Boris Cherny

“Every six months, delete your Cloud MD. Delete your skills. Delete your hooks. See what the model does, and it might surprise you. And actually for Opus Five, this is something we really do recommend, is just try deleting all of these things, because the model…”

“The thing that you want to do is you want to run it. And if it's like a custom agentic product that you're building, you want to kind of run the products. You want to see where it fails with the model. You want to see what it does well. If you're using quad co…”

“And for modern models, that's actually really not the way to do it. You want to go a little bit higher level. You want to describe the task. You want to describe the guardrails. You want to describe, like, the exit criteria, and then just go with the model coo…”

“One example is the model can now rewrite essentially any code base from one language to a different language.”

“When I look at engineers that have been, you know, coding for a long time, you know, like for years or for decades, this is a really, really common failure mode is trying to over specify and it's trying to be overly specific and then, you know, get the model t…”

“The thing that made quad code different from chatbots at the time was quad code can use tools. And this is it. Like, this is just the difference. It's, with a chatbot, you're going back and forth and you're talking, but an agent, and Cloud Code is an agent, it…”

“Even something as simple as like editing a file on your computer. You know, like a year and a half ago, there was no AI product that could actually do that. But this is the first thing that quad code was able to do. It could edit a file on your desktop.”

“Every month there's a step change in what it can do. And as a user of this technology, it's just quite hard because you have to kind of keep retraining. You have to keep retrying. You always need this like beginner mindset to retry the technology and use it fo…”

“I don't think token maxing is a large percent.”

“What happened with Claude is now many companies, including Anthropic, and all of our biggest customers are reporting gains on the order of hundreds of percentage points. And I think the last number that we reported is the amount of code written per engineer at…”

“The challenge is you can't identify these engineers and these people ahead of time. You don't know who they are. And it's almost always going to surprise you. And so the thing you want to do is let people experiment, give them safety, and then once there's som…”

“I think we should probably optimize for intelligence. That's the most important thing. So even if it's like a little bit less efficient, but it's more intelligent and it lets you do more things, that's really useful because the efficiency optimization comes af…”

“Nowadays, I'm running, you know, like, on my computer, I run maybe five at a time, and then every night, I run, like, you know, not every night, but most nights, I run, like, hundreds of quads at a time. Hundreds. Yeah, hundreds, sometimes thousands.”

“When you look at the kind of engineering that I do, I don't write code. I prompt quad. And actually nowadays, mostly what I'm doing is I have a Claude that prompts other Claude. So I don't even talk to Claude. I have a Claude that's talking to my Claude.”

“One that I think will increase in importance is something like network effects, because it doesn't matter who's writing the code. It doesn't matter if it's an agent at the core of your product or something else, or if there's intelligence in your product. If t…”

“Some modes get less important, and this is, for example, switching costs, because if you want to switch from vendor A to vendor B, you can, you know, you can just ask Quad to do that, and Quad is going to get better and better over time at it.”

“It's crazy, like, you teach this thing to predict the next word, and somehow, if the next word is hard enough, it has to learn to really plan ahead, and it has to learn how to do all of this.”

“There's one person that built and sold a startup as a result of one of these hackathons that we put on.”

“He's our tech lead. He's very much the product visionary. And he is great at setting like, this is what the product needs to be. In like three months, six months from now. This is like what the AGI-pilled version of the product is. And a lot of my role is figu…”

“So we actually think if you look at private repositories, it's quite a bit higher than that.”

“We were building the models in this way that kind of fit our mental model of the way that we built SafeHEI, where the model starts by being really good at coding, then it gets really good at tool use, then it gets really good at computer use. Roughly, this is …”

“And for me, this is actually a pretty important product lesson, right? It's like you want to under-resource things a little bit at the start.”

“Actually, something that people don't really remember is Cloud Code was not initially a hit. When we released it got a bunch of users. There was a lot of early adopters that got it immediately, but it actually took many months for everyone to really understand…”

“And my prediction back in May of 2025 was, by the end of the year, you might not need an IDE to code anymore, and we're gonna start to see engineers not doing this.”

“Because even in February when we released it was writing maybe, I don't know, like, 20% of my code, not more. And even in May, it was writing maybe 30%. I was still using, you know, Kurtzer for most of my code. And it only crossed a hundred percent in November…”

“Every, you know, every day I ship like 10, 20, 30 pull requests, something like that.”

“I have not edited a single line by hand since November.”

“All of my project management for the team co-work does all of it. It's like syncing stuff between spreadsheets and messaging people on Slack and email and all this kind of stuff.”

“And over the next few months, I think what we're going to see is just across the industry, it's going to become increasingly solved, you know, for every kind of code base, every tech stack that people work on.”

“There's this there's interesting thing that happens also when you when you underfund everything a little bit because then people are kind of forced to clodify.”

