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seanbaxter
circle
C++2019–2025
seanbaxter / circle

circle

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22Distinct people
23Mentions
0Explicit recommenders
2.6KGitHub stars
REPOSITORY AT A GLANCE

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What it is

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Where it is used

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This week on Hacker News

Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 4:00:59 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 year23 dated mentions

Observed mentions: 2019-02-22 09:47:53 UTC to 2025-12-11 11:03:13 UTC.

02462019-01-01 00:00:00 UTC to 2020-01-01 00:00:00 UTC (exclusive): 5 mentions; 5 submissions, 0 comments20192020-01-01 00:00:00 UTC to 2021-01-01 00:00:00 UTC (exclusive): 5 mentions; 1 submissions, 4 comments2021-01-01 00:00:00 UTC to 2022-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2022-01-01 00:00:00 UTC to 2023-01-01 00:00:00 UTC (exclusive): 2 mentions; 1 submissions, 1 comments20222023-01-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 6 mentions; 1 submissions, 5 comments2024-01-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2025-01-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 3 mentions; 0 submissions, 3 comments2025

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
20192019-01-01 00:00:00 UTC2020-01-01 00:00:00 UTC550
20202020-01-01 00:00:00 UTC2021-01-01 00:00:00 UTC514
20212021-01-01 00:00:00 UTC2022-01-01 00:00:00 UTC101
20222022-01-01 00:00:00 UTC2023-01-01 00:00:00 UTC211
20232023-01-01 00:00:00 UTC2024-01-01 00:00:00 UTC615
20242024-01-01 00:00:00 UTC2025-01-01 00:00:00 UTC101
20252025-01-01 00:00:00 UTC2026-01-01 00:00:00 UTC303

