Here are the requirements: 280 apm broken down into 80 macro and 200 micro, all of which are fully needed for a quality implementation of SK should it come to that. Adaptability for when the improbable but inevitable happens. Lose nothing unnecessarily. Chinese triangles.
Here is the build: B, C (plant on site), bunk if needed, B, R, acad, ebay, and then develop in a linear fashion up to facility with no dropship. If zerg goes 3 bases, go SK, delaying 2nd ebay and/or irrad if needed to comfortably exceed the zerg's hive output with raw vessel count - losing the first vessel and then having 3 of them vs 4 defilers is a bad thing. If zerg goes 3 base lurker in an attempt to stall, get two tanks and come out and win, only slower. If zerg goes 4 bases, move out with 3T 1V and triangle and win. If zerg 2hatches, deal with it.
Why the build dominates: Twin scanners allow for a perfect read nullifying any direct mutabal variant. You have a hard counter for 4 base zerg (build order win). If the zerg goes 3 bases, you will eventually win via SK. Power and tech = stage and advance with twin vessels. Power and mass = 2 tanks if lurker else stage and advance on his 3rd. Mass and tech = stage and advance on his main with triangle and defiler snipe. If the zerg goes 2 bases, no amount of mechanics should allow him to overpower you without control errors on your part.
Here are the zerg options. I will disregard obvious junk builds (3 base hydra/lurker, retard drop variants etc.):
9 pool burrow rush to delay CC plant and subsequent 2nd scanner -> 2 hatch 1.05 lurker ling. Cut the scouting scvs with rapidity (which will be almost impossible), and you better not be on SinChup if you try this. Attack the front. GL.
10 speedling runby. The delayed hive puts zerg in a position where they are faced with, at best, vessel domination over hive. 4 base is an autoloss, in an even more brutal fashion than normally. More mutas are met with even more turrets and rapidly upgraded marines and the zerg is left with, again, vessel domination over hive. Kill 4 workers or gg.
1.05 2 hatch speedling -> mutabal with grades. Luxury played this recently with good results (in relative terms). The order shows promise, except for on maps like SinChup where it's just impossible to win. Z has to kill the initial scouting scv quickly and then cut the next one enroute. With perfect control it's arguable that this is a strong order, possibly the only order, as the zerg can reduce the Terran to his main as the minerals are not available for a 2nd bunker by default, and on a map like Andro, if the Z can dramatically reduce marine count he has the option to mutaling allin to siege the barracks directly, or to drone and take a 3rd and lurker siege. This would force T to choose between an allin 2nd wave or to develop and take his chances vs guards with merely competitive vessel numbers.
Old school JulyZerg. See above, but easier.
3 hatch mutabal -> guards. See the Mah replay.
5pool. Use it.