GeoMesa 4.0.0 is mainly focused on upgrading dependencies and removing deprecated functionality. GeoMesa tends to be conservative with dependency upgrades, to promote stability. However, that has caused a long list of CVEs to acrue, which we have now mitigated as much as possible. GeoMesa has also added support for Java 11 and 17. These upgrades necessitated a major version bump in accordance with semantic versioning.