Nim 2.2.6
nim-lang.org
nim-lang.org
Thank you very much to everyone who has contributed to the development of this superior language. Nim Compiler continues to be one of the most wonderful languages I have worked with. With the speed of C and the simplicity of Python, it has allowed me to write a lot of cool software.
I do not know where I would be if Nim did not exist in my life.
So, not simple at all, then? Python is a very complex language hiding behind friendly syntax.
Do you just mean “with the syntax of Python”? Or does Nim’s similarity to Python go more than skin-deep?
Nim is much closer to Pascal / Modula / Oberon than Python. The whole - ease/simplicity of Python and speed of C is mostly marketing jargon that the Nim community has been using as long as I've been aware of the project.
In buzzword-speak, it's easy to write programs composed of nearly pure business logic while getting C++-level performance.
Given the space it's tackling I think Nim is a great effort and refreshing as it keeps a Python like syntax with a Pascal-like feel, which I feel is an underexplored evolution of languages.
this library should allow that: https://github.com/hraban/metabang-bind (never tried)
with some limitations: https://github.com/nimpylib/nimpylib/tree/master/doc/mustRew... no "end" argument in print, no triple quote and newline, no "a not in b" (write not (a in b)), no variable named _ (underscore), or double underscore, no slice as foo[:b] where the left part of the slice is not specified, rewrite foo[0:b], etc.
I characterize Nim as Python with one major difference: where Python prioritizes "developer happiness", Nim prioritized performance. As a result, the syntax looks very similar, the edges are quite a bit rougher, and performance is exponentially better.
It still "feels like" Python in a lot of ways. The ways places if differs feel a lot like Haskell IMO.
https://nim-lang.org/araq/nimony.html https://github.com/nim-lang/nimony
I suppose it very much depends on the programmer & setting, but like 3 times I've looked for Rust projects similar to Nim ones and found the performance of the Rust quite lacking. Of course, any language that allows you access to assembly makes things ultimately "only" a matter of programmer effort, but the effort to get performance out of Nim seems very competitive in my experience. I've seen at least one ancient 1990s C project be more flexible and much faster in Nim at like 6% the LOC (https://github.com/c-blake/procs for the curious).
more mature than zig, much easier than rust.
lol then i guess zig's comptime isn't a "whiz-bang-pow killer feature" either
D has a generic system similar to Nim's, and a mixin system similar to Nim's templates, but doesn't have a powerful AST-manipulating macro system like the above languages.
My guy what exactly do you think comptime is? More to the point: what exactly do you think metaprogramming is...?
Nim has a full compile time VM. You can even compile it into a program to run Nim scripts.
I don't mind but many do so I don't see this as a plus.
He is also very difficult to work with and isn't very welcoming to newcomers. The community "leaders" / moderation team is also full of abrasive individuals with fragile egos.
https://github.com/nim-works/nimskull is the hard fork I was referring to.
A hard fork with a goal of being incompatible _sounds_ more strong behaviour on the part of those who forked, than on the original language owner.
I’m sure there’s a lot of context I’m missing. But what is the story behind this?
There was a falling out between the Nim core development team and several volunteer compiler developers. The former seemed to be paying more attention to their personal projects, while still desiring to maintain their positions of control and authority over Nim and its direction. The latter group grew increasingly frustrated, the situation became extremely toxic, and ultimately Nim lost several talented compiler developers to the hard fork.
I believe the goal of being incompatible with Nim resulted from the developers involved in the hard fork feeling like the Nim development team had done a poor job of designing certain portions of the language and compiler. I'm pretty sure they ditched the C++ backend, and made some substantial changes to the langauge to bring it more inline with their ideals.
I'm not involved in the development of either project, so a much better source of information would be the Nimskull project's developers themselves and the core Nim development team.
The project has 21.5k commits authored, most of them oriented at replacing the existing compiler backend with a CPS-oriented one. Nim 3.0 is replacing the backend with one that is focused on CPS. There is no doubt that the developers responsible for the hard fork of Nim inspired Nim 3.0.
Yes, it very much is the big schism it's made out to be. I don't know what kind of activity level you expect, when the Nim language itself has few core developers working on it.
re personal compiler development playground: I don't see this for Nim 2. Nimony/Nim3 is more of a "playground", but rightfully so: he is creating a new major version of the language and aiming to improve the architecture of the compiler.
