Colin Fleming

Cursive 2026.2 is out! Support for IntelliJ 2026.2 and new syntax in Clojure 1.13 alphas. Lots of other bug fixes and small improvements. cursive-ide.com/blog/cursive-2… #clojure #clojurescript

Cursive 2026.2-eap3 is out. It's a bugfix release, fixing several issues from the tracker and many from the exception reporter. cursive-ide.com/blog/cursive-2…

Cursive 2026.2-eap2 is out, adding support for the new syntax in Clojure 1.13 alpha. cursive-ide.com/blog/cursive-2…

@lucasmeijer I vibeslopped up github.com/cmf/pi-foreach to help with this. It could be more ergonomic but I have been too lazy to fix it. In particular the file mode is very useful, sometimes I'll get e.g. a list of classes out of my IDE that need processing, or a list of files etc.

it's actually a double nested loop, as after 4 tasks orso, so much work has happened, the original analysis isn't so great anymore, so I redo the entire thing from scratch after an iteration of 4/5/6

lo and behold I am doing a loop. manual with /tree but still. 1st prompt is "find all places where the app has a list of all modules, and suggest how we can make that be modular and driven from modules instead". that produces a list of 15 things. I tackle each one with

Cursive 2026.2-eap1 is out. Support for the new IntelliJ 2026.2 EAP, important bugfixes for the Standard Clojure Style formatter, as well as other bug fixes and some QoL features. cursive-ide.com/blog/cursive-2…

@danielwithmusic Anthropic has really been burning goodwill faster than VC cash recently.

Developers as a group are generally intelligent, and Anthropic’s misdirection only works for about 5 minutes until people read a bit further about the impact of the plan. Now they’re annoyed about the change, and that you’re lying to them!

Here’s how I would have announced this: Starting June 15, the Claude Agent SDK, claude-p, CC GitHub Actions, and 3rd party apps built on Agent SDK (incl. Conductor and OpenClaw) will no longer share usage limits with Claude Code usage.

@borkdude I live in New Zealand so this is a pretty big deal for me. I basically only go to conferences when I can combine it with a family trip we might reasonably have taken anyway (e.g. visiting my wife’s family in Europe)

Any thoughts about flying to conferences and climate change? When do you justify it for yourself and when not?

@lucasmeijer What about strlen.com/lobster/? Looks very interesting, and aimed at your wheel house.

my love for c# is fading, but I do not love a new language yet.

The Apropos team were kind enough to have me on their podcast to talk about Cursive and get me to demo some things: youtube.com/watch?v=gHTe0j…

@thatdigitaldad That's a bummer. I suspect there's a lot of your target audience who would rather their kids didn't have phones, or want to delay it. Also, phone chatting sucks compared to desktop. Just to be clear, I'm not suggesting a desktop native solution, but this: support.apple.com/en-nz/guide/ap…

Hi Colin, thanks for reaching out. Sorry but I checked with my team and there is some complexity with trying to bring the app to desktop or Mac, and we wouldn't be able to support it at this time. It might be something we look at in the future as we grow, but for now I'd suggest an older device if possible? We don't require a sim card or phone number so a device just on WiFi works well.

@thatdigitaldad Any chance of letting us run Kinzoo messenger on Apple Silicon Macs? Should be easy to allow the iPad version to run there. We'd love to get our daughter's friend group on there, but she doesn't have a phone.

Cursive 1.14.1-eap1 is out, fixing a bunch of bugs and usability issues. Fixes to the REPL selector (including the ability to disable it entirely), testing and new interop syntax, and better comment formatting. cursive-ide.com/blog/cursive-1…

Cursive 1.14.0 is out! Inline evaluation results, customisable to create data UIs in your editor. Many bugfixes, support for IntelliJ 2024.3, better REPL command management, and a Reformat Form action for pretty printing forms. #clojure #clojurescript cursive-ide.com/blog/cursive-1…

Cursive 1.14.0-eap2 is finally out! This release contains the customisation for the inline evaluation results that I demoed at Heart of Clojure and the Conj, as well as lots of bug fixes. cursive-ide.com/blog/cursive-1… #clojure

@RealGeneKim Alex Miller's excellent talk from the conj (youtube.com/watch?v=VBnGhQ…) had the stats from this year's survey. @pappapez and I are neck and neck!

Oh, here's the graph showing market share of coding environments for Clojure, from the State of Clojure Survey 2023. #1: emacs #2: IntelliJ / likely Cursive #3: VS Code / likely Calva, Clover, etc surveymonkey.com/stories/SM-_2B…

