> We build Claude with Claude. Our engineers write code with Claude Code every day
well that explains quite a bit
well that explains quite a bit
> Unable to process - no bug report provided. Please share the issue details you'd like me to convert into a GitHub issue title
Cue I could build it in a weekend vibes, I built my own agent TUI using the OpenAI agent SDK and Ink. Of course it’s not as fleshed out as Claude, but it supports git work trees for multi agent, slash commands, human in the loop prompts and etc. If I point it at the Anthropic models it more or less produces results as m good as the real Claude TUI.
I actually “decompiled” the Claude tools and prompts and recreated them. As of 6 months ago Claude was 15 tools, mostly pretty basic (list for, read file, wrote file, bash, etc) with some very clever prompts, especially the task tool it uses to do the quasi planning mode task bullets (even when not in planning mode).
Honestly the idea of bringing this all together with an affordable monthly service and obviously some seriously creative “prompt engineers” is the magic/hard part (and making the model itself, obviously).
If that’s the most complex TUI (yeah, new acronym) you’ve seen, you have a lot to catch up on!
I am talking rendering image/video in the terminal!
It is not at all a small app, at least as far as UX surface area. There are, what, 40ish slash commands? Each one is an opportunity for bugs and feature gaps.
The complex and magic parts are around finding contextual things to include, and I'd be curious how many are that vs "forgot to call clear() in the TUI framework before redirecting to another page".
I am not protecting anthropic[0], but how come in this forum every day I still see these "it's simple" takes from experienced people - I have no idea. There are who knows how many terminal emulators out there, with who knows how many different configurations. There are plugins for VSCode and various other editors (so it's not only TUI).
Looking at issue tracker ~1/3 of issues are seemingly feature requests[1].
Do not forget we are dealing with LLMs and it's a tool, which purpose and selling point that it codes on ANY computer in ANY language for ANY system. It's very popular tool run each day by who knows how many people - I could easily see, how such "relatively simple" tool would rack up thousands of issues, because "CC won't do weird thing X, for programming language Y, while I run from my terminal Z". And because it's LLM - theres whole can of non deterministic worms.
Have you created an LLM agent, especially with moderately complex tool usage? If yes and it worked flawlessly - tell your secrets (and get hired by Anthropic/ChatGPT/etc). Probably 80% of my evergrowing code was trying to just deal with unknown unknowns - what if LLM invokes tool wrong? How to guide LLM back on track? How to protect ourselves and keep LLM on track if prompts are getting out of hand or user tries to do something weird? The problems were endless...
Yes the core is "simple", but it's extremely deep can of worms, for such successful tool - I easily could see how there are many issues.
Also super funny, that first issue for me at the moment is how user cannot paste images when it has Korean language input (also issue description is in Korean) and second issue is about input problems in Windows Powershell and CMD, which is obviously total different world compared to POSIX (???) terminal emulators.
[0] I have very adverse feelings for mega ultra wealthy VC moneys...
[1] https://github.com/anthropics/claude-code/issues?q=is%3Aissu...
Its the best way to find out if there's a mismatch between value and effort, and its the best way to learn and discuss the fundamental nature of complexity.
Similar to your argument, I can name countless of situations where developers absolutely adamantly insisted that something was very hard to do, only for another developer to say "no you can actually do that like this* and fix it in hours instead of weeks.
Yes, making a TUI from scratch is hard, no that should not affect Claude code because they aren't actually making the TUI library (I hope). It should be the case that most complexity is in the model, and the client is just using a text-based interface.
There seems to be a mismatch of what you're describing would be issues (for instance about the quality of the agent) and what people are describing as the actual issues (terminal commands don't work, or input is lost arbitrarily).
That's why verbalizing is important, because you are thinking about other complexities than the people you reply to.
> There seems to be a mismatch of what you're describing would be issues (for instance about the quality of the agent) and what people are describing as the actual issues (terminal commands don't work, or input is lost arbitrarily).
I just named couple examples I've seen in issue tracker and `opencode` on quick skim has many similar issues about inputs and rendering issues in terminals too.
> Similar to your argument, I can name countless of situations where developers absolutely adamantly insisted that something was very hard to do, only for another developer to say "no you can actually do that like this* and fix it in hours instead of weeks.
Good example, as I have seen this too, but for this case, let's first see `opencode`/`claude` equivalent written in "two weeks" and that has no issues (or issues are fixed so fast, they don't accumulate into thousands) and supports any user on any platform. People building stuff for only themselves (N=1) and claiming the problem is simple do not count.
