Clojure Q&A - Recent questions in Meta

Does Clojure have an anti LLM code contributions policy? Would it make sense for Clojure to adopt one?

Sun, 29 Mar 2026 13:14:25 +0000

LLM use appears to have a bunch of ethical and practical problems, the most pressing one seems to be the plagiarism that seems to be pretty excessive even for code and even when not baited:

Video clip of apparently a lawyer live demoing what seems to be Co-Pilot plagiasm

I don't know anything about law, but the lawyer at one point says: "This is a copyright infringement." I've also found this: https://www.twobirds.com/en/insights/2025/landmark-ruling-of-the-munich-regional-court-(gema-v-openai)-on-copyright-and-ai-training It seems to talk about "fair use" of AI model training.

Also see this high-profile incident: https://www.pcgamer.com/software/ai/microsoft-uses-plagiarized-ai-slop-flowchart-to-explain-how-github-works-removes-it-after-original-creator-calls-it-out-careless-blatantly-amateuristic-and-lacking-any-ambition-to-put-it-gently/

Also this field study that appears to be putting the plagiarism rate at seemingly at least 2-5%: https://dl.acm.org/doi/10.1145/3543507.3583199

This article mentions a study that apparently puts the plagiarism rate at 8–15% as a minimum for the easily detectable kind: https://www.theatlantic.com/technology/2026/01/ai-memorization-research/685552/

I don't know what this means legally, but at least morally and ethically this seems sad.

Apparently, some people in the Clojure space already spoke out against LLMs, but I wasn't able to find any anti LLM policy. If there was such a policy, I would expect it to be mentioned in the following places:

I simply wanted to suggest that perhaps the project may want to adopt such a policy.

Here are some other projects that have already done so: Asahi Linux, elementaryOS, Forgejo, Gedit, Gentoo, GIMP, GoToSocial, Löve2D, Loupe, NetBSD, postmarketOS, Qemu, RedoxOS, Servo, stb libraries, Zig.

My deepest apologies if there already is such a policy, or if I'm asking in the wrong space.

Why meta-data map is declared before symbol?

Wed, 05 Mar 2025 21:36:26 +0000

This is a stylistic thing, and I’m trying to understand design decision. It feels intuitive to attach metadata after the symbol since it naturally reads as: “define User, with metadata X.” But in Clojure, metadata appears before the symbol, why?

Clojure:
(def ^{:doc “doctoring”} user-id (uuid))
(defn ^{:doc “doctoring”} create-user [email] (db/create-user email)

As opposed to:
(def user-id ^{:doc “doctoring”} (uuid))
(defn create-user ^{:doc “doctoring”} [email] (db/create-user email)

Is it for parsing simplicity of the reader? Attach this meta to the next symbol?

Consider adding a redirect for old Jira links

Thu, 26 Oct 2023 11:00:53 +0000

Older documents have a lot of links similar to http://dev.clojure.org/jira/browse/CLJ-2438. Currently, following them leads to https://clojure.atlassian.net/browse/undefined, so all those old links have been pretty much 404'ed.

The new URL should be https://clojure.atlassian.net/browse/CLJ-2438, which seems like a very simple rewrite rule. Perhaps it could be implemented?

Artifacts / SHA256 updated on August 26th

Tue, 03 Oct 2023 19:38:50 +0000

Hello Clojure community

I'm one of the Java buildpacks maintainers and we recently discovered a discrepancy in the releases for this repository: https://github.com/clojure/brew-install/

The issue is that releases artifacts seem to have been republished / repushed after their initial release, effectively overwriting tags and artifacts attached to it; but since the paketo buildpack for clojure rely on SHA256 signatures to make sure the archive is the one that we expected, it basically broke them.

For example, let's take release 1.11.1.1347 as an example.

in the clojure/brew-install/ repository, we can sha256 the archive (shasum -a 256 ~/Downloads/linux-install-1.11.1.1347.sh) to 73a780bac41fc43ac624973f4f6ac4e46f293fe25aa43636b477bcc9ce2875de

Weirdly enough though, this release dates back to August 26 whereas the commit was done on May 31st

on the other hand, the Paketo team has a different sha for the same script

We believe the user named puredanger has mass-overwritten Github releases, potentially changing content of the published releases, on August 26th; the reason to think this is to look at this releases page where all older releases (<1360) were updated

We just wanted to make sure this issue was known and, if possible, would not happen frequently since it can break downstream redistribution channels, such as Paketo buildpacks. (we just updated and released to one of the latest clojure release, but users set on older versions could be impacted)

Thank you!

Could the syntax highlighting be improved?

Thu, 14 Sep 2023 10:24:29 +0000

The syntax highlighting for code blocks on this site is a bit broken / inadequate. If you look at the code blocks in a recent question of mine, you can see it pretty randomly applies colors, to the point of making some things very hard to read because it apparently considers # to be comment syntax.

By inspecting the DOM, I noticed that the system tries to guess at the language in the snippet and then applies syntax highlighting rules for whatever it guessed. It wrongly guessed cs, php and ruby for various code blocks in my question, so either the algorithm is pretty bad or Clojure isn't even supported.

