$ apt-cache show postgresql-9.4 | grep ^Depends
Depends: libc6 (>= 2.16), libgssapi-krb5-2 (>= 1.8+dfsg), libldap-2.4-2 (>= 2.4.7), \
libpam0g (>= 0.99.7.1), libpq5 (>= 9.1~), libssl1.0.0 (>= 1.0.0), libxml2 (>= 2.7.4), \
postgresql-client-9.4, postgresql-common (>= 142~), tzdata, ssl-cert, locales

$ aptly mirror create -architectures=amd64 -filter=postgresql-9.4 -filter-with-deps m1 \
  http://deb.debian.org/debian jessie main

$ aptly mirror update  -dep-verbose-resolve m1
Downloading http://deb.debian.org/debian/dists/jessie/InRelease...
...
Applying filter...
Missing dependencies: libc6 (>= 2.16) [amd64], libgssapi-krb5-2 (>= 1.8+dfsg) [amd64], \
libldap-2.4-2 (>= 2.4.7) [amd64], libpam0g (>= 0.99.7.1) [amd64], \
libpq5 (>= 9.1~) [amd64], libssl1.0.0 (>= 1.0.0) [amd64], libxml2 (>= 2.7.4) [amd64], \
postgresql-client-9.4 [amd64], postgresql-common (>= 142~) [amd64], tzdata [amd64], \
ssl-cert [amd64], locales [amd64]
Injecting package: libc6_2.19-18+deb8u10_amd64
Injecting package: libgssapi-krb5-2_1.12.1+dfsg-19+deb8u2_amd64
Injecting package: libldap-2.4-2_2.4.40+dfsg-1+deb8u3_amd64
Injecting package: libpam0g_1.1.8-3.1+deb8u2+b1_amd64
Injecting package: libpq5_9.4.12-0+deb8u1_amd64
Injecting package: libssl1.0.0_1.0.1t-1+deb8u6_amd64
Injecting package: libxml2_2.9.1+dfsg1-5+deb8u4_amd64
Injecting package: postgresql-client-9.4_9.4.12-0+deb8u1_amd64
Injecting package: postgresql-common_165+deb8u2_all
Injecting package: tzdata_2017b-0+deb8u1_all
Injecting package: ssl-cert_1.0.35_all
Injecting package: locales-all_2.19-18+deb8u10_amd64
...

$ aptly mirror show -with-packages m1 | grep locales
  locales-all_2.19-18+deb8u10_amd64