Worked on the marimo-team/marimo repository to address a serialization issue affecting Matplotlib Figure objects in the msgspec encoder. Focused on backend development and data visualization, the solution involved HTML-encoding Figure data to match the existing approach for Axes, ensuring consistent and correct rendering in exports and dashboards. The work was implemented in Python, with comprehensive tests added to cover edge cases in Figure serialization. Documentation and API references were updated to reflect the new encoding behavior, supporting long-term maintainability. This targeted bug fix improved the reliability of figure rendering across analytics pipelines and reduced related runtime errors.