• Analysed and documented client requirements, collaborating with the onsite team.• Developed scripts to extract data from diverse websites and stored it in a MySQL database.• Transformed and prepared the data for data lakes, ensuring compatibility and consistency.• Automated ETL jobs with script-based solutions for improved efficiency.• Ensured data accuracy through validation mechanisms and indexing in MySQL tables.• Utilised reverse engineering techniques to handle JSON, Ajax, and other web technologies for efficient big data processing.• Created a Rails application to scrape data from mobile and broadband companies.• Applied object-oriented programming techniques to enhance ETL jobs in the company's Hamster product.