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Because of your multiple "I am tired of saying this, but this text was written by me and not an LLM" in your blog posts, I want to tell you that I read it word for word. :D I know this comment adds not much but I felt it needed to be said.

I'm from the KDE project, and have been working on a new frontend built on libghostty-vt to hopefully one day ease our maintenance burden.

It's been a quite smooth experience, and I remain very excited about the lib. I believe you are successfully setting the standard. Big congrats for your 1.4.0!

Thank you for your work on this. When I was working on neovim core and started dealing more and more with the edge cases of libvterm and terminal emulation in general, I had the same thought "we should just have a gold standard library for this." But that was 6/7 years ago (2019) and a lot of stuff happened in that interim unrelated to engineering that demotivated me from pursuing it.

Periodically, I would run into TUI issues and think "I should just finally do it," especially around wanting to replace tmux in general. But I knew from experience the long tail of annoying issues for terminals that it's more time consuming than it appears, and so I again never bothered.

Thanks for the good work to raise all boats :)

I tend to move away from terminal emulation towards GUI when I can (and using custom remote protocols somewhat inspired by arcan), but TUI is still useful for a while. I actually had a need for a good terminal emulation library for the fallback TUI/pty attachment for non-gui programs for my supervisor, so I'll try out libghostty.

libghostty is brilliant and I'm very glad it exists. ghostel in Emacs is completely brilliant and so fast compared to anything else, a wonderful project fascinated by libghostty. another i might mention is zmx [ https://zmx.sh/ ] - process persister (detach, attach) with panes, tabs, hijacking the terminal. i always end up using tmux just for persistence and then am frustrated I can't remember how to copy etc. zmx has more features than some things of a similar nature and my understanding is that it's able to be taking advantage of libghostty things.

(a couple of us working on packaging libghostty and ghostty proper to for Guix at the moment )

Is it feasible to implement the libvte surface on top of libghostty? Might be interesting as a drop-in replacement.

As a fairly recent ghostty user I was surprised with how quickly it became my default terminal. Very smooth experience so far.

Thanks for the work on getting libghostty 1.4 out! :D

Wanted to add too that I can't wait for xterm to eventually support libghostty, you've been super supportive providing feedback!

https://github.com/xtermjs/xterm.js/issues/5686

Agreed on the value of libghostty. I switched from vterm to ghostel recently and it's solved some refresh issues I previously had with vterm when using CLI coding agents in emacs.

> Libghostty now builds and is tested (in CI) for: [...] freestanding (i.e. direct on hardware with no OS).

That's really cool, but I'm drawing a blank; what's it used for? Embedded terminal something?

Just wanted to say thank you for all your contributions to our industry, Mitchell. I love Ghostty and your vision here, and evangelize it whenever I can.

It's a pleasure reading your posts.

Maybe I’m just dreaming here but how far off is libghostty for Linux consoles?

Awesome, great going Mitchell! And Ghostel, which I'm hearing of for the first time, sounds very exciting.

Thank you for Ghostty! I've got an insane fork (AI generated) that uses variable width fonts and then does math so columns (like in top) still line up!

Any interest in moving console typography past the 80's, since computers are fast now?

Absolutely incredible. You've convinced our team to start getting to work in Zig and we're loving it!! Thanks for all you do

I know it’s been said elsewhere ITT, but thank you for making and supporting Ghostty!

Any plans for Ghostty to have the history of the terminal window reloaded on restart? Like the Mac native terminal app does? I am a heavy terminal user with a lot of tabs open, and after I restart the computer for whatever reason, I would like to have my terminal(s) as I left them.

Thank you for libghostty! I'm using it for my own terminal on Windows. I'm quite pleased with it

Great stuff! If it wasn't for Rex I'd still be using Ghostty daily

Aha, I wondered why the JetBrains terminals had become so much better recently. Didn't realize they'd made the switch.

But could it do two rows of tabs?

Thank you for making Ghostty, it’s a pleasure to use it everyday for work :)

Is the launch timed for Halloween parties? Good job team + community!

What are use cases of libghostty? Is it for building things like the terminal inside VS Code or any other such GUI application?

If I don't want to use the wave of "venture backed ghostty wrappers" for remote mobile coding similar to Claude Code remote, what options do I have? Any plans for a first party remote solution that's not SSH?

