Aider has many options which can be set with command line switches. Most options can also be set in an .aider.conf.yml file which can be placed in your home directory or at the root of your git repo. Or via environment variables like AIDER_xxx, as noted in the options reference.

Here are 3 equivalent ways of setting an option. First, via a command line switch:

$ aider --dark-mode

Or, via an env variable:

export AIDER_DARK_MODE=true

Or in the .aider.conf.yml file:

dark-mode: true

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