Senior PHP Developer

Location: Lisbon, Lisbon, Portugal

Department: Alongside

Workplace: on_site

Employment Type: full

Description

Alongside partners with organizations to drive digital transformation and build high-performing tech teams.

We are looking for a PHP Developer to join our client’s team, an organization operating in the higher education sector, based in Lisbon.

This professional will play a key role in maintaining, optimizing, and modernizing a complex, business-critical platform that supports multiple operational areas and integrates with several internal and external systems.

The project involves working with native PHP and MySQL, contributing to the modernization of legacy applications, improving system performance, and supporting the migration to more recent technology versions.

Responsibilities

• Maintain, develop, and optimize business-critical applications using native PHP and MySQL.
• Contribute to the modernization of legacy systems, including migration from PHP 5 to PHP 8 and MySQL 5 to MySQL 8.
• Analyze existing codebases, understand complex business logic, and identify opportunities for architectural improvements.
• Develop, maintain, and troubleshoot integrations with multiple internal and external systems, including ERP platforms.
• Ensure application stability, security, scalability, and performance.
• Optimize database queries, connections, and processes to support high volumes of data and concurrent users.
• Investigate and resolve performance bottlenecks and technical issues in legacy applications.
• Support the maintenance and improvement of backend services, web applications, and internal management platforms.
• Document existing functionalities, integrations, and technical processes.
• Collaborate with internal stakeholders to define technical solutions and modernization strategies.
• Ensure business continuity throughout migration and modernization activities.

Requirements

• At least 5 years of professional experience in PHP development, ideally in complex enterprise environments.
• Strong hands-on experience with native PHP, without relying exclusively on frameworks such as Laravel or Symfony.
• Solid experience with MySQL, including database optimization, query performance, and connection management.
• Proven experience maintaining, troubleshooting, and modernizing legacy applications.
• Experience working with complex integrations between different systems, APIs, and databases.
• Strong understanding of software architecture, object-oriented programming, and backend development principles.
• Ability to understand and maintain large, complex, and poorly documented codebases.
• Experience identifying and resolving performance and scalability issues.
• Strong analytical and problem-solving skills.
• High level of autonomy, ownership, and technical decision-making capabilities.

Nice to have

• Previous experience migrating applications from PHP 5 to PHP 8.
• Experience upgrading MySQL databases from older versions to MySQL 8.
• Experience integrating applications with SAP or other ERP systems.
• Knowledge of Linux environments and server administration.
• Experience with high-volume data processing, synchronization, and scheduled background jobs.
• Knowledge of database connection pooling and performance optimization.
• Experience working with systems involving multiple interconnected business modules.
• Familiarity with technical documentation and legacy code refactoring.

Benefits

• On-site: Lisbon
• Opportunity to work on a long-term project within the higher education sector.
• Direct involvement in the modernization of a complex and business-critical platform.
• Opportunity to contribute to technical and architectural decisions.
• Challenging technical environment with significant impact on daily operations.
• Stable project with long-term collaboration opportunities.