alt.hn

6/2/2026 at 7:56:46 PM

My thoughts after using Clojure for about a month

 https://www.acdw.net/clojure/

by speckx

6/3/2026 at 10:27:03 AM

> "I do wish there were an easier way to move in the ]}]})))}-ness of block ends though."

If he means navigating the AST, there is Parinfer: https://shaunlebron.github.io/parinfer/

Paredit / Parinfer ruined other languages for me. It lets you navigate up/down/in/out of the Clojure AST with keyboard commands and mutate those expressions, e.g. "Split" will split open the current data structure you're in: `(a| b)` =Split=> `(a)| (b)`, where | is caret. Join is the inverse, and it works for all data structures.

by pgt

6/3/2026 at 3:11:02 PM

I type out nowhere near enough code for this to matter, but it's pretty cool nonetheless!

by stodor89

6/3/2026 at 11:27:55 AM

Indeed. The incredibly clumsy way we choose to edit source code has baffled me since I was first acquainted with parinfer. Having to keep the source in the shape of a valid AST almost entirely manually is really annoying.

by Sharlin

6/3/2026 at 3:29:37 PM

Syntax-directed editors were all the rage in the late 70s early 80s...and a huge failure, because they were a lot more annoying than any text editor has a chance of ever being.

It's one of those things that, like visual programming, is absolutely and obviously The Right Thing™ until you try to implement it and use it.

That said, we have made progress in both areas, and maybe we will figure them out in the future.

by mpweiher

6/3/2026 at 12:08:36 PM

Check out Ki editor https://ki-editor.org/ — core movements based on AST

by evelant

6/3/2026 at 12:42:51 PM

Huh, very interesting and obvious in hindsight. What languages/syntaxes does it support though? Parinfer is lucky that it's relatively small amount of syntax, so can work for entire languages with relative ease, but how does Ki Editor work with Rust for example, if it does? Special keybindings per language?

by embedding-shape

6/3/2026 at 12:47:48 PM

Looks like it’s written in Rust and the examples are also in Rust :) Apparently it supports any language with a tree-sitter parser, which makes sense, tree-sitter is basically made for this.

by Sharlin

6/3/2026 at 12:57:23 PM

Hmm, but how does that work in practice? Silly and small example; adding/remove turbofish, is very Rust specific, I can't imagine that to be generalized across all tree-sitter parsers, or I misunderstand how tree-sitter is used here, but how would you add/remove/move around Rust's turbofish for example?

by embedding-shape

6/3/2026 at 2:58:23 PM

This is borderline silly, though. It is clumsy to start. But so is walking. As is running. Have you seen people start out on bicycles? What about writing? Talking?

That is to say, all things start out clumsy. And people that are good at it, no longer feel that it is clumsy. Which is why a lot of people that have been working with this for any time just don't think of this much.

by taeric

6/3/2026 at 4:46:51 PM

Such a strange attitude.

If a tool is clumsy, we try to improve it, that has been the case since the first stone artifacts created a million years ago.

Do you think that the (sort of) tree-based affordances that most modern code editors do support, like autoindentation and brace pairing/enclosing, are silly too? What about some slightly more advanced features, like the AST-based "extend selection" and "move statement up/down" features in JetBrains IDEs?

Or do you think that the status quo just somehow happens to be exactly right and going any further would be silly?

by Sharlin

6/3/2026 at 5:05:58 PM

It would be silly strictly for how strongly worded it is. I should also say that there is nothing wrong with being silly. Someone may actually come up with something some day that meaningfully changes us here.

That is, I am not disagreeing that it can be a little bit clunky. But, a lot of the power that experienced users have in reading code is specifically that they have built a bit of automaticity in reading it. That is, the clunky aspects of fixing it is something you pretty much have to do. You just build speed at automatically doing it rapidly.

So, the status quo is to use the helper functions that you want to use. But usually after you get the experience in the clunky phase.

by taeric

6/3/2026 at 2:11:12 PM

In the blind community, navigation by indent level is pretty popular, no idea why it hasn't caught on anywhere else.

I find it a nice middle ground between the craziness of vim and the slowness of traditional cursor usage.

by miki123211

6/2/2026 at 10:04:02 PM

> I am now generating this website with Clojure

As everyone knows, you are not a true lisper until you have written your own static site generator.

It gave me such a great high with how easy it was to add my own "templating engine" on top, implemented all using macros. The downside is that the crash came hard; there is so much more to a good static site generator such as optimizing the output, supporting scoped CSS, server-side rendering of SPA framework components, and of course integration with the Node ecosystem (for better or for worse there is just so much useful stuff). I have since moved over to Astro. It's still fascinating how far I was able to push my own SSG all by myself though.

by HiPhish

6/2/2026 at 10:20:04 PM

Heh, inspired by hiccup, I ended up implementing my favorite Clojure templating library but in Nix, exactly for the purpose of static site generation :) Even have a nifty demo of how it looks for that, it basically looks/works the same as hiccup: https://emsh.cat/niccup/examples/blog/

by embedding-shape

6/2/2026 at 11:42:25 PM

This is awesome, thanks for sharing

by tymscar

6/3/2026 at 7:16:57 AM

Funny, learning Janet I exactly did that. Was quite a fun experience with the built-in PEG, so I did markdown parsing from scratch. Maybe eventually I will be a true lisper (fell in love with Scheme over 20 years ago but could never really use any lisp professionally. Now I at least do some small things in Clojure and babashka. I love babashka)

by fp64

6/3/2026 at 3:19:33 AM

Oh I've written an SSG in multiple variations of lisp, as well as sh, make, and most other languages I toy around with. It's been a good "kick the tires" project but I think I need a new one.

by acdw

6/3/2026 at 2:23:53 AM

Yeah integrating NPM is the big one, then you’re whole day converts to recovering from breaches

by tmpz22

6/3/2026 at 9:19:50 AM

> As everyone knows, you are not a true lisper until you have written your own static site generator.

I think that part is quite normal. I use ruby for the same purpose, though the only difference is that the code I use is also to be used for dynamic websites at the same time (cgi, rack, sinatra, in theory ruby on rails but I just can't stand rails and DHH these days, so I am in the opposition crowd). Using static websites, though, always feel as if I have significantly less flexibility. I do generate some static .html files as well, but they feel less useful to me, aside from being displayed faster, of course.

by shevy-java

6/3/2026 at 12:39:43 AM

Once you learn Clojure's syntax and semantics, you're no longer bound to the JVM. There's ClojureScript (JS), ClojureCLR, ClojureDart, jank (C++), Basilisp (Python), babashka (SCI), and many others. This means that, if you don't know Java or don't like the JVM, you can likely use Clojure wherever you already feel most comfortable.

For the most part, any Clojure code which doesn't use host interop will work on all dialects. Clojure also has support for conditional code, depending on the current dialect.

This is one of Clojure's superpowers.

by Jeaye

6/3/2026 at 3:27:07 PM

> babashka (SCI)

Correct me if I'm wrong, but isn't babashka's "host"... um.. "native", for lack of a better word? It's compiled with Graal VM native, no?

Yes, there is SCI (Small Clojure Interpreter) in the middle, but that's beside the point, no?

https://github.com/babashka/babashka

https://github.com/babashka/sci

by JBiserkov

6/3/2026 at 4:41:48 PM

Babashka's interop is with Java, since Babashka uses a Graal-compiled version of the JVM. It's still the JVM, just baked down.

This is different from interop with the native world. It's different from the host runtime actually being native, rather than a baked down version of a whole VM.

Graal's native images blur the line between the JVM and native, I would not say Babashka has a native runtime. Perhaps borkdude would disagree. Might be an interesting discussion.

by Jeaye

6/3/2026 at 5:13:35 AM

As someone who loves Clojure, I wonder about the real portability across host languages. Do you have experience with any of these other dialects? (beyond the obvious CLJS & Babashka?)

by Hammershaft

6/3/2026 at 6:17:39 AM

I am developing a test suite for portability of clojure.core across dialects. You can find it here: https://github.com/jank-lang/clojure-test-suite

Currently, we have Clojure, ClojureScript, ClojureCLR, Babashka, Basilisp, Phel, and jank running the test suite.

I have only used Clojure, ClojureScript, and Babashka in production. But I am the creator of jank.

by Jeaye

6/3/2026 at 3:35:51 AM

for JS there is also Squint which is a light-weight ClojureScript dialect without the Google Closure Compiler

by brazukadev

6/3/2026 at 3:30:28 PM

indeed, light-weight means you just add a <script> and you're off to the races.

