Being engaged or married as such doesn't make any difference, since INZ judges 'partnership' as a live-in relationship, and that's what has to be proved, in ways mentioned officially here
http://www.immigration.govt.nz/migra...artnership.htm, and on various old threads on the forum you can find with the Search.
If you have both been offered skilled jobs that will entitle you to temporary work visas (is this an accredited employer?), that's certainly one good way of doing it. On the other hand, as long as one of you is getting a temporary work visa, as long as you have evidence of your partnership as mentioned above, s/he could sponsor the other for a partner-sponsored temporary work visa, matching the first for length of time, and that's another good way of doing it.
http://www.immigration.govt.nz/migra...milystream.htm This is done by sending in both applications together at the same time, linked by a covering letter, then the CO works both things as one case, supplying things you wouldn't know to begin with, like the first person's visa number, as they become available.
When once you have your two work visas, by either route, if you want to go for Residence, you can put in one application for both of you, one being the principle applicant and naming the partner.
http://www.immigration.govt.nz/migra...nt/default.htm If you do this fairly soon, you would probably be able to use some of the same evidence used for your work visas.