Show HN: A Tiling Window Manager for Windows, Written in Janet
31 comments
·May 20, 2025MisterKent
How does it compare to komorebi? I've been using it for about 5 months with great success. I'm a Hyprland user when I'm on my personal machine, but for windows Komorebi has let me keep my muscle memory and workflow largely intact.
agentkilo
I think these are the most obvious differences between the two:
* By default, Komorebi uses dynamic tiling, while Jwno uses manual tiling.
* Komorebi has workspaces, Jwno works with Windows native virtual desktops instead.
* Komorebi uses IPC and native system command line to send commands, while Jwno usually operates all by itself.
There are definitely other details that are important to you, but these are the things that immediately came to my mind. I don't run Hyprland so can't really comment on that.
ang_cire
Custom windows shells (I know this is just a window manager, but still) in the year of our lord 2025? This takes me back to the days of installing bb4win and litestep in XP. I'm a kid again!
insin
TIL bbLean [1] still works in Windows 11! Currently digging through my archives for my old BB4Win styles repository
pbohun
This is so cool! It's funny because open source devs are making Windows better while MS is actively making it worse. If MS removed all telemetry and AI (and restored win10 functions in context menus), I would probably move back to it.
I've recently started playing around with Janet, and it's a great language. I think it's inspired by Clojure and Lua, and somehow manages to be better than both (in my opinion).
agentkilo
> I think it's inspired by Clojure and Lua, and somehow manages to be better than both
This is exactly how I feel about Janet too. I don't think I have enough experience on Clojure or Lua to comment on them, but I got attracted to Janet almost immediately.
Working on Jwno also confirms my first impression on Janet: It's really a practical language. The tooling has some room for improvement, but the language itself can get things done - usually fast and easily.
sph
How’s the REPL/interactive editing story? I feel weird using a Lisp that is not as interactive as Racket, Scheme or Common Lisp. Running scripts from the REPL ain’t the same thing as C-x C-e an expression on a live program
cfiggers
Agreed on the need for better Janet tooling. I'm trying to be the change I wish to see with Janet LSP[0]. Issues and contributions are welcome!
pbohun
This is how I feel about Janet too, absolutely practical. So far it's been a breeze to write the little experiments I've done so far.
rich_sasha
I'm curious, did you find there were things that were easier to do because it's Janet/lisp-like language? Or you just fancied like using it (perfectly valid reason of course!).
I tried various lisp dialects, but I could never find the killer feature vs other languages I already use. And I can justify why I use these specific languages I do use, if that makes sense.
agentkilo
I find the REPL and interactive development workflow invaluable. A window manager is a long-running background service by nature, and has a lot of accumulated runtime states. The ability to peek inside and debug while the process keeps running helped me a lot when building Jwno.
I think Jwno's REPL module is so important, I specifically changed Jwno's architecture at one point to make it work.
aus10d
Janet looks really neat. And this project seems really cool. Windows DESPERATELY needs a more powerful built-in manager. It's ridiculous to use the mouse all the time.
Rasthor
One of the later PowerToys updates makes the first few steps in the right direction with "fancy zones". It's not strictly native windows, but still developed by Microsoft and adds keyboard shortcuts for all its utilities
90s_dev
> You can implement custom commands and hooks to trigger. It's even possible to call native Win32 APIs in your own implementations. For example, to always move a Notepad window to the (100, 100) coordinates on your screen(s), using the low-level SetWindowPos function
Great job. Looks really interesting and useful. And a fun excuse to write Lisp.
I really appreciate it when APIs give you high-level functionality but keep the door open to lower-level APIs when you really need them.
pona-a
What kinds of automation are possible with having a scripting language inside your WM, rather than Sway-style IPC? I heard the new Windows WMs were where most pure workflow advances happen, so I wonder if they can be replicated on Linux.
null
packetlost
This might be the coolest project I've seen using Janet yet!
bsnnkv
Jwno is great, agentkilo is kind, Lisp is magic :)
agentkilo
Thanks for the kind words! It means a lot coming from you :)
null
Hi HN!
I read[1] about Janet[2] some time ago, then immediately got impressed by the enthusiasm of its community, and by the language itself, so I started playing with it.
At the time I was searching for a tiling window manager for Windows, and unavoidably the idea of scratching my own itch with Janet got hold of me, so Jwno was born.
Simply put, Jwno is a keyboard-driven tiling window manager for Windows, scriptable with Janet. But since it has a complete Lisp runtime, and a thin wrapper library for Win32 APIs[3], you can certainly do much more with it.
I hope you'll enjoy playing with it as much as I enjoyed building it.
And yes, I use StumpWM on the Linux side, by the way.
[1]: https://ianthehenry.com/posts/why-janet/
[2]: https://janet-lang.org/
[3]: https://github.com/agent-kilo/jw32