There's also nbb if you're targeting node https://github.com/babashka/nbb

by JBiserkov

6/2/2026 at 10:17:28 PM

With respect, this topic in particular has been beaten to death.

I too liked Clojure when I tried it some years ago (agreed on the composition and data structures; both are _great_). But the real value-add is in the runtime, not the syntax. Java has a solid runtime but it's not yet as good as Erlang's, maybe even not up to the standards of Golang -- I am talking concurrency / parallelism here (for memory management I have no doubts Java is very good). And I know: green threads and stuff. Well, call me when you can do what Erlang / Golang can do. Then I'll look again, very seriously too.

Programming language syntax scarcely matters. It does to some extent but we the programmers tend to over-romanticize it. The runtime and its properties are the much better thing to optimize for.

by pdimitar

6/3/2026 at 2:08:47 AM

Clojure is about its rigorous and pragmatic "immutability first" paradigm that you simply don't get from other PLs.

LISP is much more than just a runtime syntax, such as its distinct evaluation model and metalinguistic core.

The JVM was chosen for Clojure because of its reach and vast ecosystem. People have ported Clojure to other runtimes, even Beam (Clojerl), where it enjoys decent success, too.

by lgrapenthin

6/3/2026 at 2:13:03 AM

All true. And I loved trying Clojure for 3-4 weeks some years ago.

Still want Erlang's runtime though i.e. the many green threads with share-nothing architecture that can communicate with each other.

by pdimitar

6/3/2026 at 5:52:38 AM

Clojure on JVM with virtual-threads (green threads) and communicating only via core.async channels (CSP inspired) using immutable data structures is pretty neat, FWIW.

by sorry_i_lisp

6/3/2026 at 2:13:41 PM

Cool. I might have to revisit, if I ever find the time. Thanks, your comment aligns with what multiple other commenters expressed.

Info gets stale. Fair.

by pdimitar

6/3/2026 at 2:31:51 AM

You don't think Erlang has an "immutability first" paradigm?

by thaumasiotes

6/3/2026 at 1:16:07 PM

Erlang is weird in this regard. It has very strong guarantees when it comes to per-process heap that make GC much simpler: no escape hatches for mutability when most immutable languages do include them! But on the other hand inter-process communication is a form of mutability (using another process as a global mutable variable is trivial) and ETS etc. present a mutable interface.

by IsTom

6/3/2026 at 1:22:58 AM

> Programming language syntax scarcely matters.

Clojure brings more than syntax though... there's an opinionated take on making all data structures immutable (as in, structural sharing [1]) by default. That's a huge difference in how you architect the program and debug it.

[1] https://softwarepatternslexicon.com/clojure/core-concepts-of...

by manoDev

6/3/2026 at 2:15:21 PM

I do love immutability. If a language does not have it I am very weary of using it. I only made exception of Rust because of how good is it for so many things + you can design with immutability first and only use mutability when you truly have no other choice and/or just want more performance and are willing to shoulder the extra effort of verification (potentially fuzzy testing even).

by pdimitar

6/3/2026 at 1:24:59 PM

> With respect, this topic in particular has been beaten to death.

Yes and no. From the discussion here I've learned about the existence of jank, which wouldn't have come up a year or so ago and might be an interesting solution to a problem for me as it evolves (that problem mainly being me not wanting to use C++ or any of the other directly supported languages in a plugin ecosystem). So these things are worth bubbling up every now and again just for the discussion to have a chance to play out.

by regularfry

6/2/2026 at 10:18:48 PM

When it comes to concurrency, what can golang's runtime do that is so special? When I tried it, it seemed like a worse version of Erlang's for people that prefer C style syntax. Depending upon your design space pervasive immutability is a huge boon too and golang doesn't have that but Clojure does - Erlang obviously having that and more.

I always wished clojerl took off.

by bcrosby95

6/2/2026 at 10:24:44 PM

I agree Golang is a worse version of OTP, no question about it, but if you are not allowed to code in Erlang/Elixir/Gleam (which sadly is 99.9% of the projects on the planet) then Golang is the next best thing.

It has footguns, sure, but with library support and discipline it can get you very far.

To me it's embarrassing that PLs still tout syntax and various other goodies, completely glossing over runtime. I might be missing something. But faux humble statements aside, I feel many others are the ones who miss something -- and that's the fact that doing stuff in parallel is a fact of life for 20+ years now and it's time all popular PL runtimes finally wake up to that fact.

If not, I am simply not considering them. And I am not saying that arrogantly though it sounds that way; there are some PLs that I _really_ liked and was almost heart-broken that I had to abandon them and not work professionally with them. But I have enough experience to know that runtime choice matters, a lot.

For the record, Racket was one of those PLs I abandoned. I know they started working on parallelism some years ago but I had to make a decision next week back then so, Elixir + Golang + Rust it is for me.

by pdimitar

6/3/2026 at 12:59:07 AM

Have you tried Lisp Flavored Erlang [0]? I never got around to trying it out. I used Elixir for a couple of years, building web backends, and I truly loved the experience. I remember wanting to try out LFE but never got around to it before moving on to a different employer/stack.

[0]: https://en.wikipedia.org/wiki/LFE_(programming_language)

by scruple

6/3/2026 at 1:04:21 AM

I have and I did kind of like it but ultimately admitted to myself that I no longer want to use too niche or too new PLs. Elixir has a fairly solid ecosystem at this point and I am only going to switch to something even bigger (I already use Goland and Rust as well).

Love the idea of LFE but it needs a bigger ecosystem.

by pdimitar

6/3/2026 at 8:57:44 AM

> the real value-add is in the runtime, not the syntax. Java has a solid runtime but it's not yet as good as Erlang's, maybe even not up to the standards of Golang

won't lie, this is hilarious. you got me from nodding along to being the spitting out food meme guy in a span of couple seconds.

JVM runtime is undeniably the most well researched and optimized runtime in history of runtimes, specifically in realm of concurrency and parallelism, it literally carries like half the world on it's back.

not to throw any shade on erlang vm - i've been a fan for well more than a decade, but other than making some interesting, but limited in practice, tradeoffs with regard to concurrency architecture, it doesn't really offer much more.

go's runtime is just a different beast altogether designed with different goals in mind and with no baggage of backward compatibility with legacy.

one particular detail i'm very grateful to Clojure for, is exactly the ability to use JVM runtime without having to touch any Java.

> Programming language syntax scarcely matters

on the contrary, it matters quite a lot.

you might be drinking some of that AI koolaid, conflating our suddenly hypertrophied abilities to produce code regardless of our familiarity with the syntax or the APIs with ability to produce and deliver good quality products, but this delusion is getting reality check as we speak.

a realization is propagating through the industry that being able to produce more code than you're able to review, comprehend and internalize is actually not a great thing.

and that's where syntax matters - it has to be high signal/noise, it has to expose you to right abstractions and it has to be pliable to allow the codebase reflect the problem in a way that minimizes cognitive load both during production and during consumption.

LLMs are language models and syntax is a crucial part of any language.

by midnight_eclair

6/3/2026 at 1:30:10 PM

LLM bashing aside (although I tend to agree), I agree with midnight_eclair. The claim that Erlang or Go are outright superior to the JVM doesn't really stand up. They're better at some things, and worse than others.

Regarding language syntax, it definitely matters. In the same way the vocabulary we use shapes our thoughts, the expression of a programming language shapes the implementation. Of course, as Clojurists know all too well, it's entirely possible to write Java in any language!

by escargot4000

6/3/2026 at 2:20:14 PM

I don't think you, I, him and others necessarily disagree at all here, it's just that living language has defects and I can't spend 30 minutes clarifying beforehand like I am doing a math proof.

To me the strengths of Erlang BEAM VM and Golang's runtime nullify their weaknesses (and of course they do have weaknesses, some are pretty hard to swallow too). To me they sit on the positive side of "right tool for the job".

I just can't work with global mutability anymore. It's an endless hopeless pit of determinism bugs. I picked my battles. Respect to whoever wants to make a career out of chasing them but that's no longer me. I want to make measurable business progress when I work and not babysit defects that should have stopped existing two decades ago.

I can agree with other posters that the JVM has come a long way. I might reassess if I get the time. And I am not bashing on anything here. I am saying what my experience showed me. To me it's tiring to pretend that all languages and runtimes are equal and I'll keep claiming they are not.

