Simon Willison’s Weblog

A CGo-free port of SQLite. Fascinating Go version of SQLite, which uses Go code that has been translated from the original SQLite C using ccgo, a package by the same author which “translates cc ASTs to Go source code”. It claims to pass the full public SQLite test suite, which is very impressive. # 30th January 2022, 10:25 pm

Mypyc (via) Spotted this in the Black release notes: “Black is now compiled with mypyc for an overall 2x speed-up”. Mypyc is a tool that compiles Python modules (written in a subset of Python) to C extensions—similar to Cython but using just Python syntax, taking advantage of type annotations to perform type checking and type inference. It’s part of the mypy type checking project, which has been using it since 2019 to gain a 4x performance improvement over regular Python. # 30th January 2022, 1:31 am

Black 22.1.0 (via) Black, the uncompromising code formatter for Python, has had its first stable non-beta release after almost four years of releases. I adopted Black a few years ago for all of my projects and I wouldn’t release Python code without it now—the productivity boost I get from not spending even a second thinking about code formatting and indentation is huge.

I know Django has been holding off on adopting it until a stable release was announced, so hopefully that will happen soon. # 30th January 2022, 1:23 am

The baseline for web development in 2022 (via) “TL;DR:The baseline for web development in 2022 is: low-spec Android devices in terms of performance, Safari from two years before in terms of Web Standards, and 4G in terms of networks. The web in general is not answering those needs properly, especially in terms of performance where factors such as an over-dependence on JavaScript are hindering our sites’ performance.” # 27th January 2022, 8:09 pm

Two reasons Kubernetes is so complex (via) I like how this article proposes that Kubernetes isn’t trying to be a tool for deploying containers—it’s more like an operating system for a cluster of machines, responsible for the same kind of goals as a regular operating system such as resource sharing and portability. And since everything is built as control loops which attempt to modify actual state to fit the declarative desired state, errors can occur asynchronously seconds or even minutes after the desired state has been updated. # 27th January 2022, 6:25 pm

Observable Plot Cheatsheets (via) Beautiful new set of cheatsheets by Mike Freeman for the Observable Plot charting library. This is really top notch documentation—the cheatsheets are available as printable PDFs but the real value here is in the interactive versions of them, which include Observable-powered sliders to tweak the different examples and copy out the resulting generated code. # 25th January 2022, 10:12 pm

Roblox Return to Service 10/28-10/31 2021 (via) A particularly good example of a public postmortem on an outage. Roblox was down for 72 hours last year, as a result of an extremely complex set of circumstances which took a lot of effort to uncover. It’s interesting to think through what kind of monitoring you would need to have in place to help identify the root cause of this kind of issue. # 21st January 2022, 4:41 pm

How to Add a Favicon to Your Django Site (via) Adam Johnson did the research on the best way to handle favicons—Safari still doesn’t handle SVG icons so the best solution today is a PNG served from the /favicon.ico path. This article inspired me to finally add a proper favicon to Datasette. # 20th January 2022, 7:03 am

Tricking Postgres into using an insane – but 200x faster – query plan. Jacob Martin talks through a PostgreSQL query optimization they implemented at Spacelift, showing in detail how to interpret the results of EXPLAIN (FORMAT JSON, ANALYZE) using the explain.dalibo.com visualization tool. # 18th January 2022, 8:53 pm

SQLime: SQLite Playground (via) Anton Zhiyanov built this useful mobile-friendly online playground for trying things out it SQLite. It uses the sql.js library which compiles SQLite to WebAssembly, so it runs everything in the browser—but it also supports saving your work to Gists via the GitHub API. The JavaScript source code is fun to read: the site doesn’t use npm or Webpack or similar, opting instead to implement everything library-free using modern JavaScript modules and Web Components. # 17th January 2022, 7:08 pm

Abusing AWS Lambda to make an Aussie Search Engine (via) Ben Boyter built a search engine that only indexes .au Australian websites, with the novel approach of directly compiling the search index into 250 different ~40MB large lambda functions written in Go, then running searches across 12 million pages by farming them out to all of the lambdas and combining the results. His write-up includes all sorts of details about how he built this, including how he ran the indexer and how he solved the surprisingly hard problem of returning good-enough text snippets for the results. # 16th January 2022, 8:52 pm

Writing a minimal Lua implementation with a virtual machine from scratch in Rust. Phil Eaton implements a subset of Lua in a Rust in this detailed tutorial. # 15th January 2022, 6:29 pm

Announcing Parcel CSS: A new CSS parser, compiler, and minifier written in Rust! An interesting thing about tools like this being written in Rust is that since the Rust-to-WASM pipeline is well trodden at this point, the live demo that this announcement links to runs entirely in the browser. # 13th January 2022, 8:40 pm

Hashids (via) Confusingly named because it’s not really a hash—this library (available in 40+ languages) offers a way to convert integer IDs to and from short strings of text based on a salt which, if kept secret, should help prevent people from deriving the IDs and using them to measure growth of your service. It works using a base62 alphabet that is shuffled using the salt. # 8th January 2022, 7:31 pm