There were two great shmups for mac.
One was the first 256 color game I ever saw running on a personal computer, with no music but good sound effects. It ran on a Mac LC (first model), and had right-to-left scrolling. The ship and background was seen from the side [I know many meet this description but I assume there mustn't be much games like this from that era, this was 1988 or 89 IIRC].
The second one was much more recent (1994 maybe), and was some kind of gyruss clone (i.e. the ship goes around the screen, like if it was in a tunnel). It's not tempest (very different graphical style), and not Maelstrom either. I remember that there was a level selection screen that reminds of Starfox (you choose which planets you travel to, and the levels are sections between the planets).
Rings any bells? :-)
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