As mentioned above: I don't think we necessarily disagree at all.

by pdimitar

6/3/2026 at 11:41:05 AM

Well, you are kind of using my comment to vent your frustrations about AI while it has barely anything to do with it -- but you tried to link the two, unsuccessfully. Which is not fair as you have no clue of my stance on AI and are extrapolating a bit too much.

Syntax does not matter simply because it's an extremely leaky abstraction of the runtime below, is my point.

Of course syntax must be high signal/noise ratio, I believe every reasonable programmer will agree. But many are making entire careers in PLs where that's not the case. Hence, in practice it does not seem to matter much, for the better or the worse.

RE: runtime, try and pay attention to the parameters given in my comments. I specifically acknowledged that the JVM is a great and mature runtime but it's lagging behind on STM / actor capabilities. Tearing down a straw man is not impressive and it comes across as you trying to gain visibility by deliberately misrepresenting your discussion opponent's arguments.

by pdimitar

6/3/2026 at 1:27:31 PM

> you have no clue of my stance on AI and are extrapolating a bit too much

apologies, but maybe next time try to elaborate more on sweeping statements like "syntax doesn't matter", because in current context my assumption for why you would say that is not all that outrageous.

> Syntax does not matter simply because it's an extremely leaky abstraction of the runtime below, is my point.

that would be the reason why syntax does matter, wouldn't it? nobody wants leaky abstractions!

ironically, Clojure is a great example of a hosted language that does not leak much in terms of underlying runtime, as evidenced by the fact that it has been implemented on top of a variety of runtimes with decent control over cross-runtime code reuse.

> acknowledged that the JVM is a great and mature runtime but it's lagging behind on STM / actor capabilities

you're stating this as if it's a fact, but what is your evidence? afaik jvm has a very extensive actor model library (Akka) and clojure does include a solid STM implementation (https://clojure.org/reference/refs).

the reality is that both of these approaches to concurrency are simply not popular enough, so your grievances with JVM for (allegedly!) lacking some important features relevant to them are not in sync with the demand.

> Tearing down a straw man is not impressive and it comes across as you trying to gain visibility by deliberately misrepresenting your discussion opponent's arguments.

don't debate-bro me bro, there are no straw men and no misrepresentations of your messages. if there are invalid assumptions - it's because instead of turning this into a dozen-messages-deep interrogation of what you really meant, i'm taking shortcuts and assuming what i believe is most plausible interpretation.

by midnight_eclair

6/3/2026 at 2:28:47 PM

> that would be the reason why syntax does matter, wouldn't it? nobody wants leaky abstractions!

Well I thought we were describing our current reality, not our _desired_ one? Yes nobody wants leaky abstractions and yes they are everywhere.

Syntax matters insofar as to discourage bad habits, is what I'd refine from my previous statements. Most programmers go for the default so defaults and syntax that steers you the right way to think and write matter a lot.

That being said, people write FP Rust (myself included) and have plethora of JS libraries where immutability and FP patterns are the default. Which is a sad state of affairs but much better than nothing -- as it's introducing programmers to immutability and FP and they otherwise would never know.

> as evidenced by the fact that it has been implemented on top of a variety of runtimes with decent control over cross-runtime code reuse.

That was my top 1 reason to try it btw; I was intrigued by the fact that people are interested in making it work universally in at least two very different runtimes. To me that signals good language design and good architecture. Which I already knew; Clojure and Racket are amazing on their own.

> you're stating this as if it's a fact, but what is your evidence? afaik jvm has a very extensive actor model library (Akka) and clojure does include a solid STM implementation (https://clojure.org/reference/refs).

As already said multiple times in the thread -- my info is stale (as claimed by multiple posters).

That being said, has Akka started making full use of JVM's new green threads? Has Java itself started introducing immutability and STM / share-nothing as first-class citizens? If not, then by the "programmers reach for the defaults first" rule above I'd think Java is not yet ready. OK Clojure has these amazing libraries, kudos. Has anybody rolled up their sleeves and said "Alright, BEAM VM's reign is over, I am making the same or better runtime as them in Java / Clojure!"? If not, I'll not yet revisit.

I just don't want to deal with the endless pit of determinism bugs that global mutability nets us. The gift that keeps giving.

If Akka / Golang's runtime / Rust's various actor-emulating libraries catch up to the OTP, I'll very likely drop Erlang/Elixir because it's a struggle to have a good stable employment (or even contracting lately) with them.

Even if the BEAM VM is slower and has a few annoying sharp edges, its strengths nullify its weaknesses due to the nature of my work (HA web / API servers and also API gateways and orchestrators).

by pdimitar

6/3/2026 at 4:41:51 PM

> That being said, has Akka started making full use of JVM's new green threads? Has Java itself started introducing immutability and STM / share-nothing as first-class citizens?

Amazing how it doesn't even cross your mind that there are trade-offs to those choices. Green threads are awesome, but guess what, they come at a cost. Same for share-nothing semantics.

> Has anybody rolled up their sleeves and said "Alright, BEAM VM's reign is over, I am making the same or better runtime as them in Java / Clojure!"?

You are again presupposing the BEAM has an absolute superiority over the JVM. "Better runtime" makes no sense on its own. Better is always relative to something. Better for whom? For what?

I'd bet that you work on a traditional CRUD enterprise software, and that IO(the database) is the real bottleneck of your app. In that case, sure, the BEAM is a solid choice(so is Python, Ruby and PHP nowadays). But let's please not pretend that is all there is to software engineering.

by foxygen

6/3/2026 at 5:14:29 PM

Any good reason for your rude tone? If we are going to invoke the what crossed somebody's mind trope, I'd lead with that when talking to you -- did it cross your mind to speak calmly and not assume something "did not cross" somebody's mind?

RE: your other similarly rude comment, I have not "appealed to authority" anywhere. I said that I have used multiple PLs / runtimes and made an informed choice... for me. I don't intend to add "...for me" after each sentence. It's redundant and obviously implied when it comes to tech because obviously people have made well-working prod systems with combinations of bash and Perl ages ago. So obviously people can make nearly everything work.

If you don't intend to discuss out of position of curiosity but want to jump on people then I am not interested.

by pdimitar

6/3/2026 at 5:42:54 PM

Your first comment assumed I was "speed-running to a conclusion and squinting too hard", and this was "similar to the weird childish name-calling". I think that is in the same area(or worse) than saying "Amazing how X didn't even cross your mind". And sorry, but invoking that you have experience with X, Y, Z and thus your opinion is informed after criticizing some technology IS an appeal to authority.

> If you don't intend to discuss out of position of curiosity

I'm not the one making sweeping statements on the superiority of one piece of technology. Reading your other response, I think you are the one who have little to no curiosity in understanding how you might be wrong.

by foxygen

6/3/2026 at 5:48:19 PM

I have been on the other side as well i.e. the Java / JVM. Hence: "informed".

Your negative assumptions are tiring. Sorry that you got offended by what you quoted (and I said) but I'll drop here.

by pdimitar

6/3/2026 at 3:42:32 PM

> That being said, has Akka started making full use of JVM's new green threads? Has Java itself started introducing immutability and STM / share-nothing as first-class citizens? If not, then by the "programmers reach for the defaults first" rule above I'd think Java is not yet ready.

> OK Clojure has these amazing libraries, kudos. Has anybody rolled up their sleeves and said "Alright, BEAM VM's reign is over, I am making the same or better runtime as them in Java / Clojure!"?

will akka use green threads? i'm sure it will when the developers behind it deem them useful.

will jvm add immutability, stm and share-nothing primitives that (i assume you allege) are missing? sure, i guess, when it becomes frequent enough ask.

you make it seem as if the world of software development is in some constant battle for supremacy, but it just isn't.

there is no "BEAM VM's reign". and if there was - it's unlikely that anybody would care to topple it. people just want to get their job done and they use whatever tools are available, familiar and convenient for them.

> I just don't want to deal with the endless pit of determinism bugs that global mutability nets us

and a lot of people agree with you. and there's a lot of tools that address that. and i can assure you, when working with clojure, even on the blasphemous mutable jvm runtime, that class of bugs is non-existent.

by midnight_eclair

6/3/2026 at 5:40:23 PM

Well, I don't think you and I disagree on the premises, with the exception of you believing that I make some outrageous general claims -- which I did not.

