Several teams consume a shared infrastructure library. An unversioned change breaks existing applications. Which practices reduce future compatibility surprises? Select 2 answers.

1. Validate representative consumer contracts and review generated infrastructure differences before promotion.
2. Delete the previous library release before consumers validate the new one.
3. Treat a passing package syntax check as proof that every existing stack remains compatible.
4. Version the shared library and make consumers adopt explicit compatible releases.
5. Force every consumer to use a mutable latest reference without testing.