J systems are available for a number of platforms and can be installed and redistributed for free.
J is available as a base system plus optional addon packages.
The base system is the minimal system for running J applications. It includes two user interfaces:
- Jconsole, a command-line front-end
- JHS, a browser-based IDE
A Qt-based IDE is also available in the addons.
Once a J release or beta system is installed, all updates to addons, base library, and binaries can be done with the J package manager.
New users should install the J807 release. Experienced users can install J901 beta with System/Installation/Zips install.
J807 64-bit systems are available for hardware with or without AVX, see Guides/AVX. The default is AVX, while the non-AVX version installers have "nonavx" in the name, e.g. j807_win64_nonavx.exe.
J901 64-bit systems require AVX hardware.
Most modern CPUs support the AVX instructions, but if you are unsure, try the AVX version first. Any failure will probably be reported as "Illegal instruction" when starting J, in which case install the non-AVX version.
Most Windows or Mac users will want to use the All-in-One install.
Linux users who want a debian package should use the Linux deb install.
Android users should use the Android apk install.
Experienced users who want more control, use System/Installation/Zips install.