When installing J9.7 on macOS Sequoia 15.7.3, I unpack the ZIP release in my home directory under ~/Applications/Free. After unpacking the contents, I end up with these files: $ unzip $HOME/Downloads/j9.7_mac64.zip […] $ tree -L1 j9.7/ j9.7/ ├── addons ├── bin ├── jbrk.app ├── jcon.app ├── jhs.app ├── jqt.app ├── macos-fix.command ├── readme.txt ├── system ├── tools ├── updateje.sh └── updatejqt.sh 9 directories, 4 files The updatejqt.sh should install JQt for me but you'll see it fail with a mysterious tar error here: $ cd j9.7 ~/A/F/j9.7$./updatejqt.sh Updating server catalog... Installing 1 package Downloading base library... Installing base library... Done. Installing JQt slim binaries... gzip: unknown compression format tar: Child returned status 1 tar: Error is not recoverable: exiting now Finished install of JQt slim binaries. Installing Qt library... Finished install of Qt library. My instinct tells me that this is because I use Nix coreutils on my system through nix-darwin. This means that the gzip and tar commands on my computer aren't macOS and BSD-derived programs, but the GNU coreutils commands that you'll often use on a Linux distribution. I notice that the util/pacman.ijs module in J is responsible for downloading and unpacking files. I assume that the root cause of the tar and gzip error comes from a bad mixture of if branches in the following code: NB. util/pacman.ijs NB. https://github.com/jsoftware/jsource/blob/master/jlibrary/system/util/pacman.ijs www=. 'https://www.jsoftware.com/download/j',RELNO 'rc p'=. httpget_jpacman_ www,'/qtide/',z if. rc do. smoutput 'unable to download: ',z return. end. d1=. d=. jpath '~bin' if. IFWIN do. unzip_jpacman_ p;d else. if. FHS do. if. (<UNAME)e.'Darwin';'OpenBSD';'FreeBSD' do. d1=. (({.~ i:&'/')BINPATH),'/lib/' elseif. IFRASPI do. d1=. (({.~ i:&'/')BINPATH),IF64{::'/lib/arm-linux-gnueabihf/';'/lib/aarch64-linux-gnu/' elseif. do. if. -.fexist d1=. (({.~ i:&'/')BINPATH),IF64{::'/lib/i386-linux-gnu/';'/lib/x86_64-linux-gnu/' do. d1=. (({.~ i:&'/')BINPATH),IF64{::'/lib/';'/lib64/' end. end. echo 'install libjqt.',suffix,' to ',d1 hostcmd_jpacman_ 'rm -f ',BINPATH,'/jqt' echo 'cd ',(dquote jpath '~temp'),' && tar --no-same-owner --no-same-permissions -xzf ',(dquote p), ' && chmod 755 jqt && mv jqt ',BINPATH,'/jqt-',RELNO,' && cp libjqt.',suffix,' ',d1,'/libjqt.',vsuffix,' && chmod 755 ',d1,'/libjqt.',vsuffix, ((<UNAME)e.'Linux';'OpenBSD';'FreeBSD')#' && /sbin/ldconfig' hostcmd_jpacman_ 'cd ',(dquote jpath '~temp'),' && tar --no-same-owner --no-same-permissions -xzf ',(dquote p), ' && chmod 755 jqt && mv jqt ',BINPATH,'/jqt-',RELNO,' && cp libjqt.',suffix,' ',d1,'/libjqt.',vsuffix,' && chmod 755 ',d1,'/libjqt.',vsuffix, ((<UNAME)e.'Linux';'OpenBSD';'FreeBSD')#' && /sbin/ldconfig' if. 'Linux'-:UNAME do. echo 'update-alternatives --install ',BINPATH,'/jqt jqt ',BINPATH,'/jqt-',RELNO,' ',RELNO,' || true' hostcmd_jpacman_ 'update-alternatives --install ',BINPATH,'/jqt jqt ',BINPATH,'/jqt-',RELNO,' ',RELNO,' || true' end. else. hostcmd_jpacman_ 'cd ',(dquote d),' && tar xzf ',(dquote p) end. end. ferase p if. #1!:0 FHS{::(BINPATH,'/',z1);BINPATH,'/jqt' do. m=. 'Finished install of ',bin else. m=. 'Unable to install ',bin,LF m=. m,'check that you have write permission for: ',LF,BINPATH end. smoutput m linux=. (UNAME -: 'Linux') *. 907 <: VERNO When you make changes to this file, running the updatejqt.sh script reverts those changes. Similarly, directly running bin/jconsole -js "exit install 'slim'" reverts my changes to util/pacman.ijs. Since I can't change or fix pacman.ijs, I have to find another workaround. The solution is to adjust your PATH environment variable to not include any Nix-installed GNU coreutils. Here's that PATH before, formatted for legibility: $ printenv PATH /etc/profiles/per-user/debian/bin: /run/current-system/sw/bin: /nix/var/nix/profiles/default/bin: /Users/debian/.local/bin: /Users/debian/.dotfiles/bin: /Users/debian/.cargo/bin: /Users/debian/.nix-profile/bin: /usr/local/bin: /usr/bin: /bin: /usr/sbin: /sbin You need to run updatejqt.sh with just the last four /bin or /sbin directories and it works: PATH='/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin' ./updatejqt.sh When the installer runs correctly, you'll see this: Updating server catalog... Installing 1 package Downloading base library... Installing base library... Done. Installing JQt slim binaries... Finished install of JQt slim binaries. Installing Qt library... Finished install of Qt library. Exit and restart J using the jqt icon Make sure to run macos-fix.command, too. Run ./macos-fix.command, too Open in new tab (full image size 24 KiB) Enjoy array programming with J on macOS! j9.7.1 and JQt running on macOS Sequoia Open in new tab (full image size 36 KiB)