Laravel New in 12: First-Class Typed Config, Slim Skeletons, and Upgrade Notes

What Actually Changed in Laravel 12

Laravel 12 is a focused release rather than a sweeping rewrite. The headline additions are typed configuration objects, a significantly slimmer default application skeleton, and a handful of helper and collection improvements. If you are running Laravel 11 on PHP 8.2+, the upgrade path is straightforward — but a few structural decisions deserve deliberate attention.

Typed Configuration Objects

The most architecturally interesting addition is first-class support for binding typed config objects into the service container. Instead of scattering config('services.stripe.key') calls throughout your codebase, you can now define a plain PHP object and register it once.

// app/Config/StripeConfig.php
readonly class StripeConfig
{
    public function __construct(
        public string $key,
        public string $webhookSecret,
        public bool $testMode,
    ) {}
}

// AppServiceProvider::register()
$this->app->singleton(StripeConfig::class, fn () => new StripeConfig(
    key: config('services.stripe.key'),
    webhookSecret: config('services.stripe.webhook_secret'),
    testMode: (bool) config('services.stripe.test_mode', false),
));

Now any class that type-hints StripeConfig receives a fully resolved, IDE-friendly object — no more string-keyed lookups, no more silent null surprises when a key is missing.

Testing Becomes Trivial

it('charges the card in test mode', function () {
    $this->app->instance(StripeConfig::class, new StripeConfig(
        key: 'sk_test_fake',
        webhookSecret: 'whsec_fake',
        testMode: true,
    ));

    // act and assert...
});

No more Config::set() scattered across test files.

The Slimmer Skeleton

Laravel 12 ships with far fewer stub files in a fresh laravel new project. Several files that previously lived in app/Http/Middleware/ are now consolidated or removed entirely, with their logic folded into the framework itself.

What is gone from the default skeleton:

• TrimStrings, ConvertEmptyStringsToNull, and PreventRequestsDuringMaintenance middleware stubs — they still run, but you no longer own copies unless you publish them.
• The app/Http/Kernel.php file is absent; middleware registration lives in bootstrap/app.php (introduced in Laravel 11, now the only way).

If your upgrade path involves a legacy Kernel.php, the migration is mechanical:

// bootstrap/app.php
return Application::configure(basePath: dirname(__DIR__))
    ->withMiddleware(function (Middleware $middleware) {
        $middleware->append(\App\Http\Middleware\MyCustomMiddleware::class);
        $middleware->remove(\Illuminate\Http\Middleware\TrimStrings::class);
    })
    ->create();

Collection and Helper Additions

collect()->intersectAssoc()

A long-requested method that compares both keys and values:

$a = collect(['color' => 'red', 'size' => 'M']);
$b = collect(['color' => 'red', 'size' => 'L']);

$a->intersectAssoc($b); // ['color' => 'red']

Str::chopStart() / Str::chopEnd()

Clean alternatives to ltrim/rtrim for specific substrings:

Str::chopStart('/api/v1/users', '/api'); // '/v1/users'
Str::chopEnd('report.csv.tmp', '.tmp'); // 'report.csv'

Upgrade Notes Worth Acting On

1. PHP minimum is 8.2. Drop any 7.x/8.0/8.1 compatibility shims.
2. Model::preventLazyLoading() is on by default in local. Audit your resources and Nova/Filament panels for N+1s before upgrading.
3. assertJsonPath now validates strict types. Tests that previously passed with loose comparisons may fail — fix the assertions, not the strictness.
4. Vite 6 is the default. If you pinned vite in package.json, bump it and review your vite.config.js for deprecated plugin options.

Key Takeaways

• Typed config objects eliminate string-keyed config() calls and make test overrides explicit.
• The slimmer skeleton reduces noise; understand which middleware moved into the framework before upgrading.
• Str::chopStart/chopEnd and intersectAssoc are small but immediately useful.
• preventLazyLoading being on by default in local is a gift — let it surface your N+1s now.
• The upgrade from Laravel 11 is low-risk if you already adopted bootstrap/app.php middleware registration.