Is there perhaps a way to specify which syntax highlighting to apply a la fenced code blocks in GFM I couldn't find? If not, I suggest to generally disable syntax highlighting if possible.

ERROR DATOMIC CLOUD S3 AWS

Sun, 11 Dec 2022 17:43:52 +0000

I'm trying to connect with the datomic cloud, but when I connect with the client I get the following error:
Execution error (NoClassDefFoundError) at com.amazonaws.services.s3.AmazonS3ClientBuilder/standard (AmazonS3ClientBuilder.java:46).
Could not initialize class com.amazonaws.services.s3.S3CredentialsProviderChain

[meta] Would Comments on Questions be possible?

Fri, 09 Dec 2022 17:57:14 +0000

One difference between this software and Stack Exchange is that the latter allows comments on questions, while this site does not (unless I'm missing something).

Comments on questions can be helpful (in my experience) to clarify things before posting an answer.

I'm not sure exactly what software is running here (is it bespoke? or something off the shelf?), but allowing comments on questions would be an improvement, imo. Maybe it's easy to add/enable?

Thanks again for all you do, this site is just a tiny part of the Clojure community, which is always so awesome and welcoming and is a great part of my life that I value tremendously.

how do i do clojure code highlighting on this site? triple backquotes don't work

Wed, 27 Jul 2022 11:13:00 +0000

`clojure
(defn my-cool-defn [])
`

in the above example i'm trying to tell the markdown engine that i want my code to be highlighted as clojure, but i get "clojure" being output as well. i am not sure my code is even in a code block, but it is formatted differently. is this a bug with this website?

Social cards for posts on this site

Sat, 21 May 2022 20:45:18 +0000

I just linked to a question on this site from Twitter: https://twitter.com/pappapez/status/1528112807278960640

I notice that the post doesn't get any image and preview (a.k.a. Twitter Card). The Twitter Card Validator is not happy.

I think proper social cards will help links to this site from platforms like Twitter to pop more in those crowded feeds. So I'd like to propose that is added.

Why is there no Clojure compiler targeting Python?

Tue, 15 Mar 2022 07:59:27 +0000

There are some GitHub repos that tried to achieve this, but there's no activity around them. There is also Hy, which seems to be inspired by Clojure, but for some reasons it doesn't want to be Clojure.

Why did clojure community stop participating in Google Summer of Code?

Mon, 25 Jan 2021 14:21:41 +0000

It seems to be no participation in Google Summer of Code since 2017.
https://summerofcode.withgoogle.com/archive/2017/organizations/5054104644616192/

Is there any specific reason for that? I think it might be just because no one participated in 2017 Clojure project.

I'm considering about applying for GSoC this year and I wish I could apply for a Clojure project.

Community Library+Coding+Standards from dev.clojure.org link is broken

Thu, 22 Oct 2020 22:34:51 +0000

On my team we linked to http://dev.clojure.org/display/community/Library Coding Standards for basic Clojure styling conventions, and I realized recently that the link is now broken. Is there a new place for this content?

Is Clojure a good first language?

Sun, 27 Sep 2020 16:10:25 +0000

I am new to programming. I have started to learn C++ and even some python
My background is Economics. I have strong quantitative background (Math and Econ) and I know STATA.

In general, I would like to use programming
(1) for ML/AI in economics topics+other utilities such as webcraping, and other data driven analyses
(2) for it, fintech matchmaking platforms

In particular, I just recently discovered I love programming. I am old (35) as a beginner but I have set a goal to become a fully capable programmer by 40...Hopefully I can learn 2 languages well enough by then.

If jobs opportunities are present then, I can switch careers although I still like my career path. I could always use my programming skills for either my job, a start up, or become a full fledge prgrammer.

Online research has led me to think that Clojure might be an excellent language to focus on because they say it is an excellent for rapid development (If I want to use it for a start up, lone developer), data-driven (econ and ML), and provide a path to be a great programmer.

My Apprehension is that Clojure doesn't seem widely used so might issues with doing ML projects with few libraries (compare to Python for ex), and future job prospects, etc...

Anyway, I welcome any insights/advice, tips.

Thanks in advance,
Baye

Can I learn clojure by using a mentor programm

Thu, 04 Jun 2020 19:50:14 +0000

Hello,

I remember I read some time ago about a sort of mentor programm where people learn clojure with a mentor.

But I cannot find it back.

Does anyone if it still exist and where I can find more info.

Roelof

Any good tutorials on clojure-walk ?