> He is also very difficult to work with and isn't very welcoming to newcomers
I don't have full context on the drama behind the fork, but I don't see Araq not being very "welcoming". Araq replies on the forums very consistently, replying to new-comer questions, which one might consider as "simple questions". Araq will state his personal & honest opinions, which may come off as abrasive or "un-welcoming" in your opinion. I don't agree with everything he says but that's OK.
From what I can tell the fork seems to be due to differences in direction of the language and w.r.t working together: differences in communication styles. But again, I don't know.
Personally, I see no reason to use the fork (Nimskull) over Nim, nor would I ever see any individual or company picking up Nimskull unless they were very deeply familiar with Nim (this is a small population of people). From a skim of the Nimskull repo, there is no website (there is a copy of the Nim manual), no forums (just some chatrooms), no clear documentation on the future direction, no documentation on differences for someone not familiar with Nim, etc. - why would anyone pick up Nimskull unless they knew Nim well? Please take this as constructive criticism. e.g. if any feature of the language/compiler/tooling is "better" or planned to be better: highlight it, summarize the long GitHub issue/projects discussions in a blog, etc.
Araq likes to work on the shiny flashy things he finds fun / interesting to work on. I'm not going to fault him for that, but things like atomics on Windows are still broken. People have been complaining about the stdlib and documentation + lack of a formal specification for at least a decade.
> From what I can tell the fork seems to be due to differences in direction of the language and w.r.t working together: differences in communication styles. But again, I don't know.
There was quite a bit of drama that caused the hard fork to materialize. Differences in communication styles is definitely describing the drama that unfolded, extremely mildly. I don't work on the fork or use it, but some of the more talented compiler developers who were previously contributing to Nim, left Nim to go work on Nimskull.
Nope. This is a sop, an equivalent to the non-apology "I'm sorry you took what I said so badly".
Aggression masquerading as "honesty" has no place in any organisation that wants to be taken seriously.
It's most certainly not "OK" when Andreas' personal opinions are expressed in ad-hominem attacks.
Nim unfortunately has a toxic Dictator at the top, and his subordinates defend his behaviours. While this continues nobody should take Nim seriously.
Araq has opinions that he defends, but you can and absolutely should try to sway or change them. I see this all the time on Discord and Forum. And I see people win over just as much as them losing.
I don't have a strong opinion if this is healthy or not, but it's probably why I would be a bad BDFL =). All in all, I don't think dictatorship is a right word here.
I can mention just exactly the same pattern with one widespreaded OS that anyone is taking seriously.
And I know one very popular and often mentioned systems programming language with "community" driven design process with inclusive and stuff which is in some kind of stagnation without BDFL (async fragmented ecosystem without C++ burden of 40 years of legacy).
Why do you think that "welcoming" is a must for successful IT projeсt?
You point to Linux but assume that Linus' infamous foul behaviour has been beneficial. This is a very basic confusion of correlation and causation.
You suggest that being "welcoming" is antithetical to "success" without defining "success".
Also, note what the "B" stands for in BDFL.
That's a charitable way to describe him. In our one direct interaction, he was condescending to the point of insult. (I believe he was incorrect as well, but even if he was always correct, I would consider it wrong to treat someone badly.) After browsing the Nim forum and issue tracker, I found that this was routine behavior for him.
Nim has some nice features, but I don't want to depend on anything that's subject to the whims of a personality like that, and I certainly don't want to interact with him again.
I certainly hope this isn't the case any longer. As one of the moderators I feel the current group is very patient and welcoming. At least that's what we're trying for, no one is perfect so I'm certain you can find counter examples. But as a whole I think we're doing pretty well. If you have any specific complaints we would love to hear them. They can be left anonymously in our community feedback form, or you can find we anywhere in the community for a chat.
But I disagree with your take on the moderation team. I don't know if you have specific names to call out, but PMunch, miran and the rest of the team have been nothing but welcoming, in my experience.
If I'm correct, I find your complaints especially about our moderators especially unfair. Arguably the only drama with moderators was in the context of Dom and you know that.
I really don't see where any of the current moderators can be described as "toxic", but you'll just say "you're one of them" anyway, so why do I even bother...
