Kostas focused on improving code quality and formatting consistency in the systemd/particleos repository by implementing a configuration management policy that enforces the absence of trailing newlines in mkosi.passphrase files. Using plaintext configuration and .editorconfig, Kostas cherry-picked an upstream-aligned formatting change to standardize file structure, which reduced ambiguity and prevented CI or build failures caused by inconsistent formatting. This work did not involve bug fixes but emphasized stabilizing contributor practices and CI signals. The approach enhanced maintainability and contributor experience by establishing clear formatting conventions, ensuring that future changes would produce cleaner diffs and more reliable release processes.