SOURCE_DATE_EPOCH
variable in the
debian/rules
file.
.
As of dpkg 1.18.8, this is no longer necessary as dpkg exports this
variable if it is not already set. However, you can also include
/usr/share/dpkg/pkg-info.mk
or /usr/share/dpkg/default.mk
to ensure it is exported.
See-Also: https://reproducible-builds.org/specs/source-date-epoch/