Symfony 7 and Sylius 2.0: What Changes for Developers

Sylius 2.0 is built on Symfony 7. For developers who've been running Sylius 1.x on Symfony 5 or 6, this means a significant stack modernization. Let's break down what Symfony 7 brings to the table and what it means concretely for your Sylius projects.

Symfony 7: What's Different

Symfony 7 was released in November 2023. It's the "clean" major version that removes everything deprecated in the 6.x cycle. If you've been ignoring deprecation notices, Symfony 7 is where they become fatal errors.

PHP 8.2 Minimum

Symfony 7 requires PHP 8.2+. Sylius 2.0 pushes this to PHP 8.3. If your production servers still run PHP 8.1, you'll need to upgrade your runtime first.

This is generally a good thing — PHP 8.3 brings readonly classes, typed class constants, the json_validate() function, and significant performance improvements.

All Deprecations Removed

Every method, class, and configuration option that was marked @deprecated in Symfony 6.x is gone in Symfony 7. The most impactful removals for Sylius projects include:

• Security: The old security.encoders configuration is removed. You must use security.password_hashers.
• Mailer: SwiftMailer integration is completely gone. symfony/mailer is the only option.
• Routing: Annotation-based routing with @Route is removed in favor of PHP attributes #[Route].
• DI: Some container configuration shortcuts have been removed.

New Attributes-First Approach

Symfony 7 doubles down on PHP attributes everywhere: routing, security voters, event subscribers, DI configuration. If your Sylius project still uses YAML or annotation-based configuration for custom controllers and services, now is the time to modernize.

What This Means for Sylius 2.0

Twig Hooks Replace Template Overrides

This is Sylius-specific, not Symfony, but it's enabled by Symfony 7's component improvements. The old pattern of overriding entire Twig templates by placing files in templates/bundles/ is replaced by Twig Hooks — a system where you register small template fragments that hook into specific extension points.

The benefit: your customizations survive Sylius core updates. The cost: every existing template override needs to be rewritten.

Symfony Workflow Replaces winzou

Sylius 1.x relied on winzou/state-machine-bundle for order, payment, and shipping workflows. Sylius 2.0 uses Symfony's native Workflow component.

Key differences for developers:

• Configuration moves from winzou_state_machine to framework.workflows
• Callbacks become event subscribers listening to workflow.transition events
• Guards use Symfony's expression language instead of service callbacks
• The Workflow component has better tooling: the workflow:dump command generates visual diagrams

Symfony UX Replaces jQuery

The frontend migration isn't just a Sylius decision — it aligns with the broader Symfony ecosystem direction. Symfony UX (Turbo + Stimulus) is the official approach to frontend interactivity in Symfony applications.

For Sylius developers, this means:

• No more jQuery dependency
• Interactive features use Stimulus controllers instead of inline JS
• Page updates use Turbo Frames/Streams for partial page refreshes
• The asset pipeline changes (Webpack Encore configuration updates)

API Platform 4

Sylius 2.0 moves to API Platform 4, which brings:

• Simplified resource configuration
• Better state providers and processors (replacing data providers)
• Improved OpenAPI documentation generation
• Native JSON:API and GraphQL support improvements

If you've written custom API Platform data providers or transformers, they'll need to be updated to the new provider/processor pattern.

Practical Migration Path

Here's the approach I recommend:

Phase 1: Prepare on Sylius 1.x (1–2 weeks)

Before touching Sylius 2.0, clean up your current codebase:

1. Upgrade to the latest Sylius 1.x release
2. Run PHPUnit with SYMFONY_DEPRECATIONS_HELPER=strict
3. Fix all Symfony deprecations: encoders → password hashers, annotations → attributes, SwiftMailer → symfony/mailer
4. Make sure your tests pass green

Phase 2: Audit (1–2 days)

Run a comprehensive audit of your project to understand the full migration scope:

• Count template overrides
• List winzou state machine customizations
• Check plugin compatibility
• Inventory frontend customizations

This is where Sylius Upgrade Analyzer helps. The CLI tool automates this entire audit, scanning your codebase for all 26 migration categories and producing a report with effort estimations. It runs locally — your code doesn't leave your machine.

Phase 3: Backend Migration (1–4 weeks)

Tackle backend changes in order of dependency:

1. Update composer.json to require Sylius 2.0
2. Migrate state machine configuration and callbacks
3. Update payment gateway integrations
4. Fix any remaining deprecated API usages

Phase 4: Frontend Migration (1–4 weeks)

This can often run in parallel with backend work:

1. Replace Semantic UI classes with Bootstrap 5
2. Convert jQuery code to Stimulus controllers
3. Update asset build configuration
4. Test all interactive features (cart, checkout, admin)

Phase 5: Plugin Updates & QA (1–2 weeks)

Update all plugins, run full regression tests, and validate payment flows.

The Bottom Line

Symfony 7 + Sylius 2.0 is a major modernization. The resulting stack is cleaner, more maintainable, and better aligned with the PHP ecosystem's direction. The migration effort is real but manageable with proper planning.

The biggest risk isn't any single change — it's underestimating the combined scope. Audit first, plan methodically, and you'll come out the other side with a much better codebase.