapaparake** (dening mateni flag) — misahake aksi teknis deploy saka kaputusan bisnis release.

Iki ndhukung **"deploy terus-terusan, release yen wis siap"** lan ngidini trunk-based development (gabung kerjane kalenggahan aman ing buri flag).

Pangertian tentang **kasus kanggo digunakake sing kuwat** nunjukake nilaine: **gradual rollouts** (ngidini persentase pemakai sing nambah, kaya canary ing tingkat aplikasi), **instant kill switches** (mateni fitur kasaput langsung tanpa redeploy utawa rollback — mekanisme aman cepet lan berharga), **A/B testing** (ngukur varian), lan **targeted releases** (pemakai/segmen khusus, beta testing).

Iki bikin release luwih aman lan fleksibel tinimbang deployment dhewe.

Pangertian tentang **pertimbangan** — yen flag nambah kerumitan (jalur kode kondisional) lan numpuk **technical debt yen ora dibusak** sawise rollout lengkap (dadi flag lawas kudu dibersihake), lan yen loro kaadaan flag kudu diuji — nunjukake pemakaian dewasa lan tanggung jawab.

Amarga feature flags ngidini praktik delivery canggih, aman (misahake deploy saka release, gradual rollouts, instant kill switches, A/B testing, trunk-based development) sing gedhegede nambahi CI/CD, lan amarga pangertian dheweke lan trade-off yaiku berharga kanggo delivery modern, pangertian tentang feature flags yaiku pengetahuan tingkat senior sing berharga — teknik kuwat sing nambahi CI/CD dening misahake deployment saka release, ngidini delivery fitur luwih aman, fleksibel, kontrole, nunjukake praktik delivery canggih sing digunakake tim engineering dewasa.