---
title: Configuration
description: Config reference, YAML example, and options for Feature Flags
---

## YAML Configuration Example

```yaml title="config.yaml"
extensions:
  features:
    enabled: true
    provider: "local"                # "local", "launchdarkly", "unleash", "flagsmith", "posthog"
    refreshInterval: "30s"
    enableCache: true
    cacheTTL: "5m"

    defaultFlags:
      new-dashboard: true
      max-items: 100

    local:
      flags:
        new-dashboard:
          enabled: true
          defaultValue: true
        dark-mode:
          enabled: false
          defaultValue: false
        max-items:
          enabled: true
          defaultValue: 50
```

The extension loads config from `extensions.features` first, falling back to `features`.

## Programmatic Configuration

```go
ext := features.NewExtension(
    features.WithProvider("local"),
    features.WithRefreshInterval(1 * time.Minute),
    features.WithCache(true, 10*time.Minute),
    features.WithDefaultFlags(map[string]any{
        "new-dashboard": true,
        "max-items":     100,
    }),
)
```

## Config Struct Reference

| Field | Type | Default | Description |
|---|---|---|---|
| `Enabled` | `bool` | `true` | Enable the extension |
| `Provider` | `string` | `"local"` | Feature flag provider |
| `RefreshInterval` | `time.Duration` | `30s` | Flag refresh interval |
| `EnableCache` | `bool` | `true` | Enable flag value caching |
| `CacheTTL` | `time.Duration` | `5m` | Cache TTL |
| `DefaultFlags` | `map[string]any` | `{}` | Default flag values |
| `Local.Flags` | `map[string]FlagConfig` | `{}` | Local flag definitions |

### `FlagConfig`

| Field | Type | Description |
|---|---|---|
| `Enabled` | `bool` | Whether the flag is active |
| `DefaultValue` | `any` | Default value when enabled |

## Option Helpers

| Function | Description |
|---|---|
| `WithProvider(provider)` | Set the flag provider |
| `WithRefreshInterval(interval)` | Set refresh interval |
| `WithCache(enabled, ttl)` | Configure caching |
| `WithDefaultFlags(flags)` | Set default flag values |
| `WithConfig(config)` | Provide a complete config struct |