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How I Use Every Claude Code Feature

How I Use Every Claude Code Feature Useful, detailed guide from Shrivu Shankar, a Claude Code power user. Lots of tips for both individual Claude Code usage and configuring it for larger team projects. I appreciated Shrivu's take on MCP: The "Scripting" model (now formalize...

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October 2025 sponsors-only newsletter

I just hit send on the October edition of my sponsors-only monthly newsletter. If you are a sponsor (or if you start a sponsorship now) you can access a copy here. In the newsletter this month:

  • Coding agents and "vibe engineering"
  • Claude Code for web
  • NVIDIA DGX Spark
  • Claude Skills
  • OpenAI DevDay and GitHub Universe
  • Python 3.14
  • October in Chinese Al model releases
  • Miscellaneous extras
  • Tools I'm using at the moment

Here's a copy of the September newsletter as a preview of what you'll get. Pay $10/month to stay a month ahead of the free copy!

Tags: newsletter

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Claude Code Can Debug Low-level Cryptography

Claude Code Can Debug Low-level Cryptography Go cryptography author Filippo Valsorda reports on some very positive results applying Claude Code to the challenge of implementing novel cryptography algorithms. After Claude was able to resolve a "fairly complex low-level bug" i...

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Quoting Julian Andres Klode

I plan to introduce hard Rust dependencies and Rust code into APT, no earlier than May 2026. This extends at first to the Rust compiler and standard library, and the Sequoia ecosystem.

In particular, our code to parse .deb, .ar, .tar, and the HTTP signature verification code would strongly benefit from memory safe languages and a stronger approach to unit testing.

If you maintain a port without a working Rust toolchain, please ensure it has one within the next 6 months, or sunset the port.

Julian Andres Klode, debian-devel mailing list

Tags: open-source, debian, rust, linux

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CoreWeave adds Marimo to their 2025 acquisition spree

Marimo is Joining CoreWeave I don't usually cover startup acquisitions here, but this one feels relevant to several of my interests. Marimo (previously) provide an open source (Apache 2 licensed) notebook tool for Python, with first-class support for an additional WebAssembl...

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Curiosity-driven blogging

My piece this morning about the Marimo acquisition is an example of a variant of a TIL - I didn't know much about CoreWeave, the acquiring company, so I poked around to answer my own questions and then wrote up what I learned as a short post. Curiosity-driven blogging if you like.

Tags: til, blogging

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Marimo is Joining CoreWeave

Marimo is Joining CoreWeave I don't usually cover startup acquisitions here, but this one feels relevant to several of my interests. Marimo (previously) provide an open source (Apache 2 licensed) notebook tool for Python, with first-class support for an additional WebAssembl...

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Quoting François Chollet

To really understand a concept, you have to "invent" it yourself in some capacity. Understanding doesn't come from passive content consumption. It is always self-built. It is an active, high-agency, self-directed process of creating and debugging your own mental models.

François Chollet

Tags: francois-chollet, teaching

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Introducing SWE-1.5: Our Fast Agent Model

Introducing SWE-1.5: Our Fast Agent Model Here's the second fast coding model released by a coding agent IDE in the same day - the first was Composer-1 by Cursor. This time it's Windsurf releasing SWE-1.5: Today we’re releasing SWE-1.5, the latest in our family of models op...

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MiniMax M2 & Agent: Ingenious in Simplicity

MiniMax M2 & Agent: Ingenious in Simplicity MiniMax M2 was released on Monday 27th October by MiniMax, a Chinese AI lab founded in December 2021. It's a very promising model. Their self-reported benchmark scores show it as comparable to Claude Sonnet 4, and Artificial An...

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Composer: Building a fast frontier model with RL

Composer: Building a fast frontier model with RL Cursor released Cursor 2.0 today, with a refreshed UI focused on agentic coding (and running agents in parallel) and a new model that's unique to Cursor called Composer 1. As far as I can tell there's no way to call the m...

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Hacking the WiFi-enabled color screen GitHub Universe conference badge

I'm at GitHub Universe this week (thanks to a free ticket from Microsoft). Yesterday I picked up my conference badge... which incorporates a full Raspberry Pi with a battery, color screen, WiFi and bluetooth. GitHub Universe has a tradition of hackable conference badges - th...

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Quoting Aaron Boodman

Claude doesn't make me much faster on the work that I am an expert on. Maybe 15-20% depending on the day.

It's the work that I don't know how to do and would have to research. Or the grunge work I don't even want to do. On this it is hard to even put a number on. Many of the projects I do with Claude day to day I just wouldn't have done at all pre-Claude.

Infinity% improvement in productivity on those.

Aaron Boodman

Tags: ai-assisted-programming, claude, generative-ai, ai, llms, aaron-boodman

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The PSF has withdrawn a $1.5 million proposal to US government grant program

The PSF has withdrawn a $1.5 million proposal to US government grant program The Python Software Foundation was recently "recommended for funding" (NSF terminology) for a $1.5m grant from the US government National Science Foundation to help improve the security of the Pytho...

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GenAI Image Editing Showdown

GenAI Image Editing Showdown Useful collection of examples by Shaun Pedicini who tested Seedream 4, Gemini 2.5 Flash, Qwen-Image-Edit, FLUX.1 Kontext [dev], FLUX.1 Kontext [max], OmniGen2, and OpenAI gpt-image-1 across 12 image editing prompts. The tasks are very neatly sele...

