Ubuntu 24.10 ships APT 2.9.8, a snapshot of the APT 3.0 development series. This already presents early versions of some of the main 3.0 topics:
New user interface
The new 3.0 user interface made its debut in the apt(8) command, providing a streamlined explanation of the changes. Sections are now separated by empty lines, the headings are shortened to be easier to skim, and finally package lists are now colored to be able to quickly judge at a glance how many packages are being removed (or installed).
Additionally, the new user interface checks if you have enough space for the updates in /usr and /boot partitions, and warns if you would exceed that space.
And finally, the new user interface replaces the single letter E/W/N tags with Error/Warning/Notice which are now translatable, making it easier to understand.
Security
APT now enforces a minimum key size of 2048 bit for RSA keys. Existing signing keys for Launchpad PPAs can be rotated using the new apt-add-repository --refresh-keys command in the software-properties-common package.
Best practices auditing
You can now pass the --audit flag to apt commands, enabling another level of error messages that highlight future deprecations or divergences from best practices. For example, this will issue diagnostics if repositories are signed with an RSA key weaker than 3072-bit, or any key type other than RSA, Ed25519, or Ed448.
New solver (early preview)
An early sneak peak of the new solver is provided, using --solver 3.0. This solver offers a new flag --no-strict-pinning allowing it to install different versions than the candidate. It is very experimental at this moment, and has some known issue in finding complex solutions: In particular, the backtracking inadvertently aborts in some cases. Error reporting is not necessarily optimal, but may already be more helpful than the current solver.