---------
Like the guy two days ago claiming that "the most basic feature"[1] in an IDE is a _terminal_. But then we see threads in HN popping up about Ghostty or Kitty or whatever and how those terminals are god-send, everything else is crap. They may be right, but that software took years (and probably tens of man-years) to write.
What I am saying is that just throwing out phrases that something is "simple" or "basic" needs proof, but at the time of writing I don't see examples.
This is indeed a nonsensical timeframe.
> What I am saying is that just throwing out phrases that something is "simple" or "basic" needs proof, but at the time of writing I don't see examples.
Fair point.
> This is indeed a nonsensical timeframe.
Sorry - I should have explained that it's an ironic hyperbole. Was thinking quotes will be enough, but Poe's law strikes again.
Tools like https://github.com/badlogic/pi-mono implement most of the functionality Claude Code has, even adding loads of stuff Claude doesn't have and can actually scroll without flickering inside terminal, all built by a single guy as a side project. I guess we can't ask that much from a 250B USD company.
Be careful with the coffee.
To me, their claim that they are vibe coding Claude code isn’t the flex they think it is.
I find it harder and harder to trust anthropic for business related use and not just hobby tinkering. Between buggy releases, opaque and often seemingly glitches rate limits and usage limits, and the model quality inconsistency, it’s just not something I’d want to bet a business on.
Unlike what another commenter suggested, this is a complex tool. I'm curious whether the codebase might eventually reach a point where it becomes unfixable; even with human assistance. That would be an interesting development. We'll see.
i wonder how many are real and not duplicates. i doubt github is well setup to handle said volume
Codex (by openai ironically) seems to be the fastest/most-responsive, opens instantly and is written in rust but doesn't contain that many features
Claude opens in around 3-4 seconds
Opencode opens in 2 seconds
Gemini-cli is an abomination which opens in around 16 second for me right now, and in 8 seconds on a fresh install
Codex takes 50ms for reference...
--
If their models are so good, why are they not rewriting their own react in cli bs to c++ or rust for 100x performance improvement (not kidding, it really is that much)
Some developers say 3-4 seconds are important to them, others don't. Who decides what the truth is? A human? ClawdBot?
Wasnt GTA 5 famous for very long start up time and turns out there some bug which some random developer/gamer found out and gave them a fix?
Most Gamers didnt care, they still played it.
[0] Perhaps everyone who actually takes pride in their craft and doesn’t prioritise shitty hustle culture and making money over everything else.
The Claude Code TUI itself is a front end, and should not be taking 3-4 seconds to load. That kind of loading time is around what VSCode takes on my machine, and VSCode is a full blown editor.
When all your other tools are fast and well engineered, slow and bloated is very noticeable.
If you build React in C++ and Rust, even if the framework is there, you'll likely need to write your components in C++/Rust. That is a difficult problem. There are actually libraries out there that allow you to build web UI with Rust, although they are for web (+ HTML/CSS) and not specifically CLI stuff.
So someone needs to create such a library that is properly maintained and such. And you'll likely develop slower in Rust compared to JS.
These companies don't see a point in doing that. So they just use whatever already exists.
- https://github.com/ratatui/ratatui
That's not a criticism of these frameworks -- there are constraints coming from Rust and from the scope of the frameworks. They just can't offer a React like experience.
But I am sure that companies like Anthropic or OpenAI aren't going to build their application using these libraries, even with AI.
Most modern UI systems are inspired by React or a variant of its model.
Opencode's core is actually written in zig, only ui orchestration is in solidjs. It's only slightly slower to load than neo-vim on my system.
Do you have a proof that gpt-5.2 or 5.3 codex takes 2 hours for the same problem that sonnet/opus4.5/4.6 take 5 minutes to solve? (I use both anthropic and openai models daily almost equally, and i'm not relating to what you said)
Sure codex-cli lacks way-too many features compared to claude-code (I use opencode), but your statement implies that openai models are absolute garbage (2h vs 5m to solve a problem)
React itself is a frontend-agnostic library. People primarily use it for writing websites but web support is actually a layer on top of base react and can be swapped out for whatever.
So they’re really just using react as a way to organize their terminal UI into components. For the same reason it’s handy to organize web ui into components.
I've used it myself. It has some rough edges in terms of rendering performance but it's nice overall.
But there are many different rendering libraries you can use with React, including Ink, which is designed for building CLI TUIs..
