php 36 lines · 6 steps

Defining feature flags with Laravel Pennant

A service provider registers feature flags at boot, from simple config toggles to per-user gradual rollouts.

Explained by highlit

Laravel Intermediate feature-flags service-provider config-driven gradual-rollout closures

1<?php
2 
3namespace App\Providers;
4 
5use App\Models\User;
6use Illuminate\Support\Lottery;
7use Illuminate\Support\ServiceProvider;
8use Laravel\Pennant\Feature;
9 
10class FeatureServiceProvider extends ServiceProvider
11{
12    public function boot(): void
13    {
14        foreach (config('features.simple', []) as $feature => $enabled) {
15            Feature::define($feature, fn () => (bool) $enabled);
16        }
17 
18        Feature::define('new-billing', function (User $user) {
19            if (in_array($user->email, config('features.new_billing.allowlist', []))) {
20                return true;
21            }
22 
23            return match (true) {
24                ! config('features.new_billing.enabled') => false,
25                $user->onTrial() => false,
26                default => Lottery::odds(
27                    config('features.new_billing.rollout_percent', 0),
28                    100,
29                ),
30            };
31        });
32 
33        Feature::define('beta-dashboard', fn (User $user) => $user->hasVerifiedEmail()
34            && $user->created_at->lt(config('features.beta_dashboard.cutoff')));
35    }
36}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Feature flags belong in a provider's boot method so they're registered once and resolved lazily on demand.
2Driving flag values from config lets you flip features without touching code or redeploying.
3Percentage rollouts and allowlists let you ship risky features to a controlled slice of users first.

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