Is that for real? I bet I can find some chocolate chip cookie recipe that the Go team would disagree with me. I ain't ever using Go again.
This hasn't been my experience at all.
When I first tried Nim, years ago, I came across an inconsistency in a database connector in the standard library after only a couple of weeks. I pinged him to ask if I was understanding it correctly and confirm it was a bug. He agreed it should be updated, so I put together a pull request. It was reviewed quickly, we went back and forth a couple of times over some details, he asked me to include some documentation updates, and it was merged without issue in a couple of days in total.
Given that I came to the language as a complete newcomer and had commits to the standard library less than three weeks later with the BDFL's approval, I simply can't agree that he's difficult to work with or not welcoming.
YMMV, obviously.
I believe this and many of comments by tinfoilhatter under this post are not in good faith and in the most charitable interpretation written by a uninformed person or are severely outdated.
> Thanks for the offer, but there's a reason why Nim hemorrhages users as fast as it gains them, and a big reason for that, IMO, is the toxic community which definitely includes the moderation team.
I have to challenge this, because for the last couple years, there have been almost no incidents or drama. Moderation was almost exclusively dealing with spam messages. I think, on the forum, a couple posts were closed because of heated or offtopic discussions. But in all cases, participants were agreeing with the decision of mods (you can see them leaving a 'like' on mod's message).
> There was quite a bit of drama that caused the hard fork to materialize. Differences in communication styles is definitely describing the drama that unfolded, extremely mildly. I don't work on the fork or use it, but some of the more talented compiler developers who were previously contributing to Nim, left Nim to go work on Nimskull.
I know that some of people that left were also the ones causing problems with moderation and being toxic. I don't want anyone to draw strong conclusions, but Nim community was much healthier and friendly after the fork people and certain moderator leaving the project.
> He is also very difficult to work with and isn't very welcoming to newcomers. The community "leaders" / moderation team is also full of abrasive individuals with fragile egos.
This is just false. You can see Araq answering the noob questions on the forum all the time. He might be not the best person to do that, because his answers on the short side. I believe, noobs often need more context, examples and explanations than he's providing. But it's thought and effort that counts. Some people even hate when you treat them as complete beginner and try to nourture them common CS knowledge.
Or we could look at the project's contributor graph: https://github.com/nim-lang/Nim/graphs/contributors instead of likes on moderator's posts on the forums
> I know that some of people that left were also the ones causing problems with moderation and being toxic. I don't want anyone to draw strong conclusions, but Nim community was much healthier and friendly after the fork people and certain moderator leaving the project.
What definition of the words toxic, healthy, and friendly are you using?
> This is just false. You can see Araq answering the noob questions on the forum all the time. He might be not the best person to do that, because his answers on the short side. I believe, noobs often need more context, examples and explanations than he's providing. But it's thought and effort that counts. Some people even hate when you treat them as complete beginner and try to nourture them common CS knowledge.
Maybe if he's not the best person to do that, he shouldn't be doing it? You seem to just be playing devil's advocate here, instead of offering any real example that contradicts my claims.
As a long-time Python programmer, I was drawn to trying the language partly because of the syntax, but as soon as I tried to write something substantial, Nim's heritage in languages like Pascal, Modula, and Ada starts to show. Syntax notwithstanding, programming in it really felt more like programming in Pascal/Modula.
I in fact did not know anything about Nim's history or design choices when I started using it, but I'm old enough to have written a fair amount of Pascal, and I was not long into using Nim when I started thinking, "this feels weirdly familiar." `type` and `var` blocks, ordinal types, array indexing with enums, etc.
Why is it named proc?
Procedure used to be the common term as opposed to a function which is a mathematical entity that has no side effects. And indeed in Nim func is syntactic sugar for proc {.noSideEffect.}. Naming it def would not make sense because Nim also provides an iterator and a method keyword, whereas def stands for define.