Sun, 23 Feb 2020 21:06:03 +0000

I want to develop a tool that ingests json into native clojure data-structure and then provides a jq /json-pointer like select/map/filter api or capabilities. I believe clojure-walk might solve this.

common source file shared between 2 Leiningen project

Tue, 08 Oct 2019 13:48:02 +0000

Hi,

i have two Leiningen project that compiles well, and worked well before sharing some functions in a common included file.
Both project runs on a tomcat server

First project create a .jar file used as a library for java code compiled from java source.
it has been created with:
lein new eu.oca.jclojure
and compile this way:
lein uberjar

The other project is a full clojure web application running also on tomcat.
it has been created with:

lein new compojure sidonie-admin

and compile with:
lein ring uberwar

the common file is included in source clojure code like this:

(load-file "src/sidonie_admin2/sidonie-common.clj") in the second project and in the first like this (and both compile without errors)
(load-file "../sidonie-admin2/src/sidonie_admin2/sidonie-common.clj")

The error occurs at runtime :

the problem come of the file having common definitions that is not included in the war file and probably not in the jar file and i have this error when running one project:
java.io.FileNotFoundException: ../sidonie-admin2/src/sidonie_admin2/sidonie-common.clj

and this error with other project:
Caused by: java.io.FileNotFoundException: src/sidonie_admin2/sidonie-common.clj (Aucun fichier ou dossier de ce type)

those are same type of error complaining about missing source file in JVM byte code !
a bit surprising ,i admit in case of error print stack trace needs some info to give line number of error.

so the question is simple, how can i share the common file between two projects and have no error?

best regards,

Damien

here is some output of server log:

08-Oct-2019 12:40:51.275 SEVERE [http-nio-127.0.0.1-8080-exec-8] org.apache.catalina.core.StandardWrapperValve.invoke Servlet.service() for servlet [eu.oca.ApplicationConfig] in context with path [/Sidonie] threw exception [org.glassfish.jersey.server.ContainerException: java.lang.ExceptionInInitializerError] with root cause
java.io.FileNotFoundException: ../sidonie-admin2/src/sidonie_admin2/sidonie-common.clj (Aucun fichier ou dossier de ce type)

at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInputStream.<init>(FileInputStream.java:138)
at java.io.FileInputStream.<init>(FileInputStream.java:93)
at clojure.lang.Compiler.loadFile(Compiler.java:7314)
at clojure.lang.RT$3.invoke(RT.java:320)
at eu.oca.jclojure__init.load(Unknown Source)
at eu.oca.jclojure__init.<clinit>(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at clojure.lang.RT.classForName(RT.java:2168)
at clojure.lang.RT.classForNam

...

un(NioEndpoint.java:1500)

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

and also:

08-Oct-2019 12:21:42.761 SEVERE [http-nio-127.0.0.1-8080-exec-11] org.apache.catalina.core.StandardContext.listenerStart Exception lors de l'envoi de l'évènement contexte initialisé (context initialized) à l'instance de classe d'écoute (listener) sidonie_admin2.listener
Syntax error compiling at (sidonie_admin2/handler.clj:32:1).

at clojure.lang.Compiler.load(Compiler.java:7647)
at clojure.lang.RT.loadResourceScript(RT.java:381)
at clojure.lang.RT.loadResourceScript(RT.java:372)
at clojure.lang.RT.load(RT.java:463)
at clojure.lang.RT.load(RT.java:428)
at clojure.core$load$fn__6824.invoke(core.clj:6126)
at clojure.core$load.invokeStatic(core.clj:6125)
at clojure.core$load.doInvo

...

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

Caused by: java.io.FileNotFoundException: src/sidonie_admin2/sidonie-common.clj (Aucun fichier ou dossier de ce type)

at java.io.FileInputStream.open0(Native Method)
at java.io.FileInputStream.open(FileInputStream.java:195)
at java.io.FileInp

Intentional communication with nudges, etc.

Thu, 12 Sep 2019 15:27:40 +0000

Background:
I'd like to think that ask.clojure.org was formed to have a more like-minded community as noted in this talk: https://devonzuegel.com/post/the-hard-parts-of-open-source-by-evan-czaplicki

Question:
Can it go farther and also implement the intentional communication techniques like trying to frame the intent of people asking questions, the background, the actual question, and buttons that nudge people to engage on collaboration and understanding?

Thanks in advance, and let me know if it'd help to restate the question in a clearer way.

Is there a slogan for Clojure

Tue, 06 Aug 2019 14:47:35 +0000

ALL programmers know this:

Life is short, use python

Is there a simliar one in Clojure?

What plug-ins were needed from Question2Answer?

Sat, 27 Jul 2019 14:26:09 +0000

app with a ton of plugins available that covered what we wanted to do.

Could you enumerate the plug-ins that were needed?

Can the questions from jira tickets revert from (link: ...) back to []?

Fri, 26 Jul 2019 18:33:47 +0000

I think this is a minor formatting issue, related to arg vectors and other binding forms in a lot of the original Jira text, particularly code examples.

For instance, [^double x] gets coerced to (link: ^double x).

Edit:

As in https://ask.clojure.org/index.php/3317/support-type-hinted-overrides-of-function-parameters and
https://ask.clojure.org/index.php/3326/cannot-create-anonymous-primitive-functions

I saw this pattern in the compiler tagged posts by jira, and divulged it may be an unintentional mechanical transform (no idea if it's widespread).

Is ask.clojure.org itself implemented and written in Clojure?

Fri, 26 Jul 2019 17:53:09 +0000

What is ask.clojure.org written in?

Is it a Clojure/ClojureScript project? Or does it use another language or stack ?