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python
mypy
Python2013–2026
python / mypy

mypy

Optional static typing for Python

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Explore on GitHubRead Hacker News discussions
81Distinct people
96Mentions
1Explicit recommenders
20.7KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Optional static typing for Python

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

PEP 695 is great. I've been using mypy every day at work in last couple years or so with very strict parameters (no any type etc) and I have experience writing real life…

gnulinux used a recommendation phrase. One indexed comment matches. This is a phrase match, not a verdict.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

Mentioned in the same Hacker News threads. That is not proof they are substitutes.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 6:01:08 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by year96 dated mentions

Observed mentions: 2013-07-08 20:54:16 UTC to 2026-03-17 14:56:14 UTC.

0510152013-01-01 00:00:00 UTC to 2014-01-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 comments20132014-01-01 00:00:00 UTC to 2015-01-01 00:00:00 UTC (exclusive): 2 mentions; 2 submissions, 0 comments2015-01-01 00:00:00 UTC to 2016-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2016-01-01 00:00:00 UTC to 2017-01-01 00:00:00 UTC (exclusive): 5 mentions; 2 submissions, 3 comments2017-01-01 00:00:00 UTC to 2018-01-01 00:00:00 UTC (exclusive): 6 mentions; 0 submissions, 6 comments2018-01-01 00:00:00 UTC to 2019-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 15 mentions; 0 submissions, 15 comments20192020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 17 mentions; 1 submissions, 16 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 10 mentions; 1 submissions, 9 comments2022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 9 mentions; 0 submissions, 9 comments2023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 11 mentions; 0 submissions, 11 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 8 mentions; 1 submissions, 7 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 7 mentions; 0 submissions, 7 comments2026-01-01 00:00:00 UTC to 2027-01-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments. Incomplete calendar period.2026*

* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
20132013-01-01 00:00:00 UTC2014-01-01 00:00:00 UTC110
20142014-01-01 00:00:00 UTC2015-01-01 00:00:00 UTC220
20152015-01-01 00:00:00 UTC2016-01-01 00:00:00 UTC101
20162016-01-01 00:00:00 UTC2017-01-01 00:00:00 UTC523
20172017-01-01 00:00:00 UTC2018-01-01 00:00:00 UTC606
20182018-01-01 00:00:00 UTC2019-01-01 00:00:00 UTC202
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC15015
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC17116
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC1019
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC909
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC11011
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC817
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC707
2026 (partial)2026-01-01 00:00:00 UTC2027-01-01 00:00:00 UTC202