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Sora might have a 'pervert' problem on its hands

Sora might have a 'pervert' problem on its hands Katie Notopoulos turned on the Sora 2 option where anyone can make a video featuring her cameo, and then: I found a stranger had made a video where I appeared pregnant. A quick look at the user's profile, and I saw that this ...

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Setting up a codebase for working with coding agents

Someone on Hacker News asked for tips on setting up a codebase to be more productive with AI coding tools. Here's my reply: Good automated tests which the coding agent can run. I love pytest for this - one of my projects has 1500 tests and Claude Code is really good at sele...

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Quoting Claude Docs

If you have an AGENTS.md file, you can source it in your CLAUDE.md using @AGENTS.md to maintain a single source of truth.

Claude Docs, with the official answer to standardizing on AGENTS.md

Tags: coding-agents, anthropic, claude, claude-code, generative-ai, ai, llms

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Visual Features Across Modalities: SVG and ASCII Art Reveal Cross-Modal Understanding

Visual Features Across Modalities: SVG and ASCII Art Reveal Cross-Modal Understanding New model interpretability research from Anthropic, this time focused on SVG and ASCII art generation. We found that the same feature that activates over the eyes in an ASCII face also act...

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claude_code_docs_map.md

claude_code_docs_map.md Something I'm enjoying about Claude Code is that any time you ask it questions about itself it runs tool calls like these: In this case I'd asked it about its "hooks" feature. The claude_code_docs_map.md file is a neat Markdown index of all of their ...

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Quoting Geoffrey Litt

A lot of people say AI will make us all "managers" or "editors"...but I think this is a dangerously incomplete view! Personally, I'm trying to code like a surgeon. A surgeon isn't a manager, they do the actual work! But their skills and time are highly leveraged with a supp...

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OpenAI no longer has to preserve all of its ChatGPT data, with some exceptions

OpenAI no longer has to preserve all of its ChatGPT data, with some exceptions

This is a relief:

Federal judge Ona T. Wang filed a new order on October 9 that frees OpenAI of an obligation to "preserve and segregate all output log data that would otherwise be deleted on a going forward basis."

I wrote about this in June. OpenAI were compelled by a court order to preserve all output, even from private chats, in case it became relevant to the ongoing New York Times lawsuit.

Here are those "some exception":

The judge in the case said that any chat logs already saved under the previous order would still be accessible and that OpenAI is required to hold on to any data related to ChatGPT accounts that have been flagged by the NYT.

Via Theo Browne

Tags: law, new-york-times, privacy, ai, openai, generative-ai, llms

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Quoting AWS

For resiliency, the DNS Enactor operates redundantly and fully independently in three different Availability Zones (AZs). [...] When the second Enactor (applying the newest plan) completed its endpoint updates, it then invoked the plan clean-up process, which identifies plan...

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Video: Building a tool to copy-paste share terminal sessions using Claude Code for web

This afternoon I was manually converting a terminal session into a shared HTML file for the umpteenth time when I decided to reduce the friction by building a custom tool for it - and on the spur of the moment I fired up Descript to record the process. The result is this new...

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Dane Stuckey (OpenAI CISO) on prompt injection risks for ChatGPT Atlas

My biggest complaint about the launch of the ChatGPT Atlas browser the other day was the lack of details on how OpenAI are addressing prompt injection attacks. The launch post mostly punted that question to the System Card for their "ChatGPT agent" browser automation feature...

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Living dangerously with Claude

I gave a talk last night at Claude Code Anonymous in San Francisco, the unofficial meetup for coding agent enthusiasts. I decided to talk about a dichotomy I've been struggling with recently. On the one hand I'm getting enormous value from running coding agents with as few r...

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SLOCCount in WebAssembly

SLOCCount in WebAssembly This project/side-quest got a little bit out of hand. I remembered an old tool called SLOCCount which could count lines of code and produce an estimate for how much they would cost to develop. I thought it would be fun to play around with it again, ...

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Don't let Claude Code delete your session logs

Claude Code stores full logs of your sessions as newline-delimited JSON in ~/.claude/projects/encoded-directory/*.jsonl on your machine. I currently have 379MB of these!

Here's an example jsonl file which I extracted from my Deepseek-OCR on NVIDIA Spark project. I have a little vibe-coded tool for converting those into Markdown which produces results like this.

Unfortunately Claude Code has a nasty default behavior of deleting these after 30 days! You can't disable this entirely, but you can at least delay it for 274 years by adding this to your ~/.claude/settings.json file:

{
  "cleanupPeriodDays": 99999
}

Claude Code's settings are documented here.

Tags: coding-agents, anthropic, claude-code, generative-ai, ai, llms

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Unseeable prompt injections in screenshots: more vulnerabilities in Comet and other AI browsers

Unseeable prompt injections in screenshots: more vulnerabilities in Comet and other AI browsers The Brave security team wrote about prompt injection against browser agents a few months ago (here are my notes on that). Here's their follow-up: What we’ve found confirms our in...

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Introducing ChatGPT Atlas

Introducing ChatGPT Atlas Last year OpenAI hired Chrome engineer Darin Fisher, which sparked speculation they might have their own browser in the pipeline. Today it arrived. ChatGPT Atlas is a Mac-only web browser with a variety of ChatGPT-enabled features. You can bring up ...