1: Service to Library Migration(Dependency Injection Library):∗ Developed the HLD, LLD, and executed a Spring Boot service migration to Library using custom DIlibrary. This custom dependency injection minimized runtime processing & jar size.∗ Our DI library was a combination of compile time and runtime processing.I kept minimal reflection apiusage & leveraged annotation processing at compile time for resolving DAG. Impact:∗ Leveraged DI with the given constraints, improved the memory consumption during runtime by 2 % .∗ Reduced the startup time by breaking the DI into compile time & runtime processing , achieved detection of invalid class dependency at compile time.2: Journey Gamification:We developed a project to boost customer retention by nudging users to adopt high-value actions on the platform. My responsibilities revolved around coming up with LLD & execution of modules interacting with database.Impact: Scaled the system for 40 million users, achieving 32% adoption rate and increasing GMV by 350crore.3: Supercoin redemption algorithm:Revamped the cash and coin algorithm for supercoin distribution, integrating a cart fee based on coin balance. The task involved complex algorithm which used dynamic programming and binary search concepts.Impact: Increased burn/earn ratio of coin.Reduced coin wastage .4: Oncall bugs:*Identified one of our major service database metrics we were getting dropped & fixed the bug , the delta in metrics was around 34k .* Identified and resolved a function bug for journey gamification service. Reduced customer escalation by 9 %.* Identified a critical bug related to sync call between two of our service , made them asynchronous & reduced the escalation by 11% , failure rate 25 %.