Debugging

Below are some common steps to take when facing issues with the developer environment.

Reload the Developer Environment

If your developer environment either fails to launch or does not pick up a desired change, simply run nix-direnv-reload to trigger a reload.

Sometimes, the caching provided by nix-direnv might prevent your changes from appearing. For a hard reload, run direnv reload.

Nested Shells

Sometimes direnv may not load and unload the shell properly. This can lead to starting multiple nested shells which can break some utilities. If you are unsure whether you are in this state, simply exit and relaunch the terminal.

New File Not Found

If you are adding new files into your developer environment, you MUST first track them with git via git add <file> in order for them to visible to the nix build system.

This can manifest as an error that looks like:

error: getting status of '<file>': No such file or directory

No Column Named Domain

error: creating statement 'insert or replace into Cache(domain, key, value, timestamp) values (?, ?, ?, ?)': SQL logic error, table Cache has no column named domain (in '/home/user/.cache/nix/fetcher-cache-v2.sqlite')

This can occur after upgrading for version of the nix binary.

To resolve, run rm -f ~/.cache/nix/fetcher-cache-v2.sqlite. This will allow the cache DB to be recreated with the correct schema.