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OpenAI Codex base_instructions, for GPT-5.5

# 28th April 2026, 10:02 pm / openai, ai, llms, system-prompts, prompt-engineering, codex-cli, generative-ai, gpt

Five months in, I think I've decided that I don't want to vibecode — I want professionally managed software companies to use AI coding assistance to make more/better/cheaper software products that they sell to me for money.

Matthew Yglesias

# 28th April 2026, 1:25 pm / agentic-engineering, vibe-coding, ai-assisted-programming, ai

Since GPT-5.4, we’ve unified Codex and the main model into a single system, so there’s no separate coding line anymore.

GPT-5.5 takes this further, with strong gains in agentic coding, computer use, and any task on a computer.

Romain Huet, confirming OpenAI won't release a GPT-5.5-Codex model

# 25th April 2026, 12:06 pm / generative-ai, gpt, openai, ai, llms

[...] if you ever needed another reason to learn in public by digital gardening or podcasting or streaming or whathaveyou, add on that people will assume you’re more competent than you are. This will get you invites to very cool exclusive events filled with high-achieving, interesting people, even though you have no right to be there. A+ side benefit.

Maggie Appleton, Gathering Structures (via)

# 23rd April 2026, 1:35 pm / blogging, maggie-appleton

As part of our continued collaboration with Anthropic, we had the opportunity to apply an early version of Claude Mythos Preview to Firefox. This week’s release of Firefox 150 includes fixes for 271 vulnerabilities identified during this initial evaluation. [...]

Our experience is a hopeful one for teams who shake off the vertigo and get to work. You may need to reprioritize everything else to bring relentless and single-minded focus to the task, but there is light at the end of the tunnel. We are extremely proud of how our team rose to meet this challenge, and others will too. Our work isn’t finished, but we’ve turned the corner and can glimpse a future much better than just keeping up. Defenders finally have a chance to win, decisively.

Bobby Holley, CTO, Firefox

# 22nd April 2026, 5:40 am / anthropic, claude, ai, firefox, llms, mozilla, security, generative-ai, ai-security-research

AI agents are already too human. Not in the romantic sense, not because they love or fear or dream, but in the more banal and frustrating one. The current implementations keep showing their human origin again and again: lack of stringency, lack of patience, lack of focus. Faced with an awkward task, they drift towards the familiar. Faced with hard constraints, they start negotiating with reality.

Andreas Påhlsson-Notini, Less human AI agents, please.

# 21st April 2026, 4:39 pm / ai-agents, coding-agents, ai

The real goldmine isn’t that Apple gets a cut of every App Store transaction. It’s that Apple’s platforms have the best apps, and users who are drawn to the best apps are thus drawn to the iPhone, Mac, and iPad. That edge is waning. Not because software on other platforms is getting better, but because third-party software on iPhone, Mac, and iPad is regressing to the mean, to some extent, because fewer developers feel motivated — artistically, financially, or both — to create well-crafted idiomatic native apps exclusively for Apple’s platforms.

John Gruber

# 15th April 2026, 5:13 pm / apple, john-gruber

I think we will see some people employed (though perhaps not explicitly) as meat shields: people who are accountable for ML systems under their supervision. The accountability may be purely internal, as when Meta hires human beings to review the decisions of automated moderation systems. It may be external, as when lawyers are penalized for submitting LLM lies to the court. It may involve formalized responsibility, like a Data Protection Officer. It may be convenient for a company to have third-party subcontractors, like Buscaglia, who can be thrown under the bus when the system as a whole misbehaves.

Kyle Kingsbury, The Future of Everything is Lies, I Guess: New Jobs

# 15th April 2026, 3:36 pm / ai-ethics, careers, ai, kyle-kingsbury

The problem is that LLMs inherently lack the virtue of laziness. Work costs nothing to an LLM. LLMs do not feel a need to optimize for their own (or anyone's) future time, and will happily dump more and more onto a layercake of garbage. Left unchecked, LLMs will make systems larger, not better — appealing to perverse vanity metrics, perhaps, but at the cost of everything that matters.