> you make it seem as if the world of software development is in some constant battle for supremacy

I could have misinterpreted other people in the past -- very possible. But I also stopped caring about "battles for supremacy" a long time ago and at this point in life and career I simply use my experience and brain to go where my work is more productive, deterministic and fulfilling. To me immutability, share-nothing actors, strong vertical scalability (where a lot of PLs and runtimes do well, not only my favorites) and DX (like live prod REPLs and generally trivial observability) are those axii along which I thrive.

You and a few others seem to have emotional reactions to this which, I assure you, are very unnecessary. I ain't threatening neither your livelihood nor preferences.

by pdimitar

6/3/2026 at 1:56:01 PM

The JVM is perfectly capable of Golang-style green threads now. As for Erlang, the creator of Clojure have commented in the past on why he dislikes the Actor model, and I think it is a fair criticism. Sometimes I see people praising Erlang VM as some panacea in which all the VMs should strive to be like. This is overly simplistic in my opinion, and ignores the huge trade-offs that the Erlang VM has.

by foxygen

6/3/2026 at 2:09:31 PM

You might be speed-running to a conclusion and squinting too hard if you use the word "panacea". Similar to the weird childish name-calling people do in Rust threads (somebody met one brainless zealot and now of course they'll judge a community of hundreds of thousands of devs by that one loony).

I used Java, Golang, Rust, Elixir (so Erlang).

My opinion is informed. STM / share-nothing-actors lend themselves amazingly well to online services for many reasons, better explained by other people and documented elsewhere (and I did not come here to advocate but to express preference and offer the take of somebody who has been around).

I am not denying that the JVM might have almost caught up in the meantime. More than a decade ago it did not.

And yes the BEAM VM is absolutely and markedly _not_ a panacea. It has a few weird sharp edges. It's just that in my work I have found having to avoid them still worth it compared to the alternatives (global mutability and more primitive parallelism which was the case for the JVM for decades).

by pdimitar

6/3/2026 at 4:16:00 PM

I have used Clojure(JVM), Elixir(so Erlang) and a bit of Golang professionally too. So my opinion "is informed" too for that matter, but this kind of appeal to authority adds nothing to the discussion.

> I am not denying that the JVM might have almost caught up in the meantime. More than a decade ago it did not.

This presupposes that the JVM had something to catch up in the meantime. Again, this lacks nuance and brings nothing to the table. The JVM makes different trade-offs than the Erlang/Golang VM does, and has different strengths and weaknesses. Both of your comments completely ignores that.

> It's just that in my work I have found having to avoid them still worth it compared to the alternatives (global mutability and more primitive parallelism which was the case for the JVM for decades).

Clojure runs on the JVM and avoids mutability pretty well. It is amazing for writing concurrent software, and has been for many years(i.e more than a decade ago).

> Similar to the weird childish name-calling people do in Rust threads

I've seen people do similar things to the JVM.

by foxygen

6/2/2026 at 10:38:11 PM

Are JVM virtual threads not on par with golangs's concurrency? I think core.async even uses virtual threads now

by chamomeal

6/2/2026 at 10:40:00 PM

If they are, I have not heard about it (which does not mean much, I check Java once a year). And if they really are then I'd give Java a serious look again because it's a mature ecosystem that was gimped by ancient runtime decisions for literal decades.

by pdimitar

6/2/2026 at 11:37:31 PM

As of Java 24 (Java 25 being an LTS) I'd say they are equivalent. You can use a virtual thread just like you use a regular thread and there's basically no handicaps or gotchas. In Java 21, when they were released, there is a gotcha that the pretty normal use of the `synchronized` keyword would pin a "carrier thread" which ends up blocking all virtual threads from running on that carrier thread.

Pinning can still happen in some much more rare cases, same with go. For example, FFI.

The memory usage, performance, etc are all go like. You can spawn millions of virtual threads with hardly and memory requirements and without overburdening the OS with context switches. The JVM also enjoys faster GC performance with virtual threads.

by cogman10

6/3/2026 at 1:11:36 AM

^^^ This.

by raspasov

6/3/2026 at 3:51:01 AM

Your knowledge is outdated. Go check again.

by vips7L

6/3/2026 at 9:59:22 AM

I think you might reevaluate the runtime claim, since the JVM is perfectly capable of stackful coroutines these says.

by DarkNova6

6/3/2026 at 1:10:27 AM

What can the Erlang / Golang runtimes do that the JVM can’t?

by raspasov

6/3/2026 at 1:13:27 AM

Thousands of share-nothing actors (fibers / green-threads) with first-class support for communication between them, for a start. Erlang/Elixir -- immutability as well.

by pdimitar

6/3/2026 at 2:14:02 AM

"As a rule of thumb, if your application never has 10,000 virtual threads or more, it is unlikely to benefit from virtual threads."

https://docs.oracle.com/en/java/javase/21/core/virtual-threa...

by lgrapenthin

6/3/2026 at 3:24:11 AM

BEAM threads are kinda magicsauce tho, instructions have a cost and after a certain cost total (quantums) the scheduler can divert to another virt thread to guarantee forward progress. Also the immutability rules etc make it easier to optimize this switching.

by whaleofatw2022

6/3/2026 at 5:26:06 PM

Eh, reduction counting isn't magic. Golang manages similar preemption semantics without counting that many operations (some tight loops do have barriers inserted every so often, but that's the exception and not the rule). And reduction counting has some serious costs! It slows the runtime down a shitload (and the BEAM is already in the bottom half of interpreted language runtimes by speed) and makes lots of JIT-flavored runtime optimizations slower or harder to implement.

I like immutability too; I wish Java and Golang did more of it. It costs a lot in terms of unexpected copies in the BEAM though, there's less copy-elision optimization than you'd think. That especially bites if you're doing a ton of message passing, because of how process heaps are implemented and how garbage collection (traditional or ETS/ThreadProgress-based) works.

I think what I want is something like Golang but with goroutine-based ownership semantics (or Rust with the Go runtime and goroutines): en excellent scheduler for extremely light-weight green threads, no refcounting or reduction counting, and all the clever optimizations around channel sending and copy elision--but no ability to use a value after it's sent to a channel, and only channel-based access to shared global state. That'd get most of the benefits of process-local heaps but without the (copying, cache/memory fragmentation) drawbacks.

by zbentley

6/3/2026 at 2:16:07 AM

Obviously. But it's really nice to have the option, and none of us knows the future. I've been bitten by those "0.1% chance" things much more times than I would be not-embarrassed to admit, and I know I a not alone.

by pdimitar

6/3/2026 at 2:25:42 PM

I believe the point they were making is you can have millions of virtual threads on the JVM no problem. Your information on the JVM is outdated.

by andersmurphy

6/3/2026 at 2:29:28 PM

Good, thanks for the grounding. I'll have to reevaluate at one point then.

As I just posted in another comment (https://news.ycombinator.com/item?id=48384622), I'd probably drop Erlang/Elixir due to difficulties of employment and contracting -- if the more popular languages get those STM / share-nothing runtimes.

by pdimitar

6/3/2026 at 3:50:12 AM

Virtual threads can do that too.

by vips7L

6/3/2026 at 2:19:48 AM

What kind of software actually requires this? Honest question. Anything I can think of would probably be written by C++ devs

by rashkov

6/3/2026 at 4:45:01 AM

"requires" is of course subjective, there are always multiple ways to do something. But sometimes it is convenient to model a system as concurrent execution streams, for example: multiple sessions (servers), multiple entities (games, robotics), multiple in-flight transactions (any kind of i/o or concurrent compute). Agreed these are often C++ use-cases but there are obvious benefits to using Erlang or other virtual machines: memory safety, isolation, fault tolerance.

by RossBencina

6/3/2026 at 2:22:54 AM

Web / API services during bursts. Or just when you _really_ don't want to scale horizontally.

Elixir / Golang can do this very well. And they do. I have supervised, led and authored such projects that are in production to this day.

Rust too but it's lower-level and you kind of have to hand-roll OTP which of course will always fail.

by pdimitar

6/3/2026 at 8:29:01 AM

from experience, during bursts it's never actual web/api server that is bogged down, it's the downstream io bottlenecks.

if your accepting layer is abstracted away and implemented correctly, there is very little performance difference between different concurrency approaches and all you're exposed to as developer is implementation of your handler functions.

by midnight_eclair

6/3/2026 at 5:53:44 PM

Not the case; good abstractions are valuable, but the performance differences between runtimes are very real.

