A library whose API is unchanged from years ago, has improved security, and complies with modern and much discussed non-ambiguous specifications. Using version 0.3.16 as a baseline, there will be: No API changes (output changes to match specifications do not count as part of the API), no new features, and no deprecated features. No known security issues. No known issues processing CommonMark and GitHub Flavored Markdown specifications (without reason). Deprecation strategy and identified features to deprecate. Improved foundation of community standards, project maintenance processes, and tooling (make it easier to keep marked from going stale again).