PHP legacy refactoring and Symfony refactoring without a rewrite
We refactor grown PHP and Symfony applications step by step, from PHP 5 or 7 to PHP 8 and from old Symfony versions to current ones, while the system stays in production.
The Legacy Code Challenge
Legacy PHP systems often carry the business, but over the years they collect technical debt, outdated dependencies and code nobody wants to touch. A complete rewrite is risky and expensive, and it stops new features for months.
Our PHP legacy refactoring works in small, tested steps. We put tests around the existing behaviour first, then refactor and upgrade PHP and Symfony piece by piece, so the system keeps running and new features do not have to wait.
One recent example: 15-year-old software in the medical sector, modernized while it stayed in production.
Common Legacy Challenges
Our Modernization Approach
Incremental Refactoring
Instead of risky big-bang rewrites, we use the strangler fig pattern and other incremental techniques to gradually modernize your codebase while maintaining full functionality. Each iteration delivers measurable improvements.
Safety First
We establish comprehensive test coverage before making changes, use feature flags for controlled rollouts, and maintain rollback capabilities at every step. Your business continuity is our priority.
Performance Optimization
Beyond code structure, we optimize database queries, implement caching strategies, improve algorithms, and eliminate bottlenecks to make your legacy system perform like modern software.
Knowledge Transfer
We document everything, train your team on new patterns, and establish coding standards that ensure improvements are sustainable long after our engagement ends.
The Modernization Journey
Assessment
Analyze current state, identify pain points, map dependencies
Stabilization
Add tests, fix critical bugs, establish baseline metrics
Modernization
Refactor code, update dependencies, improve architecture
Optimization
Enhance performance, scalability, and maintainability
Enablement
Train team, document patterns, establish practices
Technologies We Modernize
PHP & Frameworks
- →PHP 5.x to PHP 8.x
- →Legacy Symfony to Symfony 6+
- →Laravel upgrades
- →WordPress optimization
JavaScript & Frontend
- →jQuery to React/Vue
- →Legacy Angular to Modern frameworks
- →ES5 to Modern JavaScript
- →Build tool modernization
Backend & APIs
- →Monolith to Microservices
- →SOAP to REST/GraphQL
- →Legacy ORM updates
- →Database optimization
Infrastructure
- →On-premise to Cloud
- →Manual deploys to CI/CD
- →Legacy servers to Containers
- →Scaling improvements
Database Systems
- →Query optimization
- →Schema refactoring
- →NoSQL migration
- →Data archival strategies
Testing & Quality
- →Zero tests to Comprehensive coverage
- →Manual QA to Automation
- →Code quality tools
- →Performance monitoring
Expected Outcomes
Modern code and tools significantly accelerate feature delivery
Better code quality and testing reduce bugs and downtime
Lower maintenance costs and improved developer efficiency
Common Challenges We Solve
Legacy modernization is not a single problem. It is a cluster of interconnected problems that accumulate over time. These are the situations we encounter most often when starting a new engagement.
PHP 5 or PHP 7 still running in production
PHP 5 reached end-of-life in 2018. PHP 7.4 followed in 2022. Running unsupported versions means no security patches, no modern language features, and increasing difficulty finding developers willing to work on the codebase. We handle the full upgrade path, resolving deprecated functions, updating Composer dependencies, and adapting framework-specific code, without breaking existing functionality.
A monolith that has become too large to change safely
What started as a well-structured application gradually becomes a tangle of cross-cutting dependencies. Changing one area causes unexpected failures in another. We apply the strangler fig pattern to systematically extract bounded domains into independently deployable modules, starting with the areas that change most frequently.
No test coverage on business-critical code
Many legacy systems were built before automated testing was standard practice. Developers know which areas are risky but have no safety net when touching them. Before modernizing any module, we add characterization tests that document existing behavior. This creates a regression baseline and gives your team the confidence to refactor.
Framework version locked years behind current
Symfony 2 or 3 applications are common in companies that built their platform in the 2013-2017 period. Upgrading across multiple major versions requires a structured approach: updating one major version at a time, resolving deprecation warnings before each step, and verifying behavior through automated testing. We have done this migration path repeatedly and know where the friction points are.
Case study · B2B SaaS · Mittelstand
Symfony 2 → 7 Modernization Without a Feature Freeze
Migration of a 700k-line Doctrine 1.x codebase over 14 months with zero production downtime. Incremental strangler-fig approach with continuous feature releases throughout.
Read the case study →Ready to Modernize Your Legacy System?
Let's discuss how we can breathe new life into your codebase without disrupting your business.