Cal Henderson
Web developer; former head of engineering at Flickr, author of Building Scalable Web Sites, and co-founder and CTO of Slack.
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19 October
14 September
1 September
17 August
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6 January
6 January 2025
12 February 2024
16 January 2024
12 September 2023
27 February 2023
9 January 2023
26 May 2022
5 January 2022
25 October 2021
22 July 2021
14 May 2021
1 January 2021
6 October 2020
31 August 2020
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Recommends rcmnd
rcmnd What they recommend 9 things — each backed by an exact quote.
Compiled by rcmnd.app, not by them: the quotes are theirs, and each links to the post it was copied from.
Recent
Uses Windows XP Professional
On my PC I run Windows XP Professional; Vista is a bit too high-tech for me.
usesthis.com 26 Nov 2009
Loved Paint Shop Pro 5
I use Paint Shop Pro 5 from 1998 for working with graphics - it is still the best program ever made for dealing with images at the pixel level and converting between formats.
usesthis.com 26 Nov 2009
Uses Evernote
For keeping in sync between my Mac and my PC, I use XMarks for bookmarks and Evernote for notes.
usesthis.com 26 Nov 2009
Show 6 more
Liked Miranda
mIRC is for IRC, Miranda is for everything else. I used Trillian for a few years, but it became more and more bloated. Miranda starts quickly and uses very little memory.
usesthis.com 26 Nov 2009
Recommends phpMyAdmin
One of the best pieces of software in a web developer's toolbox is phpMyAdmin, which no LAMP developer should be without.
usesthis.com 26 Nov 2009
Liked Antec cooling pad
but I've recently got an Antec cooling pad that seems to work fine, once you cover the crazy-bright LED with electrical tape.
usesthis.com 26 Nov 2009
Loved Ikea Jerker
Both of my machines sit on a pair of Ikea Jerker desks, the best cheap computer desks ever made. You should be sad if you never bought one before they stopped making them.
usesthis.com 26 Nov 2009
Liked Sony MDR7506
For music on my PC, I have a pair of Sony MDR-7506 headphones that are comfortable enough to wear all day without getting squished ears. They sound pretty good too.
usesthis.com 26 Nov 2009
Mixed on Bose Companion 5
I have a really nice sounding pair of Bose Companion 5's, but they don't work well with OSX - they cut out when switching apps and need unplugging and replugging
usesthis.com 26 Nov 2009
Where they publish
Site iamcal.com Personal site, writing and side projects.
Link verified 5 Sept 2026.
x.com @iamcal His X account.
Recent
- I've updated my 2025 reading list with the 121 books I read in the year. Highlights were The Thursday Murder Club by @richardosman, Piranesi by @susannaclarke_, The Repeat Room by Jesse Ball and Little Eyes by @sschweblin. 6 Jan 2026 iamcal.com
- I've updated my 2024 reading list with the 88 books I read in the year. Highlights were Oryx and Crake by @MargaretAtwood, The Husbands by @hollygramazio and Dungeon Crawler Carl by @mattdinniman 6 Jan 2025 iamcal.com
- Happy 10th birthday to Slack 🎉 Happy 20th birthday to Flickr 🎉 Time for me to take a little break 😅 12 Feb 2024
Show 16 more
- I've updated my 2023 reading list with the 105 books I read in the year. Highlights were The Future, by @NaomiAllthenews, Station Eternity by @mightymur and Titanium Noir by @Harkaway 16 Jan 2024 iamcal.com
- This is so much fun! 12 Sept 2023
- Ok, maybe 3D printing is actually really cool 27 Feb 2023
- I've updated my 2022 reading list with all the 112 books I read in the year. Highlights were Tomorrow, and Tomorrow, and Tomorrow, by @gabriellezevin and A Memory Called Empire by @ArkadyMartine. 9 Jan 2023 iamcal.com
- @dunepod Best Dan Ackroyd movies are obviously Dragnet and Grosse Pointe Blank. Not sure how you missed those. 26 May 2022
- My favorite books of 2021 were The First Fifteen Lives of Harry August by @ClaireNorth42 and The Deficit Myth by @StephanieKelton 5 Jan 2022
- @goldman so glad that someone else noticed they switched from meters to feet in the lesson book. I’m hoping that was a goof and not an intentional commentary about still having the imperial systems after 10,000 years 25 Oct 2021
- After 12+ years of being an independent company, today Slack joined Salesforce. Together, we’re going to do great things. Let’s go! 22 Jul 2021
- The CDC says fully vaccinated people can keep their video turned off for zoom calls 14 May 2021
- RIP Flash Player. End of an era 😢 1 Jan 2021
- Some amazing leaders have joined @SlackHQ! Welcome, Fuzzy Khosrowshahi, Product Eng VP; @Rukmini_Reddy, Platform Eng VP; and Sean Catlett, CSO. To hear more about the future of Slack that we’re building together, join us for Frontiers 2020, tomorrow: 6 Oct 2020 slack.com
- Excited to be talking to @Bandrew at Brits by the Bay on Sept 17th 31 Aug 2020
- it's all about communication and support. don't treat remote workers as second class citizens. run better meetings. record decisions. make sure people are building relationships #AskTwitterEng 15 May 2020
- i think it's important to separate working from home more generally, with the current crisis. people who are having to care for their children, look after family, have a poor working setup, or are very socially isolated are unfairly impacted right now #AskTwitterEng 15 May 2020
- Talk to as many people as you can. Read everything available. Take part in as many virtual 'social' activities as possible. So much of what you get out of an internship is about what you put in, and that requires much more effort when you're remote. #AskTwitterEng 15 May 2020
- hmm, good question. much of the prior literature has really been about evangelizing remote work, rather than practical advice for either making the transition abruptly as we just have, or the accelerated transition we'll see over the next few years #AskTwitterEng 15 May 2020
Link verified 5 Sept 2026. Recent items update automatically from the channel.
GitHub @iamcal Open source libraries and Flickr-era code.
Recent
- autolink-js — JS link formatting library 20 Oct 2026
- ease.js — Easing functions for natural animation, in JavaScript. 20 Oct 2026
- homespring.js — A JavaScript interpreter for Homespring 20 Oct 2026
Show 17 more
- js-emoji — A JS Emoji conversion library 20 Oct 2026
- lib_timezones — Sensible Timezone Selection 20 Oct 2026
- oembed — The oEmbed Spec 19 Oct 2026
- emoji-data — Easy to parse data and spritesheets for emoji 14 Sept 2026
- SQLParser — Parse MySQL schemas in PHP, fast 1 Sept 2026
- battlepetdata.com 17 Aug 2026
- enchant-order — Minecraft enchantment optimization tool 17 Aug 2026
- code.iamcal.com — Random bits of code from the last 20 years 1 May 2026
- lib_sanitize — PHP input filtering library 1 May 2026
- timezone.help 30 Apr 2026
- c4.citycreator.com 30 Apr 2026
- InsanityTracker — A web app to track players who gain the achievement Insane in the Membrane in World of Warcraft 30 Apr 2026
- londonbloggers — A revamp of the london bloggers directory 30 Apr 2026
- updog.report — what's updog? 30 Apr 2026
- rss-manip 29 Apr 2026
- unicodey.com — Unicode tools 28 Apr 2026
- World-of-MapCraft — World of Warcraft Slippy Maps 28 Apr 2026
Link verified 5 Sept 2026. Recent items update automatically from the channel.
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