What Hacker News says

23 sources
MrMetric·Dec 11, 2025
Simple: A version specifier, or feature specifiers. Backward compatibility concerns vanish when I can opt-in to a newer spec. Old code keeps working, and new code doesn't suffer for legacy nonsense. For example, the Circle compiler extends C++ with its `#feature` directive: https://github.com/seanbaxter/circle/blob/master/new-circle/... Sadly, the closest I've personally seen to this sort of thing in widespread use is `"use strict";` in JavaScript, which is only a single binary switch. You can't, say, turn on a new keyword, disable a keyword, switch to a different incompatible version of some browser API, etc. I encourage all language designers to include a feature mechanism in a forward-compatible way. Don't overthink the difficulty: It doesn't need to do anything at first, it just needs to not be a parsing error. Treat it like a comment
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. FYI, this is the same as having a version number or header size in a binary file format's header, which all sane formats have (there are a lot of insane formats out there...).
In Incomplete list of mistakes in the design of CSS
aw1621107·Aug 1, 2025
> But Safe C++ and Circle are different languages, right? Eh, bit of a mixed bag, I think, depending on the context in which the words are used. "Circle" can refer to the compiler/toolchain or the set of C++ extensions the compiler implements, whereas Safe C++ is either the proposal or the extensions the proposal describe. As a result, you can say that you can compile Safe C++ using Circle, and you can also describe Safe C++ as a subset of the Circle extensions. I wouldn't exactly describe the lines as well-defined, for what it's worth. > There are presumably differences between them, and I do not know what those differences are, and I do not know if those differences were documented somewhere. They're sort of documented indirectly, as far as I can tell. Compare the features in the Safe C++ proposal and the features described in the Circl
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e readme [0]. That'll get you an approximation at least, albeit somewhat shaded by the old docs (understandable given the one-man show). > I cannot find any occurrences of "reference implementation" in the Safe C++ draft. The exact words "reference implementation" may not show up, but I think this bit qualifies (emphasis added): > Everything in this proposal took about 18 months to design and implement in Circle. [0]: https://github.com/seanbaxter/circle/blob/master/new-circle/...
In Carbon Language: An experimental successor to C++
sitkack·Feb 21, 2025
I made a facetious comment to parry that of pjmlp, whom also made a facetious comment wrt to compiler complexity and what "one person" can do. https://github.com/seanbaxter/circle It is like if one tried claiming that Fabrice Bellard was an example of a median dev. The number of C++ compilers written by one person is one. And because of this, it gives us no predictive power in what pjmlp was trying to assert. I agree with you, Albert and Lorentz and Riemann got caught in the rhetorical crossfire.
In TinyCompiler: A compiler in a week-end
mckravchyk·Sep 9, 2024
I for one started working on a new project in C++ rather than Rust. I think it's unclear whether Rust is going to be the successor at this point. It's probably never going to pick up in the games industry, QT is C++ (and Rust bindings will always be second class or they could end up unmaintained), has better compile times and is said to be undisputed when it comes to high performance. Obviously the tool for the job factor is most critical. Career wise, many people are picking up Rust and almost no one is picking up C++, while experienced C++ devs either retire or switch to a higher level language due to landscape change. I would trust supply and demand to be in favour of C++ 10 years from now. There are also attempts to make C++ more memory safe like Carbon[1] or Circle compiler [2]. If they succeed, why would anyone want to switch to Rus
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t? Also Rust is not ideal for security from a different perspective - I think the lack of a package manager is one C++ strongest points. After working for 9 years with npm, you really appreciate that the dependency you install is usually just a single dependency (even an option for a single header file is common), when there's a package manager, people will abuse it (like install a package with 3 dependencies of its own for something that could be 50 LOC copy-paste) and managing the security of the supply chain is nearly impossible (it will be a legal requirement soon in EU though). Anyway, I wanted to ask. How is the contracting market looking in C++ world? I'm guessing it depends on the domain heavily? I'm mainly asking about QT and anything that would be desktop / mobile apps / systems programming except video games, but I'm curious in general. [1] https://github.com/carbon-language/carbon-lang [2] https://github.com/seanbaxter/circle
In What's new in C++26 (part 1)
lifthrasiir·Aug 16, 2023
Context: https://github.com/seanbaxter/circle/blob/master/new-circle/... Note that Circle is not an F/OSS compiler as someone pointed out before. This however doesn't make Circle less relevant, because it is actually a testament to show that C++ could have been much better without the claimed breakage. If Circle does provide a number of desirable features and its compiler can be built by a single person, then why shouldn't the committee do the same?
In Circle Evolves C++ [video]
gavinray·Jun 23, 2023
The second someone makes a successor language that seamlessly/directly interops with C++ _AND_ has the level of build/IDE tooling that C++/Rust have, I'm on board. The closest thing right now is Sean Baxter's "Circle" compiler in "Carbon" mode IMO: https://github.com/seanbaxter/circle/blob/master/new-circle/... Unfortunately, Circle is closed-source and there's no LSP or other tooling to make the authoring experience nice.
In Making C++ safe without borrow checking, reference counting, or tracing GC
cmeacham98·Nov 10, 2022
The mod's post makes it pretty clear the primary reason for the removal is that the tweet (and reddit post title) implies the features are coming to C++, while in reality they're an extension actually coming to OP's compiler. That said, I think there's some nuance between GCC's extensions and Circle's extensions. GCC extensions are like "return the minimum of two numbers" (https://web.mit.edu/rhel-doc/3/rhel-gcc-en-3/c---extensions....), while Circle's extensions are more like "reflection in C++" (https://github.com/seanbaxter/circle/blob/master/reflection/...). GCC works with the existing C++ community and standards committees, while Circle's extensions are just the author implementing whatever random features they want. We can disagree about exactly where the line is when Circle diverges enough from C++ it deserves to be called a separa
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te language rather than just a compiler extension. And maybe you think it hasn't crossed that line yet while I do, but I don't think it's fair to claim it 100% cannot be a different language just because GCC has extensions.
In Circle is being censored from the C++ Reddit
ekelsen·May 6, 2020
I think reading through all the examples https://github.com/seanbaxter/circle/blob/master/examples/RE... makes it clear that the author has put quite a deal of thought into how these features make it easier to write clear, understandable and maintainable code. Even the example you point to goes to say: "Let's use the integrated interpreter to define a useful build tool. Software is the subject of constant revisions, and it's useful to mark a distributable with the exact version of the source-control archive it was built with." It's clear (to me) that the developer is not advocating using terminal input in the middle of a build. I haven't used terminal input since I was a child; I don't think the developer expects anyone to take that as a serious example.
In Circle – A C++ compiler with compile-time imperative metaprogramming
logicchains·May 6, 2020
>But, I think this trend might lead to extremely hard to read code, and there is a good chance that this hard-to-read code will be treated as some black box/voodoo. This already happens with metaprogramming in C++. See e.g. the source of the Boost Preprocessor library. Circle just makes this code a bit easier to read. Even code using the library: compare the compile-time Duff's device generation in https://www.boost.org/doc/libs/1_72_0/libs/preprocessor/doc/... to that in https://github.com/seanbaxter/circle/blob/master/examples/RE... .
In Circle – A C++ compiler with compile-time imperative metaprogramming

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