Worked on the alibaba/spring-ai-alibaba repository to improve the stability of OpenSearch-backed vector stores by addressing a critical bug in the builder pattern implementation. Using Java, the developer resolved an infinite recursion issue in the OpenSearchVectorStore.Builder#build method, which previously risked stack overflow during complex or large builder configurations. The solution involved replacing the recursive builder().build call with direct instantiation based on the builder’s current state, ensuring safer and more reliable construction of vector stores. This change enhanced the maintainability of the builder code and reduced production risk, leveraging skills in bug fixing, OpenSearch, and vector store architecture.