This page lists common problems and work-arounds.

This page needs expansion! If you encounter a new problem and solve it, feel free to add it here. If you encounter a problem you don't know how to solve, try asking on Stack Overflow, and be sure to add the "sandstorm.io" tag to your question. Or, talk to us on IRC (#sandstorm on freenode) or sandstorm-dev.

Note that language-specific issues should be documented in the language-specific guide pages, namely:

Sandstorm apps cannot navigate the user away from the app. Therefore, app authors should set target="_blank" on links within the app.

A convenient way to do this automatically for all links in the page is to add the following HTML to your document's <head>:

<base target="_blank">

A blank white screen renders where the app should be

This can happen when a Sandstorm app in development doesn't know its correct base URL and serves a HTTP redirect away from the Sandstorm server. Sandstorm blocks that redirect, resulting in a white grain frame.

To find out if you're running into this issue, open the Javascript console in your browser and look for a Content-Security-Policy violation. If you see a message about navigation being blocked, then very likely you are seeing this error.

If possible, configure the app to use a base URL of '', literally the empty string. Then it will send HTTP redirects without specifying a base URL. If that isn't possible, Sandstorm apps should look at the

Sandstorm apps should look at the Host: header for a base URL if they need one.

KeyError: 'getpwuid(): uid not found: 1000'

This is a Python bug. See the Python packaging guide for a work-around.

EROFS or "Read-only filesystem"

Only the /var directory is writable; the rest of the filesystem (which contains the contents of your app package) is read-only.

If your app wants to write to locations other than /var, and it's not easy to change the app's code, one work-around is to create a symlink from the location you app wants to modify to a location under /var. This won't work for all applications however.