As such, LLMs highlight how essential our human laziness is: our finite time forces us to develop crisp abstractions in part because we don't want to waste our (human!) time on the consequences of clunky ones.

Bryan Cantrill, The peril of laziness lost

# 13th April 2026, 2:44 am / bryan-cantrill, ai, llms, ai-assisted-programming, generative-ai

I have a feeling that everyone likes using AI tools to try doing someone else’s profession. They’re much less keen when someone else uses it for their profession.

Giles Turnbull, AI and the human voice

# 8th April 2026, 3:18 pm / ai-ethics, writing, ai

From anonymized U.S. ChatGPT data, we are seeing:

  • ~2M weekly messages on health insurance
  • ~600K weekly messages [classified as healthcare] from people living in “hospital deserts” (30 min drive to nearest hospital)
  • 7 out of 10 msgs happen outside clinic hours

Chengpeng Mou, Head of Business Finance, OpenAI

# 5th April 2026, 9:47 pm / ai-ethics, generative-ai, openai, chatgpt, ai, llms

[GitHub] platform activity is surging. There were 1 billion commits in 2025. Now, it's 275 million per week, on pace for 14 billion this year if growth remains linear (spoiler: it won't.)

GitHub Actions has grown from 500M minutes/week in 2023 to 1B minutes/week in 2025, and now 2.1B minutes so far this week.

Kyle Daigle, COO, GitHub

# 4th April 2026, 2:20 am / github, github-actions

On the kernel security list we've seen a huge bump of reports. We were between 2 and 3 per week maybe two years ago, then reached probably 10 a week over the last year with the only difference being only AI slop, and now since the beginning of the year we're around 5-10 per day depending on the days (fridays and tuesdays seem the worst). Now most of these reports are correct, to the point that we had to bring in more maintainers to help us.

And we're now seeing on a daily basis something that never happened before: duplicate reports, or the same bug found by two different people using (possibly slightly) different tools.

Willy Tarreau, Lead Software Developer. HAPROXY

# 3rd April 2026, 9:48 pm / security, linux, generative-ai, ai, llms, ai-security-research

The challenge with AI in open source security has transitioned from an AI slop tsunami into more of a ... plain security report tsunami. Less slop but lots of reports. Many of them really good.

I'm spending hours per day on this now. It's intense.

Daniel Stenberg, lead developer of cURL

# 3rd April 2026, 9:46 pm / daniel-stenberg, security, curl, generative-ai, ai, llms, ai-security-research

Months ago, we were getting what we called 'AI slop,' AI-generated security reports that were obviously wrong or low quality. It was kind of funny. It didn't really worry us.

Something happened a month ago, and the world switched. Now we have real reports. All open source projects have real reports that are made with AI, but they're good, and they're real.

Greg Kroah-Hartman, Linux kernel maintainer (bio), in conversation with Steven J. Vaughan-Nichols

# 3rd April 2026, 9:44 pm / security, linux, generative-ai, ai, llms, ai-security-research

I want to argue that AI models will write good code because of economic incentives. Good code is cheaper to generate and maintain. Competition is high between the AI models right now, and the ones that win will help developers ship reliable features fastest, which requires simple, maintainable code. Good code will prevail, not only because we want it to (though we do!), but because economic forces demand it. Markets will not reward slop in coding, in the long-term.

Soohoon Choi, Slop Is Not Necessarily The Future

# 1st April 2026, 2:07 am / slop, ai-assisted-programming, generative-ai, agentic-engineering, ai, llms

Note that the main issues that people currently unknowingly face with local models mostly revolve around the harness and some intricacies around model chat templates and prompt construction. Sometimes there are even pure inference bugs. From typing the task in the client to the actual result, there is a long chain of components that atm are not only fragile - are also developed by different parties. So it's difficult to consolidate the entire stack and you have to keep in mind that what you are currently observing is with very high probability still broken in some subtle way along that chain.