Take the example of some simple HTTP<->blob store service gets slammed with millions of requests when someone using the API does a backfill via some framework on their end that aggressively scales request volume up and out.

Something like, say, async Python/starlette with coroutine-per-thread is gonna perform worse than Erlang, which in turn is gonna perform worse than Go.

You're right that those differences are sometimes marginal when the latency of whatever IO the backend's doing dominates the equation. However, in my experience huge volume surges show issues with the runtime (the thing managing/launching multiplexed request handler routines) or the ecosystem (the backend IO libraries' ability to work with the runtime's IO multiplexing and make things like request coalescing easy or automatic) more often than you'd think.

It really takes surprisingly little volume to cripple a return-hello-world Phoenix app that indirects the "hello world" behind way too much middleware and message passing; it takes even less to kick over, say, a Gunicorn instance returning "hello world" at the bottom of the Django middleware stack. Golang with Gin, on the other hand, is surprisingly hard to cripple in the same way. And I say that as someone who likes Elixir and Python a lot more than I like Go!

by zbentley

6/3/2026 at 2:37:14 PM

(Upvoted for a really relevant and valuable refinement to the thread.)

Admittedly that layer is almost always abstracted i.e. AWS / GCP and various other smaller hosted solutions that handle a good chunk of load balancing for us. In that landscape BEAM VM's strengths shine even brighter. I've seen firsthand that you can in fact bring a BEAM VM to its knees if you expose it just like that to the net. It's not pretty. Golang fares a touch better and Rust seems almost immune (provided one does not screw up their caching layer and don't do elementary N+1 query mistakes).

by pdimitar

6/3/2026 at 3:03:31 AM

>share-nothing actors

although this is a deliberate choice rather than some accidental defect. Clojure went with STM as its concurrency model, if you're not buying into that and you want an Actor-centric language it's not the right choice to begin with.

by Barrin92

6/3/2026 at 9:09:08 AM

STM is seldom used in modern Clojure projects, it is certainly not the dominant model. Most projects I am aware of use a few or even exactly one atoms with immutable data structures.

by funcDropShadow

6/3/2026 at 1:14:11 AM

Low memory usage.

by Thaxll

6/2/2026 at 11:44:21 PM

> Programming language syntax scarcely matters. It does to some extent but we the programmers tend to over-romanticize it. The runtime and its properties are the much better thing to optimize for.

I'm not sure I understand this argument. Java and Clojure share a runtime, but an idiomatic Java codebase is going to have a very different architecture and design to an idiomatic Clojure codebase. Conversely, a codebase written in Go may end up looking very similar to a codebase written in Java, despite using different runtimes.

by weavejester

6/2/2026 at 11:46:45 PM

I mean runtime guarantees and features. In this case: effortless / near-invisible concurrency and parallelism.

As mentioned, I did like Clojure. I'd switch to it if it was running inside the Erlang runtime (like Elixir does).

by pdimitar

6/3/2026 at 12:08:29 AM

To be clear, I'm not questioning your choice of runtime or language. I'm just curious why you think that "Programming language syntax scarcely matters", as to me that seems the same as saying "How a codebase is architectured and designed scarcely matters".

by weavejester

6/3/2026 at 12:12:49 AM

I don't see how the latter follows from the former? The former is much bigger and more abstract; syntax is just one of the vehicles to try and codify it.

F.ex. if you have an universal construct of green threads / fibers then 7 PLs could express it 7 different ways, yet underneath they'd all be the same.

by pdimitar

6/3/2026 at 12:22:48 AM

The programming language informs the design of the system. As I said in my earlier comment, an idiomatic Java codebase is going to be designed very differently to an idiomatic Clojure codebase, even if they both intend to solve the same problem.

by weavejester

6/3/2026 at 1:05:02 AM

But that's still not a function of the syntax per se; Java has no immutability encoded in its runtime, hence it does not offer it as a syntax either.

by pdimitar

6/3/2026 at 1:29:47 AM

Scala has no immutability encoded in its runtime either (as it's the same as Java), but yet syntactically it's immutable in practice. Will the JRE technically allow a val to be edited through some third party thread inspecting your code and messing with memory? Sure. But it's not a reasonable fear in any real world environment, where I cannot remember, in 15+ years of professional scala, a case where anything I expected to be immutable (everything) to be mutated under me. Nowadays people using in in an FP style don't even think of the physical threads, as green thread libraries are taking care of all the scheduling.

So focusing on the runtime's guarantees doesn't seem like a practicality focused argument to me.

by hibikir

6/3/2026 at 1:45:33 AM

You are citing a commendable exception (Scala) to tear down a bigger argument which is not exactly a fair discussion.

Furthermore, if you trace my comments, you'll see that I had to choose PLs years ago (12+ to be precise). Things were quite different at the time. Java might have almost caught up today; back then we couldn't even be certain `synchronized` is stable all the time. Just saying.

Scala did very well then, judging by your words. I could probably offer a loose analogy to Typescript as well; while it does compile to JS underneath, they added a stricter layer that makes programming in it more deterministic and stable. (Not the same thing because my main point was "runtime" but hey, show me a perfect analogy.)

You are free to say your last sentence. I am free to disagree. My practice has shown me that runtimes bleed into syntax almost always. Exceptions exist, sure.

by pdimitar

6/3/2026 at 1:58:20 AM

But syntax must necessarily include what it's representing, no? For instance, `{:a 1}` represents an immutable map in Clojure, in the same way that `42` represents an immutable integer in Java.

by weavejester

6/3/2026 at 2:05:56 AM

Agreed, though I didn't mean "constants" when I said "immutability".

by pdimitar

6/3/2026 at 1:23:23 AM

Those differences are not due to the syntax, they're due to much deeper things like the differing type system.

by Boxxed

6/3/2026 at 2:13:21 AM

I'm not sure I agree. Certainly there are differences other than syntax, but that doesn't mean syntax is irrelevant. For instance, would Clojure programmers use maps as much if there was no syntax for map literals?

Syntax determines what parts of a language are within easy reach, and therefore affects how programmers use the language. Tools that a syntax make easy are used often; tools that syntax makes hard are used infrequently. This indirectly impacts how a piece of software is designed.

by weavejester

6/3/2026 at 3:21:48 AM

This is very much what I meant in the post (hi, I'm the author :P)! CL has maps, but they're a pain to use - not just because of the syntax, but because of the relative dearth of standard library functions to work with them compared to say, lists or even vectors.

by acdw

6/3/2026 at 2:39:48 AM

Good thing you have a variety of those nowadays. Clojure runs in the browser, Node.js, cross-compiles to Dart, works stand-alone via babashka and has a brand new C++ interfacing implementation in Jank.

The ergonomics of using a proper REPL and interactive programming is hard to beat.

by beders

6/2/2026 at 10:19:47 PM

Yeah, the content + feel felt like I'm reading this in 2013.

Nothing wrong with that, it's a good thing that stuff is discovered anew [as opposed to being lost/forgotten], but it did bring a smile to me.

by agambrahma

6/3/2026 at 2:14:33 AM

Yeah, the content + feel felt like I'm reading this in 2013.

by dundunUp

6/3/2026 at 12:59:16 PM

Not even to optimize for, but to write correct programs you really need to understand the runtime which is usually broader than the syntax.

All Clojure (lisps) do is remove the stupidity of syntax.

Even if syntax is the minor thing, why wear a stupid, uncomfortable shirt while running when you could wear one so comfortable you scarcely feel it?

by wellpast

6/3/2026 at 2:42:50 PM

Well I agree, that's why I use Elixir and not its underlying Erlang.

And I agree that most LISPs remove the stupidity of syntax. Very true.

by pdimitar

6/3/2026 at 12:51:58 AM

> Programming language syntax scarcely matters. It does to some extent but we the programmers tend to over-romanticize it. The runtime and its properties are the much better thing to optimize for.

But that really depends on what you're doing. For example if I'm not mistaken Amazon was run for a very long time on a Java backend. And so was GMail's backend (and back then GMail's frontend was, IIRC, Java converted to JavaScript using GWT).

And by "early Amazon" and "early GMail", we're already talking about massive scale. It's not as if the JVM got worse since then (as someone commented: a recent addition is that Clojure now use Java's virtual threads) and it's not as if it didn't scale.

