My thanks to Impending for sponsoring last week at DF to promote their new app, Walk the World. You surely know some of Impending’s other apps, like the innovative checklist/task app Clear. Walk the World turns your steps — your real-world activity — into a new kind of virtual globe-trotting adventure.

Wouldn’t it be cool to know you’ve walked the length of the Boston Marathon this past week? You can conquer iconic hikes and trails from around the world presented as gorgeous map milestones to complete with your hard earned steps. It’s a genuinely novel idea for gamifying activity, executed with an exquisite attention to detail and exuberant sense of joy. Walk the World isn’t quite a game, but it delivers game-like fun.

If you enjoy or aspire to go on walks more regularly, and beautiful indie apps with fun new twists, this is your new healthy addiction. Try Walk the World free today for your iPhone.

One more for my weekend spate of developer posts, but from the opposite of the LLM-assisted cutting edge: this wonderful collection of classic-era Mac programming books, carefully scanned as PDFs. These evoke nostalgia both for the classic Mac era and for the entire notion of “programming books”. (Via Michael Tsai and Rui Carmo.)

Sosumi.ai:

Ever notice Claude struggling to write Swift code? It might not be their fault!

Apple Developer docs are locked behind JavaScript, making them invisible to most LLMs. If they try to fetch it, all they see is “This page requires JavaScript. Please turn on JavaScript in your browser and refresh the page to view its content.”

This service translates Apple Developer documentation pages into AI-friendly Markdown.

Perfect little audio easter egg on the page. Beautiful Markdown output too. Look at my boy, all grown up, teaching robots how to program.

I do regret, though, that I didn’t define or influence the fenced style for code blocks. If I had, instead of this:

```swift
// An array of 'Int' elements
let oddNumbers = [1, 3, 5, 7, 9, 11, 13, 15]
```

You could do this, which looks so much better:

``` Swift:
// An array of 'Int' elements
let oddNumbers = [1, 3, 5, 7, 9, 11, 13, 15]
```

Those all-lowercase language identifiers, with no preceding space, just look a little lazy. I realize why GitHub’s ```-fenced code blocks took off (they’re the only code block style most Markdown users know, I suspect), but they don’t look nearly as nice, to human readers, as my original tab-indented style.

From Apple’s Xcode 26 Beta 7 release notes:

• Claude in Xcode is now available in the Intelligence settings panel, allowing users to seamlessly add their existing paid Claude account to Xcode and start using Claude Sonnet 4. (155826755)

• When using ChatGPT in Xcode, users can now start a new conversation with either GPT-4.1 or GPT-5, with GPT-5 set as the default. (158342780)

• ChatGPT in Xcode provides two model choices. “GPT-5” is optimized for quick, high-quality results, and should work well for most coding tasks. For difficult tasks, choose “GPT-5 (Reasoning)“, which spends more time thinking before responding, and can provide more accurate results for complex coding tasks.

  In the OpenAI API, “GPT-5” corresponds to the “minimal” reasoning level, and “GPT-5 (Reasoning)” corresponds to the “low” reasoning level. (159135374)

That’s just three weeks from the launch of ChatGPT 5 to shipping support in Xcode. Also, these are just the built-in integrations. As announced at WWDC, Xcode 26 allows developers to use their API keys from other AI providers, or connect to models running locally, on-device (if they’re using an Apple Silicon Mac).

Howard Oakley: Spotlight is so substantial, almost silent in the log, and impenetrable that the best approach to diagnosing its problems is to test it out in a controlled way. Mints has been doing that by creating a folder of files containing an unusual word, then searching for that. Although that’s still useful for a […]