3.  Guava has one dependency that is needed for linkage at runtime:
    `com.google.guava:failureaccess:1.0.2`. It also has
    [some annotation-only dependencies][guava-deps], which we discuss in more
    detail at that link.

4.  Serialized forms of ALL objects are subject to change unless noted
    otherwise. Do not persist these and assume they can be read by a future