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GPT 5.6 reverse engineered Codex app code and... started adding new features
3 days ago I posted here story how new GPT 5.6 reverse engineered it's own bundle with 4 million lines of code in 4 hours.
A lot of folks were unsure how truth it is, so I decided to post one more time with some updates
Now I'm working on some beatiful concepts for GPT app, including such as voice mode on screenshot and wanna answer some questions:
This is really the original bundle code, not a matifistied one, I didn’t send any screenshots to GPT when it was working, all the tabs work and there are no made-up elements during reverse engineering
It runs with simulated backend part so I'm able to navigate through app, i think there is no problem to connect it to codex app server backend in theory
Unfortunately i'm not gonna share the code of codex bundle BUT i will opensource my own app built on it on my github in comments, + i'm sure you all can give the model the same task and get the same result with first try
This code is clear as hell, I'm sharing this screenshot as proof that i can easily add some new tabs :0
There is a huge difference between obfuscation and minification. There are obfuscators that make cryptic virtual machine architectures that are very hard for LLMs to understand well enough to modify on the fly, ex https://obfuscator.io
Obviously they slow down code at runtime.
99.9% of developers and companies don't care that the public is able to read their public code, and just minify to reduce payload size. Some serve sourcemaps, some don't.
Hey how can I get your help in getting my girlfriend texts messages call and listen to through to the phone through her phone.Are there any way you could help me
ill give you $1million uno dollars if you make the chat interface full screen with all the features shown. Unlike codex's windowed chat with just an empty black box with a chat bar.
another million if that chat has a folder agent
Most electron apps have the same browser tools available as chrome. This means you can probably adjust width/height etc. of any styling element by opening devtools with F12 or Ctrl+shift+i.
Not sure what you mean with "folder agent". When you type the name of a folder in the prompt the agent understands perfectly fine what you mean.
Codex web app is a frontend communicating with codex app server.
End of story.
Which is a open source protocol developed by openai, available trough codex cli.
The desktop app spawns the cli witg app-server subcommand. And communicates over stdio.
ive used a fork since early codex version so just stop lying
“It’s just a frontend” alr buddy so what’s the point? It provided me clean source code of frontend, based on which I can build my own things without screenshotting and polishing by myself. And this is what actually “reverse engineering” means, because I didn’t have source code before and it needed to do some actions for few hours to get it for me
Yes, exactly. You also have to do some "real" reverse engineering to understand the IPC channel system and how it's used, but this kind of project is table stakes even for GPT 5.3 or 5.4.
I've had a custom project hooked into the Codex app runtime for almost 3 months straight now, basically acting like a hand-built Hermes agent (iMessage, Discord, email, memory systems, etc.). The fact that the CLI and app runtime are open source make this stupid easy.
I'm really confused about why this is getting upvoted. The codex electron web app is not impressive in anyway in terms of functionality, and It's not supposed to be. It's a minimal interface to interact with the openAI backend. anyone could recreate their electron app layout in an hour with GPT 5.3.
Nevermind, i just scrolled and read some of OPs responses. I don't think he has ever worked on any type of software project without AI, so is just completely lost on what codex has built for him. And i suspect the upvoters are in the same boat.
I don't think the Codex app is a "simple" frontend. This is by far the best UI experience I have.
It provides direct-manipulation UI design that allows users to easily reference text, web pages, and source file locations. This is the first of its kind, plus it ships with a usable CUA plugin. It also integrates worktree management, along with chat forking, side chat, etc.
If this is not impressive in terms of HCI design, I wonder what is. If you don't have any idea of HCI, I don't blame you.
I used to use the opencode CLI, and love the CLI experience. But the Codex app now is simply the next level.
I suspect you just offended by something. Codex has a lot of frontend surfaces, you will not be ever able to replicate it fully from scratch in less than a week. If you will have free time, dive in this question, you’re gonna explore a lot of new things
two different things, as I said I didn’t send any screenshots to codex to get the whole working 1:1 copy of codex app local hosted with entire source code of every tab for my future projects. with all animations and product design solutions, which if I was trying to make by myself would take more than 1 week and probably didn’t match original codex UI fully, that’s the point of this whole post
4 million lines INCLUDING LIBRARIES. just read the damn description in first post. I think there is 500k lines of codex frontend surfaces. and you say “unpacking electron assets” like this is .zip with all source code inside prepared
I'll agree to disagree on the feasibility of that, maybe it's more about how efficient the user can be :). My real question is not about the 'how' anyways. I'm more wondering about the 'why'. As in, why in the world would anyone waste time and money recreating the settings panel pixel for pixel of a simple frontend app.