So I'd say having Clojure on top of Java (for those using that Clojure: there's also ClojureScript, babashka, etc.) ain't really a problem, as long as you're fine with the occasional Java stacktrace and Java ecosystem (GP mentions that btw: that he's not familiar with Java and that, I think, can be a bit of an issue).

I'm not sure Clojure is about it's syntax: I like the focus on immutability / pure functions and I do really dig the REPL a huge lot. In addition to that something has to be said as to the incredible stability of the language and many of its libraries.

The big value add to me is that I can have a REPL and inspect, in dev (or in prod but that'd be wild), the app I'm working on. And manipulate it: redefining variables and functions etc. And it's not some hacky hot-reloading bolted on as an afterthought kludge: it's a real Lisp REPL. There's value in that IMO.

by TacticalCoder

6/3/2026 at 1:09:41 AM

Elixir has all that _and_ Erlang OTP's amazing guarantees. Hence I landed on it.

Elixir also offers LiveBooks i.e. you can create pre-made recipes with which you directly remote into your staging / prod and do stuff.

All that with immutability and potentially 6 digits of actors / green threads with a share-nothing architecture.

---

RE: early Amazon / Google, sure. They made do with what they had and it was and still is a heroic effort. But can we agree that they succeeded _despite_ the numerous warts and defects of the PLs and their runtimes at the time? Not _because_ of them?

I feel that people latch onto the misleading "they succeeded with language X and are big, hence the language X is great" thing way too often. No. It's not true. The only thing that follows from "big company A made it big with language X" is: "company A has an amazing engineering team". Nothing else.

by pdimitar

6/3/2026 at 2:09:43 AM

> Programming language syntax scarcely matters.

Certainly it matters much less in the modern era.

However, certain fundamental decisions of a language can be dealbreakers.

Requiring declarations on your functions and giving those declarations sigils so that they can be parsed quickly is an important syntax decision. Almost every modern programming language has converged to this idea.

Or take, for example, Lua. For me, personally, the 1-based-ness of Lua is simply a dealbreaker no matter how good anything else about it is.

For the "Lisps", I LOATHE the fact that you traverse lists and vectors in completely different ways--you can't just drop any container-ish thing into something that iterates/collects it. This is something that both Clojure and Racket seem to agree on--you have something that acts like a "collection" and you can walk across it the same way regardless of the specific type of collection it is. Of course, that is why a bunch of Lisp purists loathe Clojure and Racket while I like those languages. Shrug.

I find RAII (Resource acquisition is initialization) to be the source of all things evil if it infests a programming language. The popularity of C++ and Rust speaks to the quite large number of people who think my opinion is bullshit.

So, yeah, base syntax matters far less than it used to. But the engineering decisions that went into making that syntax correspondingly are far more important.

by bsder

6/3/2026 at 8:52:27 AM

I agree with most of what you said, but I am puzzled about your claim about RAII.

Whether it is good for any kind of resource acquisition to look the same like an initialization is debatable.

On the other hand, I cannot see any counterargument to the principle that releasing any resources should not be done explicitly, but only implicitly, upon leaving a block (using reference counts for shared resources).

I doubt that you advocate for the use of explicit release commands for resources, which are a notorious source of bugs, so what is that you consider as not being the same as RAII?

RAII was a not very useful acronym that was just another form to say that the C or C++ programmers should never use the PL/I style of explicit free commands, despite the availability of functions like "free()" or "close()" in the standard library, but both memory and files and any other kinds of resources should be managed with automatic releasing.

I do not see how this sound principle can infest any language.

Obviously, I have seen examples of bad RAII implementations, like I have seen examples of misuse for any other programming principle.

by adrian_b

6/3/2026 at 11:04:17 AM

> I doubt that you advocate for the use of explicit release commands for resources, which are a notorious source of bugs, so what is that you consider as not being the same as RAII?

Those are not the only choices.

Garbage collection is at one end of the spectrum--fully manually managed is at the other end of the spectrum. There is also another axis of acquiring/releasing allocation by object or acquiring/releasing object by pool. And, if you have it, there is the axis of allocate only at startup and never free until end of thread/application vs. allocate only at a frame of of time and then destroy them all at the next frame vs. allocate whenever and wherever.

RAII encourages the usage of lots of tiny individual objects allocated whenever and wherever all with their own lifetime cycles and makes understanding the memory usage of your application very difficult (this was the whole reason Rust was made--C and C++ made managing memory in Firefox ridiculously diffused and impossible to corral).

And, I'll be blunt, I think that Rust/Zig/C3 etc. are not the right direction in spite of the fact that I use Zig a lot. I think that the garbage collected languages cede far too much in terms of performance to the compiled ones and GC languages (like say OCaml) should be being used for systems programming more often.

For example, I think we would all be in much better shape against AI vulnerability scanners if more systems programs were in GC-type languages.

by bsder

6/3/2026 at 2:20:50 AM

I think we can easily agree they are two entities (syntax / runtime) that feed off of each other. And I do agree that previously the syntax mattered more.

(I very much agree on Lua btw.)

Personally I am very disheartened. Surely algebraic data types should be universally a good thing and all PLs should gradually adopt them? But no, endless HN / Reddit threads bike-shedding.

Oh well.

by pdimitar

6/3/2026 at 3:23:38 AM

Too Many Requests

The page you have tried to access is not available because the owner of the file you are trying to access has exceeded our short term bandwidth limits. Please try again shortly. Details:

Actioning this file would cause "www.acdw.net//clojure/" to exceed the per-day file actions limit of 80000 actions, try again later

by tartoran

6/3/2026 at 11:46:06 AM

I spent a week with Clojure and coming from other functional languages my problem was not Clojure, it was dynamic typing. I got strange bugs in the standard library because I accidentally sent in nested incompatible instances of objects and it was really hard to figure out what was wrong in a quick way. With typesafe languages you are stopped at compile time.

by perarneng

6/3/2026 at 12:55:20 PM

Clojure was explicitly designed to be dynamic. It’s a feature, not a bug.

https://clojure.org/about/dynamic

Until you get better at not making mistakes that the training wheels of a static type system “protect” you from, lean into the REPL as a means to build up small correct expressions into larger ones.

by wellpast

6/3/2026 at 1:59:08 PM

It’s both.

by moi2388

6/3/2026 at 2:59:40 PM

"Until you get better" is such an arrogant take.

It's not just about skill. It's about maintainability, ease of refactor, and modeling invariants in your code in a way that they can be checked by the machine (the compiler) without every single developer having to maintain them in their head.

Clojure even knows this is an issue and many people use `spec` to sort of retrofit static typing.

Dynamic typing was, is and always will be a mistake. There is nothing you can do with dynamic typing that you cannot do with a sufficiently powerful static type system - and it doesn't have to be something absurd like Haskell's. You basically just need structural typing and type inference and some type-level programming constructs.

The worst part about Clojure is the community. Rich Hickey has cult-like status and the only thing clojurians can do is parrot his inane commentary.

by IceDane

6/3/2026 at 4:17:02 PM

I too agree that "until you get better" isn't a good take. To err is human, and even the most experienced developers make mistakes.

That said, you don't get static typing for free. As with many things it's a trade-off: you catch some errors at compile time in exchange for working within the confines of the type system. The ultimate hope is that the time you spend fiddling with types is going to be less than the time you spend debugging type errors.

> There is nothing you can do with dynamic typing that you cannot do with a sufficiently powerful static type system - and it doesn't have to be something absurd like Haskell's. You basically just need structural typing and type inference and some type-level programming constructs.

Haskell doesn't have a complex type system for no reason; it's necessary to encompass everything it wishes to do, and even then it's not as flexible as a dynamically typed language.

For instance, how would you statically type Clojure's `assoc` function? It's not at all trivial if you want to retain the type information of the keys and values.

by weavejester

6/3/2026 at 6:42:15 AM

> Clojure makes a big point of being a hosted language, that is, a language that runs on a premade runtime.

This is why I am found of the community, the symbiotic approach of two language communities working together.

by pjmlp

6/2/2026 at 10:05:29 PM

> I do wish there were an easier way to move in the ]}]})))}-ness of block ends though.

I’m not quite sure what this means. How is it different/worse than all parens..?

fyi I use paredit and just hit ) and it moves me past any kind of paren/bracket. But even without that you can just hit left and right..?

by meken

6/3/2026 at 3:32:49 AM

They are a pain if they get unbalanced if you aren’t using paredit. Like if I vi delete the last line of a function out of habit it’s a pain to get them back in the right order.

