Core System & Module Development

• Write clean, maintainable code (PHP for backend, React/TypeScript for frontend).
• Design and build custom backend modules, custom database entities, and custom UI components.
• Refactor legacy code to improve application speed, memory usage, and database query performance.

API Architecture & Integration Engineering

• Build, secure, and maintain RESTful or GraphQL APIs for external application consumption.
• Write custom webhooks and backend middleware to connect the CRM with external microservices, payment gateways, or ERPs.

Bug Fixing & Security Maintenance

• Review, reproduce, and resolve critical bug reports logged by users, specialists, or community members.
• Audit code for security vulnerabilities (e.g., SQL injection, XSS, authentication leaks) and apply security patches.

Database Design & Migration

• Structure relational database schemas (MySQL, PostgreSQL) to support high transaction volumes.
• Write database migration scripts for system updates without causing data loss or downtime.

Code Review & Open-Source Governance

• Review and merge Pull Requests (PRs) submitted by third-party community developers.
• Write unit tests, integration tests, and maintain CI/CD pipelines to ensure release stability.