While a number of Mac developers have already moved on to even more modern shells like Fish, zsh is more compatible with Bourne shell (sh) and mostly compatible with bash. Apple has kept clear of using GPLv3 packages in macOS as the license is generally more restrictive to companies like Apple that sign their own code and it includes explicit patent grants, too. Apple is stuck using version 3.2 of bash that has been licensed under GPLv2, as newer versions are licensed under GPLv3. Bash will still be available, but Apple is signaling that developers should start moving to zsh on macOS Mojave or earlier in anticipation of bash eventually going away in macOS.Īpple hasn’t explained exactly why it’s making this change, but bash isn’t exactly a modern shell as it’s implemented in macOS, and a switch to something less aging makes a lot more sense for the company. All newly created user accounts in macOS Catalina will use zsh by default. Starting with macOS Catalina, Macs will now use zsh as the default login shell and interactive shell across the operating system. Apple unveiled macOS Catalina yesterday with support for iPad apps and lots of new features, but a big change for developers and power users was missing from the on stage presentation.
