I'm a long term Mac developer and have been on the Mac Pro from when it was called the PowerMac G4. In recent years, however, Apple has failed to deliver my new Mac Pro every 3 years and I’ve been forced to try lots of different strategies: By now I have a 2014 iMac in my office, a 2013 hex-core Mac Pro in my home office and a Late 2016 MacBook Pro 15” to roam around with. I’m mostly working on my MacBook Pro at the moment, but later in the summer my new home office will be ready and I’ll go back to working mostly on a desktop. I’m a 3 big screens kind of developer, so a laptop is not a great fit for me. Now with the new Kaby Lake iMac out, the iMac Pro due in December and the new Mac Pro some time off, I’m trying to figure out what to do. On the one hand, the new iMac 27” fully specced out is actually a fantastic machine trouncing all of my current Macs with 5,692 single and 19,478 multi-core performance, which is 74% faster on single, and 5% faster on multi-core than my Mac Pro. On the other hand an 18 core iMac Pro is only a few months away, and the new Mac Pro is certain to go even further, though it’s ETA is up in the clouds. I’m mostly interested in Xcode (and AppCode) performance and it is really hard to predict its performance on different architectures. I know Xcode is CPU bound, but only up to the point where the disk and the RAM can’t shovel data in and out quickly enough. I found some old benchmarks online, but there aren’t really enough to get a clear picture. My fully specced out Skylake MacBook Pro 15” 4-core is a smidgen faster than my Mac Pro already. The MacBook Pro has 16Gb of memory v. the Mac Pro’s 12Gb, the SSD is twice as fast, it is a good 20% faster on single core tasks but 28% slower on multi-core tasks. I would spec a new iMac with at least 16Gb of RAM and its disk is supposed to be 50% faster than the previous generation, so probably at least on a par with the 2x of the MacBook Pro. The question is what does all that amount to? As far as I can see the iMac Pro ships with at least 32Gb of memory, but it is quite possible that it has the same SSD speed. Starting at 8 cores, I’m already wondering whether even the base model can shovel the data in and out fast enough to keep the cores working. What is the likelihood of 2 or 8 additional cores being used at all? Looking at Intel’s range, it is clear that the more cores, the less highly clocked the CPU can be. That means that an 8-, 10- or 18-core Xeon machine is likely to get nowhere near the i7’s single thread performance. Does all this amount to making the i7 iMacs faster for Xcode than the Mac Pro? If so, there’s no point in waiting till December and beyond. If I’ve learned anything from 20 years as a Mac users is that prices don’t fall before a new machine goes out, so you’re best off buying as soon as it is released to get most life out of it. To make things worse, Coffee Lake is due out later this year and is said to offer around 30% increase in performance at the same clock speed.. but will Apple update the iMacs again before long? or leave the iMac Pro in clear air for a while longer? Your thoughts would be appreciated.