Is digging graves a deed for which the doer is rewarded, or is it not among the practices of the Salaf?

It is well-known that all that is necessary for the deceased, such as washing, shrouding, carrying, praying over, and burying, falls under communal obligations (fard al-kifaya) that Muslims must perform. The one who performs them is rewarded, and if a sufficient number of people perform them, the sin is lifted from the rest. However, if all of them abandon these duties, they all incur sin. Your act of digging graves is a form of assistance and contribution to the burial of the dead, and this does not diminish its goodness and desirability.