It’s easier if everything is parens, just hit paren til the errors are gone.

by everforward

6/3/2026 at 5:47:02 AM

Ah I see. That makes sense.

That’s making me really thankful to be a paredit user.

by meken

6/3/2026 at 4:07:02 PM

Learning paredit is on my list of things to do.

I've been loving Clojure for hobby projects lately but my editing setup sucks for Clojure. The vi commands I'm used to using are bad in Clojure (eg copying by line almost always means unbalanced parens), and the autocomplete LLMs are very inconsistent about closing syntax correctly.

It seems super cool, I just haven't done it enough for my brain to reach for paredit keybinds instead of vim chords.

by everforward

6/3/2026 at 3:25:04 AM

I use Emacs's built-in structural editing bindings, which doesn't have the auto-move-past any kind of paren/bracket thing. Maybe I could add that in.

But I was talking about like, when refactoring, I'll maybe change something from a list to a vector, and I have to change the delimiters at front and back. Or, where electric-pair does do the move-past-all-parens thing when I just spam ), it doesn't do that with ]}]}]]}}]})).

by acdw

6/3/2026 at 9:45:13 AM

I don't recall the exact name, but I believe it's forward-up-sexp which allows you to jump forward past the next closing delimiter. Though if I'm not mistaken only the backwards one has a default binding.

by tmtvl

6/3/2026 at 5:47:52 AM

I see.

Have you ever tried paredit? It’s pretty much a lifesaver for this kind of thing.

by meken

6/3/2026 at 1:28:27 AM

Exactly. Paredit for the win.

by drob518

6/2/2026 at 10:02:38 PM

The functional paradigm is a bit uncomfortable at first, but it does make problem solving feel... different. I personally find OOP to be the most intuitive for large scale systems design, but that's just me.

Most models do not perform particularly well in Clojure, but OpenAI models fully utilize the power of the language. Subjectively, it kind of seems to match the personality. Data at https://gertlabs.com/rankings?provider=openai

by gertlabs

6/2/2026 at 10:49:54 PM

> I personally find OOP to be the most intuitive for large scale systems design, but that's just me.

The beauty of Clojure shines through when you want to change something that cuts through a large part of a large project. If you are using mutable data, you may end up with many bugs from various pieces of code mutating objects inconsistently. With Clojure, if someone hands you data, you can't possibly break some distant piece of code by updating an object: it's just not possible because you only ever make fast, updated copies. The more complicated your codrbase gets, the more this benefit is realized.

I actually kind of think of it as an easier mechanism with similar outcomes to Rust's borrow checker. Only one piece of code ever owns the data so things end up much safer. However it is way easier to use IMHO because you just know that zero people own anything and everyone can read everything.

It also makes converting some code to be multi-threaded extremely easily and with some constraints guaranteeably correct.

Lots of dovetailing features neatly put together for both clarity and less bugs and more usable cores which are probably sitting idle.

by gleenn

6/2/2026 at 11:32:01 PM

> I personally find OOP to be the most intuitive for large scale systems design, but that's just me.

Once you're more comfortable with it and want to try a typed functional programming language, I highly recommend checking OCaml (or SML, if you're into old school tech) and see how the Module Functors are applied, most software will look extremely over-engineered after you write a few functors. It's the feature I miss the most when coding in F# or Gleam, for instance.

by schonfinkel

6/2/2026 at 10:31:47 PM

Raw models aren't as effective with clojure as they are with typescript or python, but clojure has a superpower that most other languages don't have: the REPL! Specifically nREPL and the ecosystem around it.

An LLM is only as good as its feedback loop. If your LLM can actually test the code it writes, it's going to be much more effective. Static types are a form of feedback (if it can use the LSP), unit/integration tests are another.

Clojure has an exceptionally good repl. LLMs can eval any piece of any function. They can test out functions they aren't familiar with. They can fetch data, try out different arguments, try different approaches before committing to one. They can query a database (read-only connection, of course), look at the result, fetch data from an API, and stitch it all together. It can even hook into your running program and debug it from the inside out!!

It makes it so much more effective at using libraries or paradigms that it isn't trained on. In my experience, hooking an LLM up to the clojure repl lets it write WAY more complex stuff. I'm talking like 10x more complex programs with zero errors, cause it can literally try it out every little piece before putting it together. It's like watching a human programming. But like, really fast.

Sorry I get a little ranty when clojure + LLMs come up, because I don't think most people realize what they're missing out on. It's crazy stuff. It's also easy peasy if you use vscode. There's an extension called calva-backseat-driver that just hooks it all up for you. Gives copilot access to the repl, and I think it exposes an mcp if you want to give claude access too.

by chamomeal

6/2/2026 at 10:38:37 PM

GPT 5.4+ models are extremely good at writing Clojure, agreed. In the agentic coding part of our benchmark, they do have access to the REPL via bash if they choose to use it. Filtered here: https://gertlabs.com/rankings?mode=agentic_coding

by gertlabs

6/2/2026 at 10:18:21 PM

Thanks for the link!

What would you say is missing from Clojure for large-scale OOP design? As I understand, Clojure gives you OOP a la carte. Objects (via maps/records/structs), polymorphic dispatch (via multimethods/protocols/case), types (via Malli/TypedClojure), inheritance (via derived, isa?, etc), some encapsulation (via defn-/^:private)...

by xoxolian

6/2/2026 at 10:35:24 PM

Not the person you're replying to, but have you tried TypedClojure? I've always thought clojure-with-types would literally be the perfect language, but I also read TypedClojure is more of a research project than a real language that you should use in prod.

by chamomeal

6/2/2026 at 11:30:31 PM

No sorry, of the things I've listed, I'd never seen nor heard of a project that uses Typed Clojure, nor probably inheritance via dervied/isa?.

For static (partial) typing, I instead use Malli schemas. I do this for every larger Clojure program I make, because there's always something that needs paranoia, or it's handy to generate example data.

by xoxolian

6/2/2026 at 10:34:58 PM

I might just be a simpleton -- I never had the resolve to try an ambitious project in Clojure. I was not aware that you could get full OOP though, what you are describing feels like yes technically possible but kind of a hack to get inheritance / no type hierarchy enforcement. I'm no expert on the language though

by gertlabs

6/2/2026 at 10:52:17 PM

I actually disagree. Once you remove the cruft and crap of the involved syntax, good OOP design tends to look damn close to FP design. So I flip your point of view - class based OOP is the hack - despite not really using Clojure or FP in my dayjob or hobby projects anymore. Most fun I had with OOP was definitely Common Lisp though.

by bcrosby95

6/3/2026 at 5:38:14 AM

It's fascinating that Clojure has consistently the best performing solutions and yet at the same time such a low success rate.

Do you have an idea as to why that is?

If I had to guess, two things lowering reliability:

A) Balancing parens might be tough on an LLM one-shot.

B) LLMs generate tokens sequentially, but s-expressions mean the first forms to be evaluated in a body are usually the last to be written, so the LLM has to sequentially generate layers of evaluation backwards.

by Hammershaft

6/3/2026 at 7:19:00 AM

First, we would need to agree on what "such a low success rate" means. Programmers have a thundering herd mentality: there are usually 2-3 "top things" that are in fashion at any given time and the herd tends to go towards these top things. They are not necessarily good or "successful" (however you define that term), they are just popular today.

From my point of view, Clojure is a very successful language. It has been in stable development for >10 years now, with no major breaking changes (!). I was able to start a business using it and now make a living from it, all of it possible largely because Clojure reduces incidental complexity so much.

Now, as to LLMs, I can see this discussion is mostly theoretical, so let me pitch in with data. I've been using LLMs for Clojure for a while now and it works fantastically, from what I read about other languages, quite a bit better for me than for others. Balancing parens was a problem for early LLMs without tools, Claude Opus with clojure-mcp tools doesn't encounter that problem at all.

Additionally, the ability to try things in the REPL means that LLMs are very effective: all hypotheses and solutions are immediately tested, with automatic feedback.

Overall I get great value from LLMs and I am able to solve large problems with them.

by jwr

6/3/2026 at 1:28:45 PM

I've found it helps to give the model a lower nesting limit than you might give a human who has access to a paren-balancing editor. If all functions are shallow, there's less opportunity for paren balancing to get out of control, and reasoning about the evaluation flow doesn't have to jump back and forth so much.

