[geerlingguy]

Alternate anecdata, I've never seen someone use it outside of Facebook/Meta. I'm sure some people did but PHP 7 solved the performance issues people had with PHP 5, and PHP 8 nuked some of the footguns people complained about all the time, to the point, the few shops who looked at Hack / HHVM (and weren't switching to another language entirely) just stayed on PHP.

[evanelias]

Not sure of the status today, but Slack is/was one of the most high-profile non-Facebook users of Hack, e.g. https://slack.engineering/hacklang-at-slack-a-better-php/

[znpy]

The post is from four years ago however, does anybody have an update on that topic?

[evanelias]

Slack has a few eng blog posts from last year which seem to indicate they still use Hack, among other languages.

https://slack.engineering/hakana-taking-hack-seriously/ describes their open source enhanced Hack type checker, which is still actively maintained (most recent commit yesterday).

And https://slack.engineering/slacks-migration-to-a-cellular-arc... mentions they use a mix of languages: "services in the user-facing request path are written in Hack, Go, Java, and C++"

[psanford]

As of the beginning of this year, slack still used a lot of hhvm.