jdarcy

I've commented a few times about some issues I see with the scalability of ActivityPub - the protocol behind the Fediverse and its best-known implementation Mastodon. A couple of folks have asked for more elaboration, so ... here it is.

First, let me add some disclaimers and warnings. I haven't devoted a lot of time to looking at ActivityPub, so there might be some things I've misunderstood about it. On the other hand, I've brought bigger systems - similar node counts and orders of magnitude more activity per node - from broken to working well based on less study of the protocols involved. So if you want to correct particular misconceptions, that's great. Thank you in advance. If you want to turn this into an appeal to authority and say that I'm wrong only because I haven't developed a full ActivityPub implementation or worked on it for X years ... GTFO.

What

What is ActivityPub? It's an HTTP- and JSON-based protocol for exchanging information about "activities". An activity could be many things.

dabeaz

# Author: David Beazley (https://www.dabeaz.com)
# Twitter: @dabeaz

from functools import reduce
run = lambda s: reduce(lambda *_:..., iter(lambda s=[s]:
                      (_:=s.pop()(),s.append(_))[0], None))

const   = lambda v,c   : lambda: c(v)
add     = lambda x,y,c : lambda: c(x+y)
mul     = lambda x,y,c : lambda: c(x*y)

rhettinger

'Emulate max() as fully as possible in pure Python.'

# https://stackoverflow.com/questions/69997857/implementation-of-max-function-in-python/69997876#69997876
# https://github.com/python/mypy/issues/7231

from typing import TypeVar, Any, Iterator, Iterable, Optional
from typing import Union, Protocol, Callable, cast, Tuple, overload


class SupportsGT(Protocol):

ctokheim

Cython

Cython has two major benefits:

1. Making python code faster, particularly things that can't be done in scipy/numpy
2. Wrapping/interfacing with C/C++ code

Cython gains most of it's benefit from statically typing arguments. However, statically typing is not required, in fact, regular python code is valid cython (but don't expect much of a speed up). By incrementally adding more type information, the code can speed up by several factors. This gist just provides a very basic usage of cython.

fperez