Freelance Programmer – Code Review & System Optimization.

Dany Tameerat is looking for a skilled Freelance Computer Programmer to perform a thorough code review and system optimization of DT Brain, the company’s integrated business management platform. This system supports various business functions such as Sales CRM, Finance, Human Resources, Payroll, Project Management, Recruitment, and Executive Reporting. The role involves identifying technical gaps, enhancing performance, addressing security issues, and implementing improvements to ensure the system is efficient, reliable, and maintainable. The successful candidate will work closely with the Chief Technology Officer on a project basis.

Key Responsibilities

Code Review & Technical Assessment
Conduct a detailed review of the existing application codebase to identify deficiencies, vulnerabilities, and inefficiencies. Provide a prioritized list of recommended fixes and upgrades to improve the system’s overall quality.

System Performance & Optimization
Detect and resolve performance bottlenecks in application pages, database queries, and background processes. Optimize database indexing and queries to enhance responsiveness without disrupting ongoing business operations.

Application Security & Reliability
Evaluate authentication methods, role-based access controls, data handling, and software dependencies. Identify and mitigate security vulnerabilities following best practices in web application security. Strengthen system stability, reliability, and data protection measures.

Code Quality & System Enhancement
Refactor and restructure code to improve readability, scalability, and maintainability. Implement necessary technical upgrades while preserving existing functionality. Recommend improvements aligned with long-term system goals.

Testing & Quality Assurance
Review current automated test coverage and ensure test suites remain effective. Develop additional tests as needed to validate improvements. Identify and fix defects introduced or discovered during optimization.

Technical Documentation & Handover
Maintain clear documentation of technical findings, modifications, and improvements. Submit a comprehensive technical assessment and completion report. Provide recommendations for future enhancements and ongoing maintenance.

Required Qualifications

Demonstrated experience in software development and maintaining web-based applications is essential. Proficiency in one or more programming languages with the ability to understand and work within existing architectures is required. Practical experience with Python, Flask, and Jinja-based applications, or the ability to quickly adapt to this technology stack, is critical. Strong knowledge of relational databases such as SQLite or SQL-based systems, including query optimization and indexing, is necessary. Familiarity with JavaScript, HTML, and CSS is expected.

Candidates should have proven expertise in code auditing, debugging, refactoring, performance tuning, and technical troubleshooting. Experience with automated testing frameworks like pytest or similar tools is important. A solid understanding of web application security principles, including authentication, authorization, and OWASP Top 10 vulnerabilities, is required. Strong analytical, problem-solving, documentation, and communication skills are essential for success in this role.

Preferred Qualifications

Experience working with ERP, CRM, finance, or enterprise business management applications is highly desirable. Familiarity with Windows-based server environments and scheduled background processes will be an advantage. Knowledge of Node.js or additional web development technologies is a plus. Prior experience independently reviewing and upgrading business-critical applications will be considered favorably.

This freelance opportunity offers a chance to contribute significantly to a vital business system, working remotely with a dynamic technology team. The role reports directly to the Chief Technology Officer and involves delivering impactful technical improvements on a project basis.