Tried building the Dockerfile directly as that seems to be the only semi-official support, but ran into various issues. I'm on ARM, so can't use zknt as others have mentioned. Switched to another Pixelfed image murazaki/pixelfed:edge-apache; but get the following error:

pixelfed-app       | PHP Warning:  require_once(/var/www/bootstrap/app.php): Failed to open stream: No such file or directory in /var/www/artisan on line 20
pixelfed-app       | PHP Fatal error:  Uncaught Error: Failed opening required '/var/www/bootstrap/app.php' (include_path='.:/usr/local/lib/php') in /var/www/artisan:20
pixelfed-app       | Stack trace:
pixelfed-app       | #0 {main}
pixelfed-app       |   thrown in /var/www/artisan on line 20

Seems to be hinted at in a Github issue, but not finding the line to edit: https://github.com/pixelfed/pixelfed/issues/2080#issuecomment-631086578

Looks like the devs don't actively maintain the docker image, per this GitHub issue. I found some people saying they are building it locally and some people saying they are using this unofficial repo.

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