What is the @hasStack directive in Laravel 12.39?

The @hasStack directive allows you to conditionally render HTML elements only when a Blade stack contains content, preventing empty wrapper elements.

How do I filter routes by middleware in Laravel 12.39?

Use the new --middleware option with the php artisan route:list command: php artisan route:list --middleware=api or php artisan route:list --middleware=ThrottleRequests

What performance improvements are in Laravel 12.39?

Laravel 12.39 includes better type hints, improved caching, parallel test support, SQLite connection fixes, and enhanced exception handling.

How do I upgrade to Laravel 12.39?

Update your composer.json to require Laravel 12.39, run composer update, and check for any breaking changes in the changelog. Version 12.39 is mostly backward compatible.

Laravel 12.39: @hasStack Directive, Route Filtering & Performance Boosts

Laravel 12.39 brings focused improvements that enhance developer experience without breaking anything. The standout additions are the @hasStack Blade directive, middleware filtering for route:list, and a set of type safety and testing fixes that matter in production.

What's New in Laravel 12.39

@hasStack Blade Directive — Conditional stack rendering
Route List Middleware Filtering — Filter routes by middleware from the CLI
Type Safety Enhancements — Better PHP type hints across the framework
Parallel Test Support — WithCachedConfig now works with parallel testing
Symfony 7.4 Compatibility — Updated Request::getAcceptableContentTypes()

1. @hasStack Blade Directive

The new @hasStack directive lets you conditionally render wrapper elements only when a Blade stack has content. Before this, stacks could leave behind empty <div> or <script> wrappers even when nothing was pushed to them.

@push('scripts')
    <script>console.log('Custom script');</script>
@endpush

@hasstack('scripts')
    <script src="https://cdn.example.com/app.js"></script>
    @stack('scripts')
@endif

This ensures the CDN script tag only renders when the stack actually has content — cleaner HTML, no wasted requests.

Practical use cases

Conditional asset loading — only load Stripe.js on checkout pages
Dynamic meta tags — only render the meta block when content exists
Reusable layouts — components that gracefully handle empty slots

Real-world example: E-commerce checkout

Use @hasStack to load Stripe's JS only on pages that push to the checkout-scripts stack — keeps every other page free of unnecessary third-party scripts.

2. Route List Middleware Filtering

The route:list command now accepts a --middleware flag, letting you filter routes by the middleware they use. This is genuinely useful for security audits and debugging large applications.

# Show only API routes
php artisan route:list --middleware=api

# Show only authenticated routes
php artisan route:list --middleware=auth

# Filter by throttle middleware
php artisan route:list --middleware=ThrottleRequests

# Combine with path filter
php artisan route:list --middleware=api --path=api/v1

This is particularly useful for checking which routes are protected by authentication, auditing rate-limited endpoints, and generating API documentation from the CLI.

3. Type Safety & Performance Improvements

Enhanced type hints

ResourceCollection — $collection property is now properly nullable
Http::pool() — better type safety for concurrent HTTP operations
Exception handling — improved error message summarisation

Testing improvements

Parallel test support — WithCachedConfig now works correctly with parallel testing
Test generator — --force flag now carries through to make:test
SQLite fixes — resolved stale connection issues in RefreshDatabase

Framework integration

Symfony 7.4 compatibility — updated Request::getAcceptableContentTypes()
Factory improvements — better array cast handling
Application builder — enhanced exception handling

4. Upgrading to Laravel 12.39

The upgrade is straightforward — 12.39 is fully backward compatible. Just update your dependencies and run your test suite:

# Update Laravel framework
composer update laravel/framework

# Or update all dependencies at once
composer update

# Verify everything works
php artisan test
php artisan route:list

Check the official changelog for the full diff, though no breaking changes are expected for standard applications.

5. What's Coming in Laravel 12.40

The community is already discussing what's next. The most anticipated additions include time interval helpers for more expressive date manipulation, enhanced queue pausing/resuming, instant column additions to migrations, and PostgreSQL full-text search support. Nothing is confirmed until it ships, but these are the PRs getting the most attention.

Conclusion

Laravel 12.39 is a focused quality-of-life release. The @hasStack directive solves a real template cleanliness problem, middleware filtering in route:list improves debugging workflows, and the type safety fixes reduce runtime surprises. Worth upgrading — and painless to do so.

For more on optimising your Laravel app, see the Laravel Performance Optimization guide and REST API Best Practices.