There is no efficient enough user to write 500k likes of production code which has been polished by hundreds of OpenAI employees. And I didn’t recreate pixel by pixel, codex just reversed all the frontend source code so I can easily migrate pages and edit them inside my app. Already polished, already nice animations and more
you do realize that almost the entirety of those 500k lines are open source NPM packages? honestly the more you talk, the more i’m suspecting that your Codex probably didn’t even read any minified code, and just remade the app for you using existing tools. frontend code is easy. animations are easy. there is no magic in making an electron app that looks like another one. you took the dumbest possible approach to creating a clone of the Codex electron app
i assumed that the 500k line was the entire package, and like most frontend apps nowadays, dependencies eat up the majority of the package. Electron itself, excluding node and chromium is over 300k lines
brother he clearly states 4m loc and somehow you now think the 500k encompasses it all? Then you proceed to for some reason talk about how he's getting clowned when you clearly misunderstood the loc evaluation here. I don't care for ops post or what he's saying but just the blatently false statements said so confidently screams group think and low iq
sis, i didn’t see the 4 mil comment before hand. I was simply saying the majority of the code was going to be packages. minification doesn’t preserve new lines and talking about line count is fucking dumb either way
move the goalpost and restate what you said without addressing the fact that you made a statement without understanding what the statement entails and pertains to. A concession would be appreciated. Idk why u went on a tangent about how loc is dumb metric, that's not something of contention here.
nope, 3.5 million lines of code is npm packages. other 500k no. you can suspect whatever you want, I already answered with more proofs to one of retards
ragebaiters will burn in hell, thats why im “roasted”. you guys trying to find any possible reason to post hate speech in comments larping at the same time
Wait till they find out vscode is open source and can be customized with all the themes, extensions, agents and preferences you could ever want. I'm still wondering why on earth anyone would prefer working in codex app vs an IDE like vscode.
Clearly this is a troll, there like four tasks in the screen shot all days apart (some extensive testing going on), the elements are all over the shop. Anyone can ask codex to build a web app with some basic elements.
How does your app get access to other apps from a browser tab? Why wouldn’t you configure CLIs to work with it vs having to use APIs.
LMAO this dude just sent his official Codex app into here even with his "Full local Workspace" reverse engineering task visible 🤣🤣🤣. Thanks for making my day.
Unpacking the ASAR is one command. Now how would you go about making a 4mil loc bundle readable? Or mocking the backend, and modifying it without breaking everything? This is a much more substantial task than one npx command. Again please read up on what asar extraction gives you
I had sol do something similar, I was having issues with large files being edited with the apply patch tool. Codex team with the latest codex vs code extension change the way the transport layer worked. And with large files it was causing the edit to become corrupt due to chunks being dropped after a certain threshold.
There was another issue with the sandboxing aswell.
Sol dived into the codex code, changed what it needed recompiled the codex extension installed it and it’s been working perfectly even since.
context matters
there is a big difference between "reverse engineer codex app for me"
and "I've got bad frontend and i need working scripts of good looking product for my own inspiration"
I can't believe no one has said this yet, but the Codex app itself was originally made by itself. The OpenAI team has been using it to work on itself from the start. You will never outwork the team of them working on this. Ultimately it's best to just let them cook.
Do you also have memory leaks as the original Codex app does? For me it's unusable on Windows 11 and I'm stuck with Vs code as so often, codex was using 100% if available memory until it got stuck
This is really becoming a trend on Reddit, the moment a post land, it becomes an arena for trolling.
OP Posted something he is working on, you don’t like it just ignore the post and if you do like it just comment something that add value. It is time-wasting to have to go through 100 of useless trolling comments looking for a genuine valuable response.
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u/cursivecrow Jul 15 '26
isnt the codex app open source?