If your Linux system use deb packages,see Installation on Ubuntu, Debian.

On Fedora you can use ccdciel, qt5pas and libpasastro packaged with the system.

On Gentoo Linux use the overlay available here: https://github.com/jamesbates/gentoo-overlay

For other Linux system you can download rpm or tar packages from the Sourceforge download link.

The requirement are Qt5, LibQt5Pas and libpasastro.

See also the list of dependencies to install to take full advantage of the software.

You can also compile the source code using Lazarus.

To open DSLR raw files you need the library libpasraw to interface with LibRaw.
Unfortunately the LibRaw programming interface is not stable across LibRaw version, so libpasraw must be build specifically for your system or it not work.

For Ubuntu you can simply install libpasraw from this PPA:
https://launchpad.net/~pch/+archive/ubuntu/ppa-skychart

For a few other system you can find a package at:
https://github.com/pchev/libpasraw/releases

For other system you need to compile and install libpasraw from source after installing the libraw-dev package. See https://github.com/pchev/libpasraw/blob/master/README.md

As a last resort you can install the libraw-bin or dcraw package, but this is less performant as it need to work with temporary files.