For those of you who are like me, doing everything you can to not get sucked in by election coverage today, here’s a writeup of an amazing talk about creating tools to leverage LLMs inside an IDE! This is such a fantastic talk by Colin Fleming (@colinfleming), author of the fabulous and indispensable @CursiveIDE plug-in for IntelliJ — this is one of the most popular editing environments for Clojure programmers, which I use on an almost daily basis. He gave this talk at the Clojure/conj conference two weeks ago — it was an experience report on using LLMs in his development process, and likely hints at how LLMs will be integrated into a future version of Cursive. It’s such a fantastic story, because he talks about problems he faced developing and maintaining Cursive, and specific ways LLMs helped, and the challenges that anyone creating dev tools using LLMs will inevitably face, with lessons that are applicable to anyone using LLMs. According to State of Clojure Survey 2023, Cursive is the #2 development environment for Clojure — behind Emacs, and ahead of VS Code. (Personally, I am so grateful for Cursive — I attribute it to having such a wonderful immersion into Clojure in 2016. I’m pretty sure it would not have been so joyful, so quickly, if I had to relearn emacs at the same time!) His story starts with describing how, earlier this year, JetBrains (maker of IntelliJ) started to force plugin developers to migrate away from Java threads to Kotlin co-routines — this is a major shift because since the very first version of IntelliJ in 2001, threads were the primary concurrency primitive. This affects almost every plugin developer: "Intellij is an extremely asynchronous system for performance reasons." "JetBrains is basically telling me that a lot of my [plugin] code is now legacy... The use of Kotlin is becoming more and more required... There is no way we can express proper structured concurrency and cancellation in Java. So the writing [on Kotlin] has on the wall for a while." Enter his problem statement, which he needed to figure out how to solve: "I now have 10 years of Clojure code... About a third of it, about 35,000 lines of Java code, is mostly legacy obsolete stuff I never touch these days. There's about 35,000 lines of newer Kotlin code, and there's about 35,000 lines of Clojure code as well." "I now have a problem. I have 10 years of Clojure code, and I don't want to spend another 10 years rewriting it. And this is where LLMs actually turn out to be amazing." He discovered that LLMs excel at code translation. "This shouldn't really be a surprise. The original 'Attention Is All You Need' introduced the transformer architecture. The example that they used was a [human language] translation problem. It was translating natural language rather than computer languages, but it's a very similar problem, and they're just astonishingly good at this." Fleming translated the Python Difflib library to Clojure this way, to support diffing and patching. (!!) He's also translated other Python libraries, such as Pydantic specs and AI API libraries to Clojure. "It also works in the other direction as well... I've been working a lot with AI APIs recently, so I've been using all of the tooling around AI, which is in Python. So a lot of the client libraries have Pydantic specs for the APIs, and I can just give those to the LLM and it will give me malli specs back." [Malli is one of the popular run-time schema/type checking libraries in Clojure.] (I think this is very cool. I’m a huge fan of the Guardrails library, which annotates Clojure functions to look more like TypeScript.) "These translations are never exactly perfect, but if I had to spitball a number, I'd say they're like 95% of the way there." So enter his initial use case: translate an entire namespace of Clojure code into Kotlin code — he can now do that 30m to 2 hours. @colinfleming: how much time do you think this saves you? i.e., how long would it have taken you without LLM assist? Source: youtube.com/watch?v=oNhqqi… 1/??

@RealGeneKim But depending on my use case, that might be ok! If I'm trying to build something I just want to work, then it makes total sense, because I really *am* a product manager then. But I think that for a lot of software devs, that's not true, and the intellectual puzzle is the fun bit

Fleing showed a slide showing this Reddit post, which was heart-breaking, even if it doesn't resonate at all with my own experiences with LLMs. To summarize (but please read the original post — it's amazing.) • The post author is a 3D artist at a small game company with 10 employees, where the art team consists of two people creating 2D sprites for mobile games. • Since the release of Midjourney v5, the author’s job shifted from 3D art creation to AI prompting, Photoshop editing, and implementing images generated by AI. • The author originally became a 3D artist to sculpt and create in 3D space, using personal creativity and hands-on skills, which feels lost now. • The boss sees AI as a cost and time-saving tool, with character creation now taking only 2-3 days instead of the previous several weeks required in traditional 3D modeling. • The author knows and feels extreme guilt that their “art” is stealing content scraped from other artists without their consent, and it's better than what they could have done without the AI. • The author’s previous skill advantage, especially in shape, texture, and rendering quality, no longer secures job security, as AI produces comparable or better results. • The author feels grief and anger over losing the chance to use their own creative energy and is torn between staying with the team or leaving the industry due to AI’s impact on their role. • Leaving the company feels daunting, as the author doubts job conditions would improve elsewhere in the game industry, amplifying a sense of dystopia. Contrast that to the way I feel about using AI: - it pushes the frontier of what I could do without it - it makes the work more fun - when AI is not available (say on transoceanic flight), I'd just rather not code (And with open source, the ethical issues are mostly absent.) reddit.com/r/blender/comm…

@RealGeneKim At the time I was *really* into the details of optimising assembly, something I haven't thought or cared about for years. But I think the move to LLMs feels different. If my job is more like a product manager, I'm not sure I'd enjoy it so much.

@RealGeneKim There are some levels-of-abstraction arguments here. A long time ago I wrote a fairly complex game for my Acorn Archimedes in ARM assembly code (!). When I got a PC, I then ported it by hand to x86 assembly code (!!!). That is insane to me now, but at the time it made sense.

@RealGeneKim For me of course, since making a beautiful table armed only with a chisel is firmly in the insurmountable category, the CNC means that the task is at least achievable. And if my goal is just to have a table, I'll be really happy about it because the process isn't so interesting.

@RealGeneKim I think AI is going to expose the fact that, sadly, many developers in many jobs are almost completely unmotivated by the goals of the companies they work for. If the pleasure of the process is removed, then I think it's going to expose that in awkward and uncomfortable ways.