Isn’t it written in Zig? Not sure how that is “highly portable” compared to C

> And at scale I've proven 10,000 active (input/output happening) terminals on a Linux server with 4 cores and 8 GB of RAM.

When you say you've proven, are you hinting at use of formal verification?

terminal emulation keeps playing a central role in "computing" not withstanding it being an ugly prehistoric crocodile. Do you ever envision creating something modern, without the warts and with a design that incorporates half a century of lessons-learned? Something that fills this need but in a more elegant package? I'm asking because you're one of the few people that seems well-positioned to make a clean-slate replacement

I personally avoid using the terminal as much as possible b/c the whole things feels very archaic/fragile/baroque - but the central idea seems great and I'd love a modern take on it

the web version powers our quickstart via a cloudflare websocket and some custom patches (only on desktop): https://hotaisle.xyz/quick-start

it is all open source: https://github.com/hotaisle/hotaisle-website

Why is libghostty better than alacritty?

Although not necessarily advertised as such, I've been successfully using alacritty in several projects injecting terminals into things both serious and silly.

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I'm super excited for you and this, but this is mostly a highlight list of who is using your library. I was kind of excited to read about the actual changes to the library but I suppose I can go read the changelog on my own.

How have I not heard of hints mode before, that is amazing. Thanks for pointing it out I need to go remember some new hotkeys now.

Yeah this is what is keeping me from using ghostty. Unfortunately I think that discussion is dead and no one agrees on the design of the three or so separate parts. I maintain a fork with quick select for my own purposes but I can’t use it at work.

Oof, I've never heard of that and it sounds amazing

Hints Mode, yummy. That would be nice.

See like something that can be handled by the multiplexer?

KDE guy here.

Konsole is a fantastic and very mature terminal emulator, but it does have some real gaps that reveal its age.

The Qt toolkit that most KDE software is based on at some point introduced a next-gen toolkit-within-a-toolkit called Qt Quick, which most of our newer apps are written in. However, in its library form Konsole can only be embedded into apps that use the old gen toolkit. This is a real impediment to some efforts.

The old gen toolkit also typically doesn't use Vulkan or OpenGL for rendering (the new one supports both), and so Konsole's terminal renderer doesn't either. Konsole's real-world performance during use is arguably just fine, but it does leave a lot of performance and battery life on the table.

libghostty also has somewhat wider support for newer stuff like Kitty protocols, even though Konsole certainly trumps it in support for older stuff (like sixels).

There's some other shortcomings to Konsole that are not inherent to the technology, like accessibility support not quite being where it should be.

And while the default UI is, in most distros, OK, there sure is a lot of spiderwebs and spacebar heating lurking in the settings dialogs (of which there are strangely many). It's also a bit dated vs. our HIG at the moment.

Which is to say, these projects can and do have a point, especially if they provide a nice library instead of hoarding all the good to themselves.

A couple of annoyances I've had shipping CLI apps to Konsole users:

1. By default, Konsole disables OSC8 link support. Users can enable it manually, but you need to ship fallbacks by default since otherwise the default users will have a broken experience. Ghostty, Kitty, WezTerm, etc all ship working OSC8 support out of the box.

2. No built-in Nerd Font support, so if you want to render icons, you need to tell your users to set up a patched font or else have fallbacks. Ghostty and WezTerm ship built-in Nerd Font fallbacks if your configured font isn't patched.

That being said Konsole is much better than most emulators. iTerm2 is not bad, although it lacks Symbols for Legacy Computing Unicode support (which all of the above have, including Konsole, and which is very useful for drawing prettier terminal UIs). The worst by far is Apple Terminal, truly the IE6 of terminal emulators.

1) Personal preferences: different terminals come with different defaults, some people do not want to tinker with the settings, so they just stick with whatever immediately clicks.

2) Technical curiosity: some people probably started their own terminal project just for the fuck of having made their own - and they eventually gained a userbase.

3) Feature set: Most terminals implement most features these days, but at the time these projects started, you'd have a feature matrix between features and terminals because most terminals lacked some features; so people would pick whatever suited their needs.

Personally I've been using kitty for years mostly due to 3), at the time I chose my forever terminal, I evaluated like 12 different ones, and kitty was the only one that covered most of my needs without feeling like it suffers from random quirks, and I like that it has built-in terminal multiplexer (a'la tmux) and emoji picker.