Georgi Gerganov, explaining why it's hard to find local models that work well with coding agents

# 30th March 2026, 9:31 pm / coding-agents, generative-ai, ai, local-llms, llms, georgi-gerganov

The thing about agentic coding is that agents grind problems into dust. Give an agent a problem and a while loop and - long term - it’ll solve that problem even if it means burning a trillion tokens and re-writing down to the silicon. [...]

But we want AI agents to solve coding problems quickly and in a way that is maintainable and adaptive and composable (benefiting from improvements elsewhere), and where every addition makes the whole stack better.

So at the bottom is really great libraries that encapsulate hard problems, with great interfaces that make the “right” way the easy way for developers building apps with them. Architecture!

While I’m vibing (I call it vibing now, not coding and not vibe coding) while I’m vibing, I am looking at lines of code less than ever before, and thinking about architecture more than ever before.

Matt Webb, An appreciation for (technical) architecture

# 28th March 2026, 12:04 pm / matt-webb, ai, llms, vibe-coding, coding-agents, ai-assisted-programming, generative-ai, agentic-engineering, definitions

FWIW, IANDBL, TINLA, etc., I don’t currently see any basis for concluding that chardet 7.0.0 is required to be released under the LGPL. AFAIK no one including Mark Pilgrim has identified persistence of copyrightable expressive material from earlier versions in 7.0.0 nor has anyone articulated some viable alternate theory of license violation. [...]

Richard Fontana, LGPLv3 co-author, weighing in on the chardet relicensing situation

# 27th March 2026, 9:11 pm / open-source, ai-ethics, llms, ai, generative-ai, ai-assisted-programming

I really think "give AI total control of my computer and therefore my entire life" is going to look so foolish in retrospect that everyone who went for this is going to look as dumb as Jimmy Fallon holding up a picture of his Bored Ape

Christopher Mims, Technology columnist at The Wall Street Journal

# 24th March 2026, 8:35 pm / ai, security

slop is something that takes more human effort to consume than it took to produce. When my coworker sends me raw Gemini output he’s not expressing his freedom to create, he’s disrespecting the value of my time

Neurotica, @schwarzgerat.bsky.social

# 23rd March 2026, 11:31 pm / ai-ethics, slop, generative-ai, ai, llms

I have been doing this for years, and the hardest parts of the job were never about typing out code. I have always struggled most with understanding systems, debugging things that made no sense, designing architectures that wouldn't collapse under heavy load, and making decisions that would save months of pain later.

None of these problems can be solved LLMs. They can suggest code, help with boilerplate, sometimes can act as a sounding board. But they don't understand the system, they don't carry context in their "minds", and they certianly don't know why a decision is right or wrong.

And the most importantly, they don't choose. That part is still yours. The real work of software development, the part that makes someone valuable, is knowing what should exist in the first place, and why.

David Abram, The machine didn't take your craft. You gave it up.

# 23rd March 2026, 6:56 pm / careers, ai-assisted-programming, generative-ai, ai, llms

Congrats to the @cursor_ai team on the launch of Composer 2!

We are proud to see Kimi-k2.5 provide the foundation. Seeing our model integrated effectively through Cursor's continued pretraining & high-compute RL training is the open model ecosystem we love to support.

Note: Cursor accesses Kimi-k2.5 via @FireworksAI_HQ hosted RL and inference platform as part of an authorized commercial partnership.

Kimi.ai @Kimi_Moonshot, responding to reports that Composer 2 was built on top of Kimi K2.5

# 20th March 2026, 8:29 pm / kimi, generative-ai, ai, cursor, llms, ai-in-china

Great news—we’ve hit our (very modest) performance goals for the CPython JIT over a year early for macOS AArch64, and a few months early for x86_64 Linux. The 3.15 alpha JIT is about 11-12% faster on macOS AArch64 than the tail calling interpreter, and 5-6%faster than the standard interpreter on x86_64 Linux.

Ken Jin, Python 3.15’s JIT is now back on track

# 17th March 2026, 9:48 pm / python

If you do not understand the ticket, if you do not understand the solution, or if you do not understand the feedback on your PR, then your use of LLM is hurting Django as a whole. [...]

