=> Bootstrap dependency digest>=20010302: found digest-20121220
=> Checksum SHA1 OK for twin-src-3.1.14.tar.gz
=> Checksum RMD160 OK for twin-src-3.1.14.tar.gz
===> Installing dependencies for twin-3.1.14nb4
=> Tool dependency gmake>=3.81: found gmake-3.82nb6
=> Build dependency x11-links>=0.72: found x11-links-0.74
===> Overriding tools for twin-3.1.14nb4
===> Extracting for twin-3.1.14nb4
===> Patching for twin-3.1.14nb4
=> Applying pkgsrc patches for twin-3.1.14nb4
===> Creating toolchain wrappers for twin-3.1.14nb4
ERROR: zlib>=1.1.4nb1 is not installed; can't buildlink files.
*** Error code 1

Stop.
bmake: stopped in /usr/pkgsrc/emulators/twin
*** Error code 1

Stop.
bmake: stopped in /usr/pkgsrc/emulators/twin