During the lead-up to Black Friday, I discovered a critical problem with our product quantity updates. I quickly gathered evidence and presented my findings to my boss, who acknowledged the severity of the issue and gave me the green light to find a solution.

Working alongside different teams, I devised a plan to develop a service responsible for managing all operations related to product quantity. Using MongoDB to persist the data and C# to create a web service, I focused on developing the database while a colleague tackled the web service. After extensive volume testing aside from the QA team, I’ve got nice numbers on JMeter. I found that our solution had excellent performance and could handle high volumes of requests from multiple systems.

Other teams began using our service, including those using Delphi, Visual Basic, C#, and PHP, and with everything working smoothly, we reached out to the DevOps team to deploy the solution on AWS using a high-performance server, in preparation for Black Friday.
Once again our volume tests showed nice numbers related to success rate of request and responses. The updated environment of C# and the fast response of MongoDB, a non relational database, brang powerful capabilities.

During the event, I was responsible for monitoring the product quantity functionality, which was critical for the success of the event. With full confidence in our solution, I saw 5 million requests from midnight to 11:00 a.m., with an impressive 98% success rate. Our efforts led to a successful Black Friday, and I was proud to have identified and solved the basic resource problem that had initially gone unnoticed.

Overall, I was thrilled to have played a vital role in improving the virtual store and helping the company sell millions of reais on the first day of Black Friday. The success we achieved was a true team effort, and I was proud to have been a part of it.