The terminal ecosystem needs to change, and these terminals support a lot of cool features. Ghostty's pure reusable terminal state machine being a source of truth, Kitty graphics, Wezterm and its mux domains & lua config, lots of cool ideas there.

Having having an industry player like hashimoto's superlogical driving terminal features is the extreme version of that

I assume that this depends on your computer/GPU/GPU driver.

I have used Konsole for many years and I have used kitty for about 2 years in 2024/2025, then I have switched to ghostty around the beginning of 2026.

At least in my computers (with NVIDIA GPUs and Gentoo Linux), kitty was many times faster than Konsole and Ghostty even faster.

Moreover, in the now somewhat distant past when I was still using Konsole, it did not have some font rendering features that I desired, but that might have been solved meanwhile.

A reason why the terminal emulator speed is important for me is that I frequently compile big software projects and I find it unacceptable for a compilation to be slowed down by the low speed at which the compiler output is displayed on the terminal window, which happened frequently with all terminal emulators older than kitty and ghostty (I have always used CPUs with enough cores so that compilation itself is very fast, so the older terminal emulators become the bottleneck).

I know for many folks they like the fact that it is cross platform (works on mac/linux) etc and gpu acceleration which is really nice to have.

For me: it doesn't really "bring" anything more than what I expect from a terminal.

In Mac, we had the default terminal app which has some problems with TUI apps and other small issues. iTerm2 is the replacement that most users use, but it become too bloated with useless features and AI, while it was hard to keep a good config file that I could share between devices. Ghostty was a sane mid-term for me: a good and modern terminal, with a simple config file, maintained by someone that I trust (Mitchell Hashimoto) and only that.

About Linux: I don't use Ghostty in Linux because I'm comfortable with Konsole.

There's always gonna be something that's better, faster, bigger, badder, stronger, thicker, firmer, etc., and terminals really aren't one of those things where I am interested in exhaustively testing all of them to find the truly greatest one. A terminal is also one of those things where if you find one that is perfectly adequate then there's little motivation to even bother using trying one. And there's the whole "devil you know" aspect. The only reason I rarely try a different terminal is if the stock terminal on whatever OS I'm using lacks some basic niceties that should be expected in the year 2026.

I like Ghostty because I find it both fast and configurable, and it's multi-platform without treating macOS like the red headed step child. I also appreciate how its configuration is text-based, which I prefer to someone's opinion of how a configuration GUI should behave, and I think it's good the developers aren't wasting a second of their time thinking about a configuration GUI.

I use Linux at home and Mac at work. I use Ghostty simply to have the same terminal on both systems.

I don't think Konsole is actually faster than Kitty or Alacritty. Kitty is really nice and an innovator in a lot of terminal standards. It's also non-commercial and not related to any sort of startup (not that Konsole is either). It's definitely my first choice of the bunch, followed by Alacritty.

For me it's simply that iTerm2 got really fat over the years, and Ghostty was a nice and slim alternative - plus it has one of the better Kitty Graphics Protocol implementations which is fun to tinker with. e.g.: https://github.com/floooh/chipz-kitty (needs zig-0.17.0).

I tried a bunch of terminals and ended up switching back to xfce-terminal, fastest I have tried by far. (It's just the default that ships with my distro.)

Actually I think xterm was even more performant, but the eye sore wasn't worth it for me.

For me, the main reason to use Ghostty is simply that mouse support works right out of the box. In Konsole clicking a spot to move the cursor only works if you're using Bash. While it also works with the Fish Shell on Ghostty.

To add to the other good points made in sibling comments, MacOS has butchered fullscreen to the point where some of us depend on MacOS terminal emulators having the "non-native fullscreen" config option. Personally, Ghostty does the best job supporting my preferred terminal environment of non-native fullscreen with tabs that works with an auto-hiding menubar and the camera notch.

The other day I was able to click on Ghostty, then open Gnome Terminal, type a command and run it before Ghostty had finished loading.

It works well, that’s my only requirement. I could ask you the same, what’s the point of Konsole, what value does it bring?

Kitty is really nice, a programmable terminal that does everything I want, GPU rendering, etc. Haven't used Ghostty yet but one of its advantages is libghostty, modern terminal emulation as a library.

> libghostty: a cross-platform, minimal dependency library that exposes a C API so feature-rich, correct, and fast terminal functionality can be embedded by any application anywhere.

