fenrir is a console screen reader similar in features to espeakup or
speechd-up, that can uses voices available through Speech Dispatcher or
espeak-ng.

Currently it has to be run as root. The script /etc/rc.c/rc.fenrir
allows to manage the fenrir daemon.

To have fenrir-dameon running at startup, type as root:
switch-on fenrir
This will also disable espeakup and speech-up that conflict with fenrir.

See also:
man service
man service setup

More importantly, to know how to (re)configure and use fenrir:
man fenrir

The configuration file, adapted to Slint is:
/etc/fenrirscreenreader/settings/settings.conf
The genuine (unmodified) configuration file is:
/etc/fenrirscreenreader/settings/settings.conf.genuine
You can take it as a basis and customize it if you prefer.
The configuration file read by fenrir is the one named settings.conf,
so a customized one has to be (re)named like that to be used.

By default the voice is set as mbrola en1 through Speech Dispatcher in
Slint, but you may change that in the configuration file.

To list the synthesizers available:
spd-say -O
To list languages and synthesizers available:
spd-list
To list the voices available through a given synthesizer:
spd-say -o <synthesizer> -L
For instance for the mbrola voices:
spd-say -o espeak-ng-mbrola-generic -L