$ tt stats
Time Tracking Stats
Total entries: 39
First entry: Oct 21, 2025 23:04
Last entry: Oct 30, 2025 18:29
Tracking since: 228h 34m
Days tracked: 5
$ tt "working on xyz today"
Logged at 11:38:44
$ tt today
Today (1 entries)
11:38:44 working on xyz today
proc groupIntoThreads(entries: seq[Entry], threshold: Duration): seq[seq[Entry]] =
if entries.len == 0:
return @[]
var sorted = entries
sorted.sort(proc (a, b: Entry): int =
if a.timestamp < b.timestamp: -1
elif a.timestamp > b.timestamp: 1
else: 0
)
result = @[]
var currentThread = @[sorted[0]]
for i in 1..<sorted.len:
let gap = sorted[i].timestamp - sorted[i-1].timestamp
if gap > threshold:
result.add(currentThread)
currentThread = @[sorted[i]]
else:
currentThread.add(sorted[i])
if currentThread.len > 0:
result.add(currentThread)Because other than them I don’t think the equivalent Python code would look much different. Maybe more concise, e.g. you could replace the second section with something like `sorted = entries.sorted(key=lambda entry: entry.timestamp)`.
Edit: Just read the second half of your post—
> I don’t think the equivalent Python code would look much different. Maybe more concise
He could be leveraging [std/sugar](https://nim-lang.org/docs/sugar.html) to make this look cleaner.
let sorted = entries.sorted(proc (a, b: Entry): int = cmp(a.timestamp, b.timestamp))
let sorted = entries.sorted((a, b) => cmp(a.timestamp, b.timestamp))
let sorted = entries.sortedByIt(it.timestamp)
proc groupIntoThreads(entries: seq[Entry], threshold: int): seq[seq[Entry]] =
let sorted = entries.sortedByIt(it.timestamp)
for i, entry in sorted:
if i == 0 or entry.timestamp - sorted[i - 1].timestamp > threshold:
result.add(@[sorted[i]])
else:
result[^1].add(sorted[i])In contrast with [], which is mostly identical to a C array: fixed size and lives on the stack.
A lot of things like this in cligen because it is a leaf dependency (the literally 1..3 identifier CLI "api") and so many "drive by" PLang tester-outers might want to roll a little CLI around some procs their working on.
Also, beyond the echo x,y is same as echo(x,y) or x.echo(y) or x.echo y, the amount of syntax flexibility is dramatically more than Python. You can have user-defined operators like `>>>` or `!!!` or `.*`. There are also some experimental and probably buggy compiler features to do "term re-writing macros" so that your matrix/bignum library could in theory re-write some bz*ax+y expression into a more one-pass loop (or maybe conditionally depending upon problem scale).
I sometimes summarize this as "Nim Is Choice". Some people don't like to have to/get to choose. To others it seems critical.
Someone even did some library to make `def` act like `proc`, but I forget its name. Nim has a lot more routine styles than Python, including a special iterator syntax whose "call" is a for-construct.
[1] https://github.com/c-blake/cligen/blob/master/cligen/print.n...
In all serious-ness, don't do that. I've used Python a lot, but Nim is a different language. Writing the proc keyword helps condition your brain to realize you are writing Nim, not Python.
If one is going to take pains to point out that there are good reasons why it is different from Python, then we can carry that as far as we like. There’s no particular reason to use indentation to denote blocks. BEGIN and END worked just fine, after all, and would be more true to Nim’s intellectual heritage. Or maybe just END, and continue to open the block with a colon.
My only complaint is that the threading/async model and how memory and GC pools are managed per thread took me a bit to get used to, but the speed and C FFI are fantastic.
Also would say that the community is very helpful, particularly on the Discord/IRC channels I have used.
One of the most recent opinions from the discord is:
“ we have async and asyncdispatch but its leaky and bug prone esp when used with threads and causes deep ownership issues, i prefer using taskman when possible but it leaves the IO problem yet unsolved ”
I’ve also been told to just use regular threads whenever possible.
Do others have more info or sentiments to share?
In some ways it's the sign of a very strong language, like the curse of Lisp: someone can easily just write their own version of whatever they need. But as a user trying to navigate the ecosystem it is frustrating. I do keep meaning to try it out again though; the language itself is very pleasant to use.
My biggest complaint about both is the lack of built-in run-time polymorphism. Rust gets you comptime and runtime polymorphism in one complete package. Nim makes use of shallow inheritance, which I find hacky, because it only lets you go one level deep. And Zig's stdlib makes it the norm to construct vtables manually, which is absolutely grotesque in my opinion. Why are we manually creating vtables in a "modern" language in 2025?