Vert
Drop a GPX track, get a 3D terrain poster. Nothing you upload leaves your browser.
Always exploring.
I'm Sean, a frontend engineer who was writing code by hand long before AI could, with a soft spot for data visualization. Most of what I build is for fun, or to make life a little lazier.
Writing here since 2011: 106 essays
Projects
Explorable
Paste a paper or a blog post, get a short essay whose figures you can drag.
Reasontrail
How a coding agent got there: the session as a tree, subagents as limbs, tool calls as twigs.
Activities
Every session I have recorded since 2020, drawn as the shape it left behind.
Repo Rivers
A repository's history as rivers: modules and people widen, merge and split over the years.
Worldlines, Art-isms, Dialectica
Three reading atlases: world history, art movements, philosophy.
markvis
Charts straight from Markdown; one word changes the kind of chart. 1.6k stars, now an Obsidian plugin.
spec2skill
Turn an OpenAPI spec or an MCP server into a tested agent skill, with a map to check what it teaches.
Pagelapse
How any web page changed over the years, from its Internet Archive captures.
Also timeline-sankey, a Sankey that flows along time, hand-written D3. More on GitHub
Writing
Off screen
Running is the hobby with the most data: 1,702 km logged in Hong Kong between 2020 and 2022, and one UTMB series stone, earned at Translantau 50. Bouldering, up to V9. Tennis: I can rally; the serve is still a project. A ukulele to sing along to, and a ten-hole harmonica for simple tunes, no bends yet.
Two kids, and a podcast in Chinese, Beyond Code.