Oh the author actually posted about it just now in rich detail. It's pretty exciting for people who spend much of their time in the terminal.

iTerm2 feels overwhelming to me. I think the default Terminal.app is good enough.

>I still don't understand the point of Ghostty, Kitty, Wezterm...

WezTerm can run on my Mac but give me a native GUI experience of a Wezterm session on my Linux workstation. It's like tmux, but with a native GUI experience including mouse click-drag selection that doesn't pick up "window" borders.

That alone is what is keeping me on Wezterm, since I get a native experience on some terminal sessions I access remotely on my macbook but then can switch to on my 30" screen when I'm at my desk.

for terminals I personally am using kitty, but libghostty is great and powers ghostel in emacs which is amazing. Also note if you start trying to look at unicode correctness, in my experience ghostty is in general the best among all alternatives.

> Konsole is way faster than any of those on my computer and it has all the usual suspects I'd expect from a modern terminal emulator.

Same boat here, though I also get to enjoy some of the benefits of libghostty, via ghostel in Emacs. Ghostel is noticeably faster when there's a lot of output being dumped, but I don't often need the speed and use it only because it's integrated rather well into the rest of my Emacs.

> tmux -CC integration

If you can stomach Emacs, there are at least two packages that implement this, one via eat and another via vterm, though none via ghostel just yet. Shouldn't be difficult to port, though.

I don't know about the others as I used Terminal.app on mac since Panther, but Ghostty has been a pretty good upgrade, at first offering 24-bit colour which Terminal.app didn't have at the time of its release. I also like the shell integration such as easy selection of command output. I don't ask much from a terminal as evidenced by using Terminal.app for almost 2 decades, but Ghostty has not once been an issue and is 'invisible' to me.

vouch this comment since this is a pretty common question people have, I don't believe it should be dead.

The advertised point is it needs zero config to work outside of the box. For example nerd fonts are included by default whereas you need to install them if you are using let’s say iterm2.

The point for me is each one can have ten or so claudes, so any one crashing doesn't take down all the claudes ... and I don't have to learn tmux.

Can konsole do the fancy shader and inline images? I think that's all that distinguishes the others but I may be overlooking things.

I can use Ghostty and use the same featureful terminal on Linux and macOS.

I also hate configuring Konsole, most KDE apps for that matter. Being able to have a plaintext configuration file I can keep in my dotfiles is way simpler.

tmux control mode (-CC) is the killer feature I'm waiting to land in ghostty

Konsole is not gpu accelerated and is several orders of magnitude slower as a result than those that you listed?

The acceleration is the primary point.

I don't know Konsole, but kitty have tons of features other "plain" terminals lack. It's not just about speed (which I never got the obsession about either)

Ghostty is so much better than iTerm2! Don't get me started...

I was sceptical for decades as well. But they are amazing - no more closing the xterm by mistake. I'm using those because I wanted for example a single window with THREE consoles open at once AND being able to handle some ANSI crazy theming.

Xterm failed me :( Tabby just works.

cute little mascots

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Lots of things bother me about my terminal emulators, and it's almost always in the category of "things don't work right". It's never "I wish my terminal emulator ran faster." Ghostty seems hyper focused on speed, with the negative side effect that compatibility breaks - in practice. I get that it's following all the newest standards or whatever it's doing, but in reality it always needs custom setup to work right. And for me the net effect is that it's always creating problems, not solving them.

I have a fix in my fork: https://github.com/ghostty-org/ghostty/commit/95c7fc322802a6...

Inspect + build yourself

I was really hoping a fix for this would be included in this release.

If you’re fine using iTerm just use iTerm. In my case I used iTerm for years and kinda liked it, but not completely. I’d been looking for an alternative for years but couldn’t find one I like (Alacritty doesn’t support pane splitting, Wezterm has full code config which I hate, Kitty doesn’t look good on Mac, Terminal.app is dog slow…). Ghostty just fits my needs pretty much exactly.