I thought this was a solid take
React fixes issues with the DOM being too slow to fully re-render the entire webpage every time a piece of state changes. That doesn't apply in a TUI, you can re-render TUIs faster than the monitor can refresh. There's no need to selectively re-render parts of the UI, you can just re-render the entire thing every time something changes without even stressing out the CPU.
It brings in a bunch of complexity that doesn't solve any real issues beyond the devs being more familiar with React than a TUI library.
300MB of RAM for a CLI app that reads files and makes HTTP calls is crazy. A new emacs GUI instance is like 70MB and that’s for an entire text editor with a GUI.
Diffing and only updating the parts of the TUI which have changed does make sense if you consider the alternative is to rewrite the entire screen every "frame". There are other ways to abstract this, e.g. a library like tqmd for python may well have a significantly more simple abstraction than a tree for storing what it's going to update next for the progress bar widget than claude, but it also provides a much more simple interface.
To me it seems more fair game to attack it for being written in JS than for using a particular "rendering" technique to minimise updates sent to the terminal.
The terminal does not have a render phase (or an update state phase). You either refresh the whole screen (flickering) or control where to update manually (custom engine, may flicker locally). But any updates are sequential (moving the cursor and then sending what to be displayed), not at once like 2D pixel rendering does.
So most TUI only updates when there’s an event to do so or at a frequency much lower than 60fps. This is why top and htop have a setting for that. And why other TUI software propose a keybind to refresh and reset their rendering engines.
What's apparently happening is that React tells Ink to update (re-render) the UI "scene graph", and Ink then generates a new full-screen image of how the terminal should look, then passes this screen image to another library, log-update, to draw to the terminal. log-update draws these screen images by a flicker-inducing clear-then-redraw, which it has now fixed by using escape codes to have the terminal buffer and combine these clear-then-redraw commands, thereby hiding the clear.
An alternative solution, rather than using the flicker-inducing clear-then-redraw in the first place, would have been just to do terminal screen image diffs and draw the changes (which is something I did back in the day for fun, sending full-screen ASCII digital clock diffs over a slow 9600baud serial link to a real terminal).
I'm not sure what the history of log-output has been or why it does the clear-before-draw. Another simple alternative to pre-clear would have been just to clear to end of line (ESC[0K) after each partial line drawn.
It’s not obvious to me that there’d be any benefit of using TypeScript and React instead, especially none that makes up for the huge downsides compared to Rust in a terminal environment.
Seems to me the problem is more likely the skills of the engineers, not Claude’s capabilities.
Who cares, and why?
All of the major providers' CLI harnesses use Ink: https://github.com/vadimdemedes/ink
Memory comparison of AI coding CLIs (single session, idle):
| Tool | Footprint | Peak | Language |
|-------------|-----------|--------|---------------|
| Codex | 15 MB | 15 MB | Rust |
| OpenCode | 130 MB | 130 MB | Go |
| Claude Code | 360 MB | 746 MB | Node.js/React |
vmmap shows Claude Code reserves 32.8 GB virtual memory just for the V8 heap, has 45% malloc fragmentation, and a peak footprint of 746 MB that never gets released, classic leak pattern.
On my 16 GB Mac, a "normal" workload (2 Claude sessions + browser + terminal) pushes me into 9.5 GB swap within hours. My laptop genuinely runs slower with Claude Code than when I'm running local LLMs.
I get that shipping fast matters, but building a CLI with React and a full Node.js runtime is an architectural choice with consequences. Codex proves this can be done in 15 MB. Every Claude Code session costs me 360+ MB, and with MCP servers spawning per session, it multiplies fast.
This is just regular tech debt that happens from building something to $1bn in revenue as fast as you possibly can, optimize later.
They're optimizing now. I'm sure they'll have it under control in no time.
CC is an incredible product (so is codex but I use CC more). Yes, lately it's gotten bloated, but the value it provides makes it bearable until they fix it in short time.
they're also total garbage
The amount of non-critical bugs all over the place is at least a magnitude larger than of any software I was using daily ever.
Plenty of built in /commands don't work. Sometimes it accepts keystrokes with 1 second delays. It often scrolls hundreds of lines in console after each key stroke Every now and then it crashes completely and is unrecoverable (I once have up and installed a fresh wls) When you ask it question in plan mode it is somewhat of an art to find the answer because after answering the question it will dump the whole current plan (free screens of text)
And just in general the technical feeling of the TUI is that of a vibe coded project that got too big to control.
Discussions are pointless when the parties are talking past each other.
file explorer takes 5 seconds to open
I've tried them all and I keep coming back to Claude Code because it's just so much more capable and useful than the others.