Worked on the netgrif/application-engine repository, delivering backend features focused on reliability and maintainability. Developed LDAP-backed user references by integrating the @Entry annotation into LdapUserRef, enabling seamless LDAP-based lookups when required. Enhanced Elasticsearch integration by implementing explicit scroll context management through a new clearScrollHits method and improved scroll logging. Addressed role management issues by refining import and removal processes, ensuring accurate role identification using stringId mapping and findById logic. These changes improved data integrity and startup stability. The work leveraged Java, Groovy, and Spring Boot, demonstrating a strong grasp of backend development and effective use of Elasticsearch and LDAP.