I am an iTerm2 user but I find its .plist config file a lot anachronistic and, if I may say so, quite absurd. I have tried too many settings and I still struggle with keyboard inputs getting trapped wrongly, lost, et cetera, the warnings that appear out of nowhere and I notice was wrong. But iTerm2 is the only terminal app that looks the best on mac (even better than the Terimnal.app itself) and somehow sits naturally with everything else around. I am sure for a lot of terminal users it might not even the last concern but for me it is. I tried Ghostty but I just couldn't like it. Kitty won't even be a consideration for many reasons (one is better off not discussed here). cmux is indeed quite good but it has become a HYDRA and will keeps on growing in every direction. iTerm2 would do great to keep the outer clothes and possibly adopts the base of something else. It isn't particularly snappy either. I moved back from Ghostty to iTerm2 even though I felt usage wise Ghostty was suprior. Ghostty just felt out of place.

I'm also very reluctant to switch and will not switch anytime soon. I have small compact tabs which I color code dynamically with iTerm2 and also custom profiles with custom keyboard keys overrides by program and directory. So the "harness" around the terminal is more feature rich with iTerm2.

These kind of features are not available in Ghostty in this form.

And about backups in iTerm2: Just do an export and maybe also a backup of your profiles. So that works.

I also do not care about a "super fast" terminal... my iTerm2 is fast enough for 99% of use cases for me.

There is no reason. I switched from iTerm 2 and while Ghostty is a lot faster and lighter, it has occasional rendering issues and does not detect URLs as well. It also doesn't have tmux control mode which I really liked.

I quit using iTerm 2 because of the AI features. Ew.

I don't think anyone is trying to convince you you should use Ghostty over iTerm2. It's a technically excellent terminal built with an incredibly rigorous and well thought out guiding philosophy and a remarkable amount of passion. Nobody cares if you want to run it or not.

One reason is portability if you use (or plan to use) desktop Linux

I find iTerm2's constant prompts to update to be annoying. It has also crashed on me a few times. Lastly, I also prefer ghostty's text-based configuration.

For me even just the config format is such an upgrade that it was worth switching. Just a simple text file I can backup anywhere and actually read without clicking in a tabbed GUI where I never seem to remember what goes where. iTerm2 still has that weird thing you have to export right?

Good point, maybe letting talented people get FU money is good for humanity?

Very likely due to ghostty setting TERM to xterm-ghostty and your destination not recognizing it. Quick temp fix is using the wrapper (ghostty +ssh), see <https://ghostty.org/docs/features/ssh>. More permanently, copy terminfo to the remote machine, see <https://ghostty.org/docs/features/ssh>.

Did you configure emacs to interpret a rapid temperature rise as CTRL..?

https://xkcd.com/1172/

I don't understand complaints like these, the tool is open source, fork it build it yourself and you will never have to update it. You really have the power to maintain your own tools.

btw I used iterm2 for years as well and sometimes tried others.

I now use ghostty it’s faster definitely. Yes it has some quirks which is hard to overcome as a iterm2 user. But I could live with it. I think ghostty is basically also the only alternative to iterm2

I used iTerm and iTerm 2 for almost 20 years before switching to Ghostty full time in 2024 with minimal fuss besides the muscle memory of "cmd+space ite" switching to "cmd+space gho" to launch it!

Do you have specific examples of usability issues?

Same. Windows with WSL at work and personal Linux. Run wezterm on both with shared config. It’s amazing.

Oohh. I hadn't heard of tty7. I like its goal.

Unfortunately, it seems to be doing something strange - I use vi-mode with nushell and it renders every character I press - even in normal mode.

I might keep an eye on it - hopefully they improve whatever they're doing with local echo.

I should say - I currently use WezTerm for exactly the feature tty7 advertises about session support. Even remote sessions.

A bit dismissive, I'd say it's a defensive statement because pretty much everything posted on the internet with a comment system will have an "Is this AI? I can see from some of the pixels and having seen quite some AI in my time" type remark.

I'm using xterm.js with the canvas/gpu renderer in my app, driving these modern coding agents that seems to use every features in the book of terminals and it's perfectly fine.

The dom renderer is also perfectly fine, just needs a little bit more careful CSS to make it look right with some of the fancy line art.

I do use ghostty and it's alright. It's required for some rich TUI ai seems to be pumping out. Otherwise I prefer tilix and the default gnome terminal, but it might be just because of years of habit.