What Hacker News says

15 sources
m_ke·Dec 28, 2019
You should check this out: https://www.youtube.com/watch?v=Z8vsTxzmorE https://openteams.com/initiatives/2 > "We will create an embedded domain specific language (DSL) using the Python language itself along with the typing module and specialized objects as necessary to allow nearly all the existing extensions to be written using this DSL. We will then port several key libraries such as NumPy, SciPy, and Pandas to use this DSL. We will also provide a runtime so these extensions can work on PyPy, C-Python, and RustPython." I'm pretty sure we'll see a strict, typed subset of python that is jitted or compiled at some point in the next few years. Edit: Oh also mypyc https://github.com/python/mypy/tree/master/mypyc
In Python Type Hints
Rotareti·Nov 29, 2019
> The 2/3 mess (yes it is still a thing) It's still a thing for the (loud) few who couldn't manage to move to 3 after 10 years. The rest just went on. The ecosystem is on 3 [0] and it has been for years now. [0]: http://py3readiness.org/ > The insane packaging situation. Packaging a Python app is a nightmare. The packaging story in Python is in the middle of a big transformation from legacy tools to modern npm/yarn/cargo-like tools. pipenv [1] and poetry [2] are the most popular contenders. It will take a while until the community settles on this, but both tools work already. [1]: https://github.com/pypa/pipenv [2]: https://github.com/sdispater/poetry > Dynamically typed Python 3.5 introduced type annotations. It is now possible to write statically typed code in Python via mypy [3], which from my experience works similar well as TypeScrip
Read the rest
t works for JavaScript. [3]: https://github.com/python/mypy
In My 2019 programming language hierarchy
Rotareti·Sep 19, 2019
You can write Python like pseudo-code. Sometimes the results look almost like plain English. For example, if I have to design software for a micro-controller that uses C/C++ I sometimes write down the algorithm in Python (with editor support: auto-formatting, etc.), then I implement it in C/C++. There is no better way to write pseudo-code that I know of. Python is also great to create a prove of concept for something. It allows for rapid prototyping due to the simple syntax, the high-level features, the huge ecosystem and the dynamic type system. Most of the time the result is good enough for production. You can add type annotations and get statically typing via mypy [0] to harden the code base. This works really well. (See: JS->TypeScript). Python has a well developed FFI which allows you to call C/C++/Rust, without large performance hit
Read the rest
s. I think this is one of the main reasons for Python's success. It can be used as a high level interface to a huge low level ecosystem. ML wouldn't exist in Python without that. Python is a great language to create simple scripts as well. I use it as a bash replacement. But beware: Python can get really ugly if you rely too heavily on OOP/Inheritance. There is a lot of ugly Python code out there. I think Python shines the most if you use it in a procedural/semi-functional style and describe data-types for your business logic (almost) entirely with (dump) dataclasses [1] and namedtuples [2]. Beware2: Python's packaging story (package manager, etc) is currently in a messy state. There are good solutions, but it's difficult to find the right tools for a newcomer. I think it will take a couple of years for the dust to clear, but you might want to check out pipenv [7] or poetry [8] These packages will make your life a lot easier. I use them for every project: - black [3] or yapf [4] (auto-formatter) - mypy [0] (statically typing with editor support for VSCode) - pylint [5] or flake8 [6] (linter) [0] https://github.com/python/mypy [1] https://docs.python.org/3/library/dataclasses.html#module-da... [2] https://docs.python.org/3/library/typing.html#typing.NamedTu... [3] https://github.com/psf/black [4] https://github.com/google/yapf [5] https://github.com/PyCQA/pylint/ [6] https://github.com/PyCQA/flake8 [7] https://github.com/pypa/pipenv [8] https://github.com/sdispater/poetry
In Python Is Eating the World
meowface·Sep 16, 2019
Python supports optional static typing annotations now. There are four popular typecheckers that I'm aware of (mypy [1], pyre [2], pyright [3], pytype [4]), which is a little confusing, but any of the four will catch a lot of type issues that typical statically typed language compilers would catch. It's not as robust as true static typing - there are sometimes false positives and false negatives - but I find it helpful. [1] https://github.com/python/mypy [2] https://github.com/facebook/pyre-check [3] https://github.com/microsoft/pyright [4] https://github.com/google/pytype
In The boring technology behind a one-person Internet company (2018)
neuland·Jun 12, 2019
Hey, thanks a lot for pointing this out! Yet another reason to use data classes vs. named tuples. Looks like just plain class level attribute declaration also works: class Node: child: 'Node' I wonder why `typing.NamedTuple` is unique as far as it not working. I know they don't use `eval` and templating to create it anymore. From looking at the code [0], they're using metaclass / __new__. But other than the fact that it uses metaclasses, I'm not sure why it'd have an error. Obviously there's cycle handling in mypy, otherwise none of the examples would work. If I use an example with a metaclass, that also typechecks. So, it's not metaclasses that trigger the error. class NodeBase(type): def __new__(cls, name, bases, attrs): return super().__new__(cls, name, bases, attrs) class Node(metaclass=NodeB
Read the rest
ase): child: 'Node' # works Edit: it looks like there is now work going into this and other cases where recursive types don't work [1][2]. For example: `Callback = typing.Callable[[str], Callback]` and `Foo = Union[str, List['Foo']]`. [0] https://github.com/python/cpython/blob/3.8/Lib/typing.py#L15... [1] https://github.com/python/mypy/issues/731 [2] https://github.com/python/mypy/issues/6204
In A Failed Experiment with Python Type Annotations
Rotareti·Mar 24, 2019
As someone who works full time in Python and TypeScript, I find the typing experience quite similar in both languages. You can be "productive" in both languages "in medium-to-large-sized projects". > Mypy mostly seems immature, buggy ... That was my experience some time ago as well, but it's getting better from release to release. Look at the repo [0], it's continuously improving. I find Mypy deserves more recognition. The same guys working on mypyc [1], which I think is very interesting too. [0]: https://github.com/python/mypy/graphs/contributors [1]: https://github.com/mypyc/mypyc
In On Learning Rust and Go: Migrating Away from Python

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