Will support:

- transient keyword
- externalizable, although plain serialization will be faster in most of the cases as this will cause extra overhead
- private methods for writeObjects (This used to be in the list of will not support)


May support:

- class versioning (may make optional)
- Do we need to support dynamic proxies?

Will not support:

- If an externalizable class write stuff in different orders we won't support it. Keep in mind that Integers and Longs are stored as primitive types first, them converted to native


Documentation:

- Avoid using ByteArrayOutputStream. If need a temporary repository or cloning use DataOutput instead.