=> Bootstrap dependency digest>=20010302: found digest-20160304
===> Skipping vulnerability checks.
WARNING: No /var/db/pkg/pkg-vulnerabilities file found.
WARNING: To fix run: `/usr/sbin/pkg_admin -K /var/db/pkg fetch-pkg-vulnerabilities'.
===> Installing for ocaml-ppx_derivers-1.0
=> Generating pre-install file lists
opam-installer: not found
*** Error code 127

Stop.
make[1]: stopped in /data/pkgsrc/devel/ocaml-ppx_derivers
*** Error code 1

Stop.
make: stopped in /data/pkgsrc/devel/ocaml-ppx_derivers