“My advice generally is don't try to optimize. Don't try to cost cut at the beginning. Start by just giving engineers as many tokens as possible.”

“You know, at Anthropic, we're starting to see some engineers that are spending, you know, like hundreds of thousands a month in, in tokens.”

“My take is, I think for people that are using that are using quad code, that are using agents to code today, you still have to understand the layer under. But yeah, in a year or two, it's not gonna matter.”

“I think it's going to be a lot of the roles that are adjacent to engineering. So yeah, it could be like product managers. It could be design, could be data science. It is going to expand to pretty much any kind of work that you can do on a computer because the…”

“And so I imagine a world, you know, a few years in the future where everyone is able to program. And what does that unlock? Anyone can just build software anytime. And I have no idea. It's just the same way that, you know, in the 1400, no one could have predic…”

“So I think a lot of the people that will be rewarded the most over the next few years, they won't just be AI native and they don't just know how to use these tools really well, but also they're curious and they're generalists. And they cross over multiple disc…”

“Latent demand is this idea that if you build a product in a way that can be hacked or can be kind of misused by people in a way it wasn't really designed for to do kind of something that they want to do, then this helps you as the product builder learn where t…”

“I always have a bunch of agents running. So like at the moment I have like five agents running and at any moment, like, you know, like I wake up and I start a bunch of agents.”

“Maybe a third of my code now is in the terminal, but also a third is using the desktop app. And then a third is the iOS app, which is just so surprising because I did not think that this would be the way that I code in, even in twenty-twenty-six.”

“And in general, what we see is maybe scaffolding can improve performance, maybe 10, 20%, something like this. But often these gains just get wiped out with the next model. So it's almost better to just wait for the next one.”

“And Opus four was our first kind of ASL three class model that we released back in May. And we just saw this inflection because everyone started to use quad code for the first time. And that, that was kind of when our growth really went exponential. And like I…”

“And so I think over time, this is going to become more and more normal where the models are running for a very, very long period of time and you don't have to sit there and babysit them anymore.”

“Like if someone has a bug, like I can probably fix it within a few minutes. Cause I just sort of clawed and as long as the description is good, it will just go and do it.”

“Even in February when we GA'd it wrote maybe like 10% of my code or something like that. I didn't really use it to write code. It wasn't very good at it. I still wrote most of my code by hand.”

“Yes, because I didn't have to build a UI. So it was just me.”

“And I asked it, what music am I listening to? He wrote some, like, Apple script to script my Mac and look up the music in my music player. And this was sauna 3.5.”

“There's this other general principle that I think is maybe interesting where you can build for the model and then you can build scaffolding around the model in order to improve performance a little bit. And depending on the domain, you can improve performance,…”

“And really, I think that's why we stayed in the CLI is because we felt there is no UI we could build that would still be relevant in six months because the model was improving so quickly.”

“I remember early on, this is maybe six months ago, I tried to get rid of bash output, just internally, just to, like, summarize it, because I was like, these giant long bash commands, I don't actually care. And then I gave it to anthropic employees for a day, …”

“And quad code, like took the heap dump. It wrote a little tool for itself to like analyze the heap dump. And then it found the leak faster than I did.”

“In my old job at a big company, when I hired like architects and this kind of a type of engineer, you look for people that have a lot of experience and really strong opinions, but it actually turns out a lot of this stuff just isn't relevant anymore. And a lot…”

“When I look at engineers on the team that I think are the most effective, there's essentially two, it's very bimodal. There's one side where it's extreme specialists and so, like, I named Jared before, like, he's a really good example of this, and kind of the …”

“And nowadays what I find with Opus 4.5, I think it started with 4.6, it got really good. Once the plan is good, it just stays on track, and it'll just do the thing exactly right almost every time.”

“The way I would frame it is think about the thing that the model wants to do and figure out how do you make that easier? And that's something that we saw, you know, like when I first started hacking on Claude code, I realized like this thing just wants to use …”

“All of CloudCode has just been written and rewritten and rewritten and rewritten over and over and over. We unship tools every couple weeks. We add new tools every couple weeks. There's no part of CloudCode that was around six months ago. It's just constantly …”

“And since Quad Code came out, productivity per engineer at Anthropic has grown a 150%.”

“So one is it operates as a research lab. So the product org was teeny, teeny, tiny. It's really all about building a safe model. That's all that matters. And so this idea of just being very close to the model and being very close to development and being not t…”

“For me personally, it's been a hundred percent for like since Opus 4.5. I just, I uninstalled my IDE. I don't edit a single line of code by hand. It's just a hundred percent quad code in Opus. And you know, I land, you know, like 20 pairs a day, every day.”

“The way we think about it is the model is evolving so quickly that we build a minimal possible product to keep up with it.”

“Maybe coding is the way that we get to the next level of intelligence. If you call it like AGI or ASI or whatever, the model needs some way to interact with the world and for a model, the natural way is code.”