Skip to content


@w3c @whatwg @w3ctag @web-platform-tests @googlers
Block or Report

Block or report dbaron

Block user

Prevent this user from interacting with your repositories and sending you notifications. Learn more about blocking users.

You must be logged in to block users.

Report abuse

Contact GitHub support about this user’s behavior. Learn more about reporting abuse.

Report abuse

I'm currently (since March 2021) a software engineer at Google working on rendering in Blink.

I was a software engineer at Mozilla from 2003-2020, working on the Gecko layout engine, with a focus on implementing new CSS and layout features, making architectural changes to improve speed and memory use, building tools to debug memory use and memory leaks, analyzing automated crash report submissions, general debugging and bug fixing, driving projects to successful completion, and mentoring of both junior and senior engineers in many of these areas.

I've also been a longtime participant in work on Web standards: this includes participation in the W3C's CSS Working Group, being an elected member of the W3C's Technical Architecture Group, longtime involvement at a technical and standards policy level in both the W3C and WHATWG, and helping others at Mozilla interact with these standards bodies and with other companies participating in them.

Code hosted here

The code I host in this github account (not counting forks of other repositories) falls into a few categories:

Proposals for Web standards:

Tools used within the W3C:

  • wgmeeting-github-ircbot - IRC bot to make github comments with relevant sections of Working Group Meeting IRC minutes
  • gather-doc-email - Python script to gather email for a W3C disposition of comments

Documentation about CSS:

  • inlines-and-floats - Document describing interaction of inline layout and wrapping around floats

Code related to timezones:

  • tz.js - A library for working with timezones in JavaScript
  • tzmap.js - A library for working with the geography of timezones in JavaScript
  • timezone-map - A Web-based map of timezones as they are at a point in time, using both tz.js and tzmap.js.
  • meeting-scheduler - Web application for figuring out what time a meeting is in multiple timezones. (A demonstration of tz.js use.)

Some mapping-related code I've written:

  • osm-satellite-scripts - Scripts for processing satellite images for use in mapbox studio for tracing with OpenStreetMap iD editor
  • osm-area-diff - Diff OpenStreetMap changes in a time period to help understand and revert vandalism
  • walk-maps - A leaflet-based map of GPX traces of walks I've taken (without the private data)
  • backpacking-maps - A leaflet-based map of GPX traces of backpacking trips I've taken
  • rail-network-quizzes - code to use OpenStreetMap data to build rail network quizzes for JetPunk

Some other simple Web applications I've written:

Some Mozilla extensions I've written:

A Mercurial extension I wrote:

  • qfixdrift - Mercurial extension to clean up patch drift in an mq patch queue

My Gecko patch development from 2007 to 2018 lives in these Mercurial Queue repositories:

My Gecko patch development from 2019-2020 lives on branches in my fork of gecko.

I also have a Mercurial Queue repository of patches to the CSS Working Group's specs:

Other Mozilla-related repositories:

Other code I've written:

Code hosted elsewhere

Most of the code I've written is not hosted in this GitHub account; it lives elsewhere. This includes contributions to:


  1. Proposal for container queries designed to be implementable in web browsers

    45 1

  2. Specification of features for even spacing of lines in CSS.


  3. IRC bot to make github comments with relevant sections of Working Group Meeting IRC minutes. Running as @css-meeting-bot.

    Rust 13 14

  4. Character Identifier is a Web Extension that adds a browser context menu item for selected text that provides more information (from the Unicode database) about the characters selected.


  5. tz.js Public

    A library for working with timezones in JavaScript. Used as part of .

    Python 25 7

  6. Analyzing the Ranked Choice Voting (RCV) of 2008-2019 San Francisco elections.

    HTML 3 3

176 contributions in the last year

Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Mon Wed Fri
Activity overview
Contributed to web-platform-tests/wpt, w3c/csswg-drafts, dbaron/wgmeeting-github-ircbot and 17 other repositories

Contribution activity

July 2022

Created an issue in tabatkins/css-toggle that received 1 comment

toggle creation/replacement model is a bit unclear

3. Creating a Toggle: the toggle-root property says: In addition to specifying how to create new toggles, a toggle specifier overrides the existin…

1 comment

Seeing something unexpected? Take a look at the GitHub profile guide.