By email: josh@klar.sh or josh@joshklar.com are fine. Use +fromwebsite if you want the best odds of delivery, but it’s not required. My response time for emails is typically measured in days to weeks in the winter, and almost always 1+ weeks in the summer unless it is clearly urgent.

By IRC: klardotsh on libera.chat or esper.net, if I’m online. Typical for IRC, don’t assume my scrollback or offline delivery works: if I see your message, I’ll respond when I can, and otherwise, if it was important, probably send me an email follow-up shortly thereafter. If your inquiry can’t fit within two or three IRC messages, it almost certainly needs to be an email instead.

If you want to hit me up on Mastodon, go for it. Similar guidelines about message length apply as with IRC, but I tend to be decent about responding to short things within a couple days to a week on there.