Show HN: Horizon – GPU-accelerated infinite-canvas terminal in Rust

37 points by petersunde 5 hours ago

Tabs, splits, and tmux work fine until you have several projects open with logs, tests, and long-running shells. I kept rebuilding context instead of resuming work. Horizon puts shells on an infinite canvas. You can arrange them into workspaces and reopen later with layout, scrollback, and history intact.

Built in 3 days with Claude/Codex, dogfooding the workflow as I went. Feedback and contributions welcome.

tekacs - 3 hours ago

This is fun! I switched to https://github.com/manaflow-ai/cmux for a while, but had to switch back to Ghostty due to its unreliability, high memory and CPU usage and a bunch of bugs.

This makes a lot of sense, but... it'd be great to allow pulling out of a canvas into a second canvas for those of us with multiple screens (you at least end up needing one window per screen).

In general it feels like... more structure rather than less feels like it'd be the smoothest experience. I'll play with your Ctrl+K shortcut and see if it ends up feeling like I can get everywhere that I need quickly.

But... nice work!

Note for jj users like me: you need to `git lfs pull` if you want to `cargo run --release`!

Update: No luck creating any 'shell' workspaces (it looks like you use GNU-only flags to script) – I'll push a fix once I find it.

Also: the AGENTS.md is wrong JFYI - it points to portable-pty, when this is using alacritty_terminal's tty (on rustix-openpty)

petersunde - an hour ago

Thanks for trying it! I totally forgot about multiple screens because I use multiple workspaces on an 8K screen.
Splitting across multiple screens shouldn’t be too difficult since Horizon already supports multiple sessions. I’ll try to get it working tomorrow :)

cedws - 2 hours ago

Spatial memory is really underutilised in computing.

When libghostty[0] releases maybe you could use that so you don't have to build everything from scratch.

[0]: https://mitchellh.com/writing/libghostty-is-coming

petersunde - 24 minutes ago

libghostty looks really promising! I went with Alacritty as the terminal backend because its core is written in pure rust.
tekacs - an hour ago

libghostty already powers quite a few alternate terminals:
https://github.com/Uzaaft/awesome-libghostty
This project uses alacritty-terminal, so it's also very much 'not from scratch', just using a Rust library to that effect.

ms_menardi - 2 hours ago

This is great! Two things I noticed immediately:

the settings window overlaps with the minimap.

I think it'd be neat if you could zoom? The reason I'd use this over a tiling window manager is to fit more terminals on a screen at once. I think if there was a capability like the Strategic Zoom in Supreme Commander (video: https://www.youtube.com/watch?v=9hJY7exr9KU) it would be much easier to manage many terminals at once, and take advantage of the infinite canvas.

petersunde - an hour ago

Thanks for letting me know about the settings/minimap overlap, I’ll fix that. And yes, zoom is on the list! I’ll implement it tomorrow. Just wanted to get the core working first without hogging the CPU.

hokkos - an hour ago

The last thing I want is the figma experience for my terminal

cadamsdotcom - 3 hours ago

Maybe I’m old but this sounds like MDI (multiple-document interface) of the late 90s.

Went the way of the dodo probably because it’s hard for non power users to grok.

But this is a power user tool - seeems like a fit!

bigfishrunning - 2 hours ago

I think MDI style interfaces went out of fashion because there were a lot of programs that implemented an entire window manager and then only really needed one window. This added a ton of complexity that wasn't needed most of the time, because window management is really a job for a different program.
- cadamsdotcom - an hour ago
  
  You’re getting it ;)

fritzo - 3 hours ago

I was hoping this would be an infinite length terminal view, like the opening backstory in Star Wars

sakopov - 2 hours ago

Will there be any built releases available?

petersunde - 38 minutes ago

Yes, though it’s still early days. You can install it from crates.io with cargo install horizon-ui or grab a prebuilt binary from https://github.com/peters/horizon/releases/tag/untagged-0e65...
Each commit to main also produces downloadable unsigned binaries in the GitHub Actions tab.

jauntywundrkind - 2 hours ago

Feels very Niri like, in a positive way. Niri's "scrollable" interface always has room to the right & down!

One of the Niri tools I built for myself is to let me insert a new row up top, to expand up. Thats afaik not super easy in base Niri, constraints the spatial growth some.

I'm pretty close to having some persistence of terminal windows, tmux, etc in Niri, with some tools to dump current state nicely. Doing an actual restore operation would be a good thing to build towards.