# Commit 2021-10-25 22:55 c363ad63

View on Github →feat(category_theory/sites/*): Cover preserving functors (#9691) Split from #9650

- Defined
`cover_preserving`

functors as functors that push covering sieves to covering sieves. - Defined
`compatible_preserving`

functors as functors that push compatible families to compatible families. - Proved that functors that are both
`cover_preserving`

and`compatible_preserving`

pulls sheaves to sheaves.