There's a third party appimage, still on 1.3.1 though: https://github.com/pkgforge-dev/ghostty-appimage

Normally not a fan of appimages, but this group focuses on making higher quality versions that make very few assumptions about the host system and work almost anywhere. While also prioritizing speed, small sizes, and up-to-date dependencies.

you should be able to get it from your system package manager or flatpack. linux is annoying here because it's a GUI app.

iTerm on linux would be the dream! I wanted to switch to ghostty for the performance and sane defaults, but it’s just not feature complete with iTerm yet

You're thinking of Ghost not Ghostty

same, hoping for an official build

window.zig: widget.addCssClass("no-border-radius") when no compositor is detected seems like it should be preventing this, but it's clearly not working.

Same boat here. This makes me think I’ll switch to ghostty soon

How’re you feeling after the change?

Got the Rex beta but haven’t looked at it really. I made a custom Claude code harness that is orchestrated by go CLI Claude wrote for me and that uses herdr for session management. Probably there’ll be something interesting I can do with Rex in the future as an alternative

Kitty is so awesome. I'm writing (well, as much as anyone writes) a MUD that models a decent part of Tokyo at 30-60fps over SSH at reasonable resolution (that's the dream, at least). I'm shocked at how fast I can render a big complex 3d environment, in the terminal.

Any source/screenshots?

Probably something to do with Zig. Zig changes so quickly that if you're not using exactly the compiler that they are using, it's unlikely to work.

Here's a delicious meal we prepared for you. We don't recommend you going to the kitchen and trying to prepare it all over again.

..but you can!

Nothing controversial here.

What does it have over WT worth waiting for?

> Escape codes are the new html for browsers now called terminal emulators.

Not really and that isn't a good thing in the long run.

There should not be any more complexity in a terminal emulator that will just lead attackers to craft RCEs exploits to your terminal to steal your secrets on your computer just because "Its cool" and has hundreds of escape codes.

I've been working around it by setting my keybind to

  gdbus call --session --dest com.mitchellh.ghostty --object-path /com/mitchellh/ghostty --method org.gtk.Application.Activate '{}'

I had a similar problem maybe a year back. I've stuck to Foot since. I've got a new laptop now though and might be worth giving Ghostty another spin.

What did you settle on?

I like foot but don't mind waiting a few tens of ms in exchange for kitty's graphics.

I use suckless terminal because the entire terminal is 4888 lines of C (including comments). Builds immediately. Starts immediately. Does everything I need it to do.

Have several running; resident set size between 10MB and 19MB.

https://st.suckless.org/

Start with the person that is instrumental in this - Mitchell Hashimoto - you probably use products built on top of or with his tooling somewhere in your daily life already without knowing it. https://mitchellh.com/

I suspect you're getting down voted on this as it feels like this is a failure to educate yourself on something that feels like it should be relatively easy to do so in less time than it took to type your message.

Wait until it is packaged for your distro. It should be vetted then.

If on Mac/Win, you should be used to trusting notarized apps after a cooldown period.

any idea why people downvoting a legit question? what's wrong with them ?

Reply and then downvote, but silently downvoting ? not a real men, hiding behind their keyboard :)

"My Ford used too much fuel on one of the trips, so I switched to Volkswagen and today, on a another trip, it used much less."

Sure enough, one minute later he posted a comment lol

Kitty can do that now, though.

Truly odd to see this comment. For me, mitchellh defines the moderate position on agents in coding, I mean that seriously: not occupies it, defines it. I’ve raised this point in discussions and others get what I mean without explanation. He’s better known for a mitigation to LLM downsides (vouch) than for making conspicuous use of them, and insists on human-only prose in issues, PRs and ‘real’ documentation (which I firmly agree with btw).

He also has a blog post and some tweets about how they can find and fix difficult bugs, and otherwise are capable of solving hard problems now. Well, they can.

Is that the LLM bug to you?

tmux, baby!

I doubt that very much.

An LLM may be fine to implement quickly an application that more or less works, but I have not seen any evidence that any of them is able to write well optimized code, whenever the application is not just a duplicate of something older.

Ghosstty and a few other newer terminal emulators are not only lightweight, but they also implement very fast GPU rendering, which is one of their important advantages.

So not only their set of features matters, but also the achieved performance.

Of course, one could use an LLM to write a very fast terminal emulator, but for that a competent programmer must be included in the feedback loop, which would require many iterations and running benchmarks and emulation conformity tests. It cannot be done by vibe coding with a prompt like "write a lightweight terminal emulator".

Here's one such project: https://github.com/Dicklesworthstone/frankenterm

However, it is more focused on multiplexing.