Worked on the beast-dev/beast-mcmc repository to deliver a new parser for mixture models tree data likelihood, enhancing the system’s ability to handle complex data structures in evolutionary modeling. The work involved a comprehensive codebase refactor, including renaming classes and updating package structures to improve clarity and maintainability for future contributors. Applied skills in algorithm design, data modeling, and Java to reorganize the code and introduce the new parser, focusing on improving onboarding and code organization. No bugs were fixed during this period, with efforts concentrated on feature development and structural improvements to support advanced evolutionary modeling workflows in Java.