This also doesn't hurt the code from a human reader's point of view.

by regularfry

6/3/2026 at 6:50:34 AM

If B), then maybe the LLM should be instructed to prefer things like the -> and ->> operators. So the first forms evaluated are also the first written.

by xoxolian

6/2/2026 at 10:16:27 PM

Not sure if I'm reading this right, but the "success rate" table for OpenAI models shows Clojure near the bottom. And if I switch provider to Anthropic, success rate for most languages, including Clojure, goes up dramatically.

by andai

6/2/2026 at 10:28:35 PM

Success rate includes syntax/compilation failures as well as environment rule violations, and is almost entirely from one-shot code generations. Percentile shows how well the working submissions perform.

In long horizon agentic coding evaluations, strong models fix the syntax and percentile and it becomes a direct comparison of which submissions per language performed the best on average. You can filter for that here: https://gertlabs.com/rankings?provider=openai&mode=agentic_c...

by gertlabs

6/3/2026 at 1:31:45 AM

> I personally find OOP to be the most intuitive for large scale systems design, but that's just me.

At one point, I was the same. But after going functional in Clojure, I can’t imagine going back. Using maps nd just having common functions that transform data into different data is definitely the way to go. This is with your time: https://youtu.be/aSEQfqNYNAc

by drob518

6/3/2026 at 1:46:37 AM

Functional is far more comfortable to me. Trying to model all that state spread through out your program with no way to really isolate it or just reason about a small part of the program at a time, I find very stressful.

by jimbokun

6/2/2026 at 11:02:22 PM

Rich Hickey's: Are We There Yet may be interesting to any one here: https://www.youtube.com/watch?v=ScEPu1cs4l0

I found this to be one of the more interesting talks I've watched.

Like you (I think) - I love functional languages.

But there's a problem I can't really figure out how to articulate where they reach a level where they stop "just working" imo. Maybe it's just me being too dumb.

by onlyrealcuzzo

6/2/2026 at 10:24:38 PM

I wonder if the author is familiar with Smalltalk - it has a very small syntax. In some ways so does Lisp, in other ways it has more than every other language, depending on what you think about operators versus functions.

by NetMageSCW

6/3/2026 at 3:25:53 AM

I have heard of Smalltalk and it is intriguing but honestly I don't even know how to get started with it lol

by acdw

6/2/2026 at 10:50:54 PM

"Lua: everything is a table

Tcl: everything is a string

Lisp: everything is a list"

Python: {"everything":"dictionary"}

by smitty1e

6/3/2026 at 2:07:37 PM

s/everything is/everything seems to me/

by karolinepauls

6/3/2026 at 6:03:15 AM

I am able to see the link just fine.

by roshanroyj

6/3/2026 at 1:14:23 AM

Thats nice but not many jobs for it

by zuzululu

6/3/2026 at 1:44:34 AM

If that’s your concern you don’t need to be concerned with any technical quality of any language. Just count job postings by language and learn the one with the highest value.

by jimbokun

6/3/2026 at 1:49:25 AM

if there isn't any jobs for it it probably doesn't have the appeal or communicate economic value

by zuzululu

6/3/2026 at 1:38:06 PM

The question is appeal to whom. Large employers want you to learn popular languages so that you're a commodity in a liquid market. But that's not a signal of economic value; it's the reverse. It's saying "I'm entirely replaceable."

What you can predict is that those employers for whom clojure (or any other minority language) is either acceptable or preferred are deciding that they don't want commodity, low-margin employees. It's a signal that they prefer not to buy the mass-market offering, and ought to expect to pay a premium.

What that means is that if your only way of finding jobs is to be one of the mass-market crowd, you're unlikely to find a premium-paying employer because that's not where they're looking.

by regularfry

6/3/2026 at 4:36:44 PM

its not large employers only. you need a steady stream and large enough pool of candidates for any size of a business.

if you limit yourself to a tiny almost invisible slice you are betting your business on finding candidates and relying on that small pool of talent. employees come and go and you would have to deal with this issue constantly.

by zuzululu

6/3/2026 at 5:37:25 PM

Yes not only large employers, but it's easiest to think in those terms.

And it's only true that "employees come and go" is a problem if 1. you assume turnover has to be high, and 2. you don't know where to find qualified people you need. Turnover will be high if you assume you need commodity devs and don't, for instance, invest in their skills (like teaching them minority languages if that's your thing).

If I see a company hiring for "python developers" or "java developers" at this point I absolutely know what sort of problems their codebases will have, because they're in the commodity market and treating development as a cost centre to be minimised. Which leads to lower salaries, which drives higher turnover.

It's all self-fulfilling.

by regularfry

6/3/2026 at 12:19:42 PM

Jobs and market have a huge factor of 1. politics 2. synergy

Almost the only reason that python is popular and people do everything with it is synergy. The only reason that javascript is eating the world and any web dev has to know it, and people do everything with it is synergy.

A big reason for C# to have popularity is because it's for Microsoft (politics).

These are just some examples. Being used doesn't mean anything.

There were and still are a ton of PHP jobs. You tell me, is it because PHP is a great language and solves our problems? No, because it has synergy.

If you're good enough, you can pretty much choose what language/framework you work in.

by yolkedgeek

6/3/2026 at 4:38:02 PM

you forgot the other side of the market which are the employers who have a business to run and they cannot limit their hiring to a small talent pool because advocates for that esoteric language said its da bomb.

by zuzululu

6/3/2026 at 1:45:20 PM

Give it up devs, we're all making WordPress sites now because there's loads of them

by escargot4000

6/3/2026 at 4:38:24 PM

but wordpress is not a language

by zuzululu

6/3/2026 at 3:25:30 AM

It's ok because I'm a hobbyist programmer!

by acdw

6/3/2026 at 2:01:42 AM

That gradient tho

by ai_fry_ur_brain

6/3/2026 at 9:17:58 AM 

    ;; This is real syntax!
    (loop for k being the hash-keys
          using (hash-value v) of hash-table
          ...)
Still lisp. Although the blog author has a point - clojure is probably cleaner lisp than common lisp.

I think the issue is heavily due to syntax though. Naturally the (())()()()(), but I think even aside from the (), the syntax does not seem super-efficient to me. Perhaps I have spent too much time with ruby and python, but it feels as if lisp is a legacy regression, purely syntax-wise.

by shevy-java

6/2/2026 at 10:17:34 PM

> The seq abstraction, for example, means I usually don’t have to worry about what kind of sequence I’m dealing with

Eh? That's completely lifted from CL (https://www.lispworks.com/documentation/HyperSpec/Body/t_seq...). Same for AREF/NTH, there's ELT.

Other than that, I agree, CL is baroque yet needs some hole filling here and there.

> Lisp: everything is a list

But that's wrong. Not even a little. Unless you mean LISP 1.5...

> Too much syntax

Funnily, I'm mostly okay with the new vector/set/hash-table literals, my big problem and that of some other people is the use of vectors in macros/special operators instead of lists. `(let [a b] ...)` instead of `(let (a b) ...)` is _not_ okay.

by BoingBoomTschak

6/3/2026 at 9:39:32 AM

> `(let [a b] ...)` instead of `(let (a b) ...)` is _not_ okay

it is however quite consistent, clojure uses vector form for most macros that require a "control" form before a "data" form: argument list in defn, names list in let, iteration descriptors in for, etc. you get used to consistency quite easily.

by midnight_eclair

6/2/2026 at 10:24:05 PM

I haven’t used clojure in quite a while but what’s the issue with (let [a b] …)?

Is (let (a b) …) even valid clojure?

by y1n0

6/3/2026 at 3:29:01 AM

In CL and Scheme, it's (let ((var1 val) (var2 val)) body...). So parentheses are used for grouping and function/macro application. In Clojure, parens are just used for application, so you have e.g. (let [var1 val var2 val] body...), or (defn foo [x] ..) or (cond testa 1 testb 2 ...).

It takes some getting used to, and I do wish Clojure would do something more like (let [[var1 val] [var2 val]] ... .. though of course then you'd have to figure something else out for destructuring.

by acdw

6/2/2026 at 10:47:33 PM

I believe it would be (let ‘(a b)), but I’m not sure if that’s valid or not. That’s how Racket does its version of defn

by everforward

6/3/2026 at 9:46:57 AM

[dead]

by draw_down

6/2/2026 at 11:43:32 PM

I’ve been using Clojure for almost 10 years and it still feels like a foreign language to me. I call it “parenthetical hell”.

by temporallobe