Feature Flags

Manage feature flags and service configurations across dev/staging/prod environments with conditional logic.

The Problem

Managing configs across environments means:

• Separate files — One config file per environment
• Duplication — Same structure repeated 3+ times
• Sync issues — Easy to miss updates in some environments

The JSSON Solution

JSSON

featureFlags [
template { feature, env, enabled }

map (flag) = {
  name = flag.feature
  environment = flag.env
  enabled = flag.enabled
  key = flag.feature + "_" + flag.env
  rolloutPercentage = flag.enabled == true ? 100 : 0
  rolloutStrategy = "gradual"
}

// New features - off in prod
"new-dashboard", "prod", false
"new-dashboard", "staging", true
"new-dashboard", "dev", true

// Stable features - on everywhere
"dark-mode", "prod", true
"dark-mode", "staging", true
"dark-mode", "dev", true
]

JSON Output

{
"featureFlags": [
  {
    "name": "new-dashboard",
    "environment": "prod",
    "enabled": false,
    "key": "new-dashboard_prod",
    "rolloutPercentage": 0,
    "rolloutStrategy": "gradual"
  },
  {
    "name": "new-dashboard",
    "environment": "staging",
    "enabled": true,
    "key": "new-dashboard_staging",
    "rolloutPercentage": 100,
    "rolloutStrategy": "gradual"
  }
  // ... more flags
]
}

Service Configuration

serviceConfig [
template { service, env }

map (cfg) = {
  serviceName = cfg.service
  environment = cfg.env

  // Database
  databaseHost = "db-" + cfg.env + ".internal"
  maxConnections = cfg.env == "prod" ? 100 : 20
  sslEnabled = cfg.env == "prod" ? true : false

  // Cache
  cacheHost = "redis-" + cfg.env + ".internal"
  cacheTTL = cfg.env == "prod" ? 3600 : 300

  // Logging
  logLevel = cfg.env == "prod" ? "error" : "debug"
}

"api", "prod"
"api", "staging"
"api", "dev"
]

Benefits

Single source — One file for all environments
Conditional logic — Different values per environment
Easy toggles — Change true to false
Consistency — Same structure everywhere

When to Use

Perfect for:

• Feature flag management
• Environment-specific configs
• A/B testing setups
• Rollout strategies

Try It!

1. Save to feature-flags.jsson
2. Run: jsson -i feature-flags.jsson
3. Manage your features!

What’s Next?

• Kubernetes — Multi-env deployments
• Overview — All examples

Toggle features with confidence! 🚀