Things I've learned, collected in simonw/til. You may also enjoy my blog.
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My blog was showing poor performance, with some pages taking several seconds to load or even failing entirely. …
Inspired by Armin, I decided to figure out how to use the official microsoft/playwright-mcp Playwright MCP server with Claude Code. …
One of our cameras takes raw photos in ORF format, which I believe stands for "Olympus Raw Format". Here's a recipe I found for converting them to JPEG on macOS: …
Microsoft recently released Edit, a new terminal text editor written in Rust. It's pretty nice - it's reminiscent of nano but with a retro MS DOS feel. …
I wanted to redirect https://global-power-plants.datasettes.com/ to https://datasette.io/ - I decided to spin up a Cloudflare Pages site to do the work. …
I use pytest-httpx in a bunch of my projects. Occasionally I run into test failures like this one, which can sometimes be really hard to figure out: …
I wrote a Python script, triggers.py, to help me understand what data is available to SQLite triggers for which operations. …
I figured out a minimal pattern for building a completely custom website using GitHub Actions and deploying the result to GitHub Pages. …
I've been experimenting with the HTML dialog element recently, for example in my Prompts.js JavaScript library. …
I tried to get jupyterlab working via uv tool install today and ran into some sharp edges. …
For an (ethical) scraping project I found that my low-volume scraper was working from my laptop but was being blocked by Cloudflare when I attempted to run it in GitHub Actions, presumably because the GitHub Actions IP range was disallowed. …
This is a three-quarters-baked experiment that I ran this morning. I'm interested in efficiently tracking which new files have been added to an S3 bucket, where that bucket could potentially hold millions of items. …
I figured out a really simple pattern for experimenting with new Python packages today: …
While working on this issue I figured out a neat pattern for running the tests for my project locally against a specific Python version using uv run: …
Rhet Turnbull shared this short script for looking up the named timezone for a given location from Python on macOS using objc and the CoreLocation framework. It uses the objc package and pyobjc-framework-CoreLocation. …
TikTok may or may not be banned in the USA within the next 24 hours or so. Here's a pattern you can use to download all of the videos from a specific account. …
I wanted to know how large the deepseek-ai/DeepSeek-V3-Base repo on Hugging Face was without actually downloading all of the files. …
I was exploring the original BERT model from 2018, which is mainly useful if you fine-tune a model on top of it for a specific task. …
I was getting the following warning for one of my Python test suites: …
Here's what I learned about publishing a single file JavaScript package to NPM for my Prompts.js project. …
My tools.simonwillison.net site is a growing collection of small HTML and JavaScript applications hosted as static files on GitHub Pages. …
I really like Cog (previously) as a tool for automating aspects of my Python project documentation - things like the SQL schemas shown on the LLM logging page. …
I was experimenting with wasmtime-py today and found the current documentation didn't quite give me the information that I needed. …
If you ever run into instructions that tell you to do this: …
I finally figured out a process that works for me for hacking on Python CLI utilities using uv to manage my development environment, thanks to a little bit of help from Charlie Marsh. …
I ran https://simonwillison.net/ through PageSpeed Insights and it warned me that my static assets were not being served with browser caching headers: …
I'm still working towards adding multi-modal support to my LLM tool. In the meantime, here are notes on running prompts against images and PDFs and audio and video files from the command-line using the Google Gemini family of models. …
With Claude's help I figured out what I think is the most basic version of a static site generated using Hugo. …
I live in El Granada, California. Wikipedia calls us a census designated place - we don't have a mayor or city council. But we do have a Community Services District - originally responsible for our sewers, and since 2014 also responsible for our parks. And we get to vote for the board members in the upcoming November election! …
I managed to get my Homebrew installation back into shape today. The first problem I was having is that it complained that macOS Sequoia was unsupported: …