Even if most of MadelineProto's logic is now concentrated in the new loop and stream APIs, some parts like the TL parser are still there, albeit with many changes.
For example: now the TL parser is fully asynchronous (that may sound a bit weird to some of you, but for dynamic TL parsers, this greatly increases performances and allows parallelism).

The TL deserializer now uses yet another well-structured API called the TLCallback API to automatically populate internal databases directly on deserialization: again, this paradigm greatly reduces complexity, increases performance and is absolutely unique to MadelineProto; no other MTProto client has it, not even official clients.

One of the completely new modules that I created for MadelineProto async is the file reference database: a very complex module, required to handle files in the newer versions of the Telegram API.
It makes full use of the TLCallback API to map files to their origins, to be able to refetch them at any given time when the file reference expires.

Another new module I've implemented is the PasswordCalculator, that is used to calculate the new password hashes for the 2FA login, really cool.

I've also rewritten the APIFactory, the abstraction layer that stands between you and MadelineProto when you do $MadelineProto->method(): it is now fully async, and MUCH faster thanks to a new cached method mapping system.
The same cached method mapping system is also used for the event handler, which means that now the event handler is the fastest update management method.