Simon Willison — Week of 2026-06-12 to 2026-06-18#

Highlight of the Week#

The most impactful release this week is the launch of datasette-apps, a major new plugin that allows developers to run self-contained, sandboxed HTML and JavaScript applications directly against a persistent Datasette backend. It brilliantly merges Simon’s ongoing experiments with AI-generated “vibe-coded” single-file tools and robust security architectures, pushing Datasette from a read-only publishing platform into a comprehensive ecosystem for building interfaces over data.

Simon Willison — Week of 2026-06-18 to 2026-06-25#

Highlight of the Week#

This week’s absolute standout is the launch of the datasette-apps plugin, which fundamentally transforms how we build micro-applications over local databases. By utilizing tightly constrained iframe sandboxes and Content-Security-Policy headers, developers and LLMs alike can safely run custom HTML/JS interfaces against a persistent Datasette backend. It brilliantly merges Simon’s ongoing experiments with AI-assisted “vibe coding” and robust security architectures into a core ecosystem feature, effectively bridging the gap between Claude Artifacts and secure data environments.

Simon Willison — 2026-06-13#

Highlight#

The most substantive update today explores the major Pyodide 314.0 release that finally allows publishing WASM wheels directly to PyPI. This eliminates a massive bottleneck for the Python-in-the-browser ecosystem, and Simon immediately proved its value by using AI tools to package and ship a C++ based WebAssembly experiment.

Posts#

Publishing WASM wheels to PyPI for use with Pyodide With Pyodide 314.0, developers can now publish Python packages built for Pyodide directly to PyPI, removing a major hurdle where maintainers previously had to manually review and host over 300 packages themselves. To celebrate, Simon used Codex and GPT-5.5 xhigh to package his experimental C++ Luau WebAssembly project, successfully building and deploying it via GitHub Actions. True to form, he then used ChatGPT to draft a BigQuery SQL query to explore PyPI’s dataset, discovering that 28 packages are already utilizing the new pyemscripten_202*_wasm32 tags.

Simon Willison — 2026-06-23#

Highlight#

The standout news today is a massive step forward for Datasette’s mutation capabilities in the 1.0a35 release, introducing powerful new graphical interfaces for creating and altering tables. This shifts Datasette further from its read-only roots toward a full-fledged database management UI.

Posts#

datasette 1.0a35 Simon dropped a major pre-release for Datasette that introduces powerful new “Create table” and “Alter table” graphical interfaces, complete with their own backing JSON APIs. Users can now seamlessly define columns, NOT NULL constraints, and foreign keys, or modify existing tables by adding, dropping, or reordering columns directly from the UI. Additionally, the release formalizes the template context variables, generated directly from dataclass definitions, into a stable API for custom template authors to use until Datasette 2.0. Simon also shared a quick video demo walking through the new table mutation features.