Nearly twenty years after the first igraph release, igraph 1.0 has finally arrived. This release focuses on providing a stable and more consistent interface that users and downstream maintainers can rely on with confidence, as well as adding new features that required API-breaking changes. There is now an official versioning policy, see VERSIONING.md.
This is a companion discussion topic for the original entry at https://igraph.org/2025/09/20/igraph-1.0.0-c.html