For a reviewer, it’s demoralizing to communicate with a facade of a human.

This is because contributing to open source, especially Django, is a communal endeavor. Removing your humanity from that experience makes that endeavor more difficult. If you use an LLM to contribute to Django, it needs to be as a complementary tool, not as your vehicle.

Tim Schilling, Give Django your time and money, not your tokens

# 17th March 2026, 4:13 pm / ai-ethics, open-source, generative-ai, ai, django, llms

The point of the blackmail exercise was to have something to describe to policymakers—results that are visceral enough to land with people, and make misalignment risk actually salient in practice for people who had never thought about it before.

A member of Anthropic’s alignment-science team, as told to Gideon Lewis-Kraus

# 16th March 2026, 9:38 pm / ai-ethics, anthropic, claude, generative-ai, ai, llms

Tidbit: the software-based camera indicator light in the MacBook Neo runs in the secure exclave¹ part of the chip, so it is almost as secure as the hardware indicator light. What that means in practice is that even a kernel-level exploit would not be able to turn on the camera without the light appearing on screen. It runs in a privileged environment separate from the kernel and blits the light directly onto the screen hardware.

Guilherme Rambo, in a text message to John Gruber

# 16th March 2026, 8:34 pm / hardware, apple, privacy, john-gruber

GitHub’s slopocalypse – the flood of AI-generated spam PRs and issues – has made Jazzband’s model of open membership and shared push access untenable.

Jazzband was designed for a world where the worst case was someone accidentally merging the wrong PR. In a world where only 1 in 10 AI-generated PRs meets project standards, where curl had to shut down its bug bounty because confirmation rates dropped below 5%, and where GitHub’s own response was a kill switch to disable pull requests entirely – an organization that gives push access to everyone who joins simply can’t operate safely anymore.

Jannis Leidel, Sunsetting Jazzband

# 14th March 2026, 6:41 pm / ai-ethics, open-source, python, ai, github

Simply put: It’s a big mess, and no off-the-shelf accounting software does what I need. So after years of pain, I finally sat down last week and started to build my own. It took me about five days. I am now using the best piece of accounting software I’ve ever used. It’s blazing fast. Entirely local. Handles multiple currencies and pulls daily (historical) conversion rates. It’s able to ingest any CSV I throw at it and represent it in my dashboard as needed. It knows US and Japan tax requirements, and formats my expenses and medical bills appropriately for my accountants. I feed it past returns to learn from. I dump 1099s and K1s and PDFs from hospitals into it, and it categorizes and organizes and packages them all as needed. It reconciles international wire transfers, taking into account small variations in FX rates and time for the transfers to complete. It learns as I categorize expenses and categorizes automatically going forward. It’s easy to do spot checks on data. If I find an anomaly, I can talk directly to Claude and have us brainstorm a batched solution, often saving me from having to manually modify hundreds of entries. And often resulting in a new, small, feature tweak. The software feels organic and pliable in a form perfectly shaped to my hand, able to conform to any hunk of data I throw at it. It feels like bushwhacking with a lightsaber.

Craig Mod, Software Bonkers

# 13th March 2026, 5:14 pm / vibe-coding, ai-assisted-programming, generative-ai, ai, llms

Here's what I think is happening: AI-assisted coding is exposing a divide among developers that was always there but maybe less visible.

Before AI, both camps were doing the same thing every day. Writing code by hand. Using the same editors, the same languages, the same pull request workflows. The craft-lovers and the make-it-go people sat next to each other, shipped the same products, looked indistinguishable. The motivation behind the work was invisible because the process was identical.

Now there's a fork in the road. You can let the machine write the code and focus on directing what gets built, or you can insist on hand-crafting it. And suddenly the reason you got into this in the first place becomes visible, because the two camps are making different choices at that fork.

Les Orchard, Grief and the AI Split

# 12th March 2026, 4:28 pm / les-orchard, ai-assisted-programming, generative-ai, ai, llms, careers, deep-blue