Freelance Programmer – Code Review & System Optimization.

Dany Tameerat is looking for an experienced Freelance Computer Programmer to perform a thorough technical review, optimization, and enhancement of DT Brain, the company’s integrated business management system. DT Brain supports various business functions such as Sales CRM, Finance, Human Resources, Payroll, Project Management, Recruitment, and Executive Reporting. The ideal candidate will have strong programming skills and proven experience in reviewing existing codebases, identifying technical gaps, resolving performance and security issues, and implementing sustainable improvements to boost system efficiency, reliability, and maintainability.

Key Responsibilities

Code Review & Technical Assessment: Conduct a detailed review of the current application codebase to identify technical deficiencies, vulnerabilities, inefficiencies, and areas for improvement. Provide a prioritized list of recommended fixes and upgrades.

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

Application Security & Reliability: Evaluate authentication mechanisms, role-based access controls, data handling, and software dependencies. Identify and address potential security vulnerabilities following established web application security standards. Enhance system stability, reliability, and data protection.

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

Testing & Quality Assurance: Review existing automated test coverage to ensure test suites remain functional. Develop additional tests as needed to validate system improvements. Identify and resolve defects discovered during the optimization process.

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

Required Qualifications

Demonstrated professional experience in software development, programming, and maintenance of web-based applications. Strong proficiency in one or more programming languages with the ability to understand and work within existing application architectures. Practical experience with Python, Flask, and Jinja-based applications, or the ability to work effectively with this technology stack. Solid understanding of relational databases, including SQLite or SQL-based systems, query optimization, and indexing. Working knowledge of JavaScript, HTML, and CSS. Proven expertise in code auditing, debugging, refactoring, performance optimization, and technical troubleshooting. Familiarity with automated testing frameworks such as pytest or equivalent tools. Understanding of web application security principles, including authentication, authorization, and OWASP Top 10. Strong analytical, problem-solving, documentation, and communication skills.

Preferred Qualifications

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

This freelance, project-based role reports directly to the Chief Technology Officer (CTO) and offers an opportunity to contribute significantly to the optimization and future-proofing of a critical business system.