Version 9.5.1 of Icon is available in source and binary form. For details about the changes in this version, see the release notes.
Icon runs on Unix-like systems, including Linux, BSD, and Macintosh. Icon can run within the Cygwin environment on Microsoft Windows.
Documentation is on line:
Precompiled binaries are available for the Unix systems listed below. These binaries are built with graphics enabled, so the X Window system must be present on the target platform. Each package includes the translator, interpreter, interface builder, and library procedures. To install Icon from binaries,
Binary packages are 1.5 MB gzipped tar files.
gunzip <file.tgz | tar xf –.
The source code package is a 3.1 MB gzipped tar file that includes the complete Icon program library. It can be configured for most Unix platforms including Cygwin and Darwin.
Source code for the latest development version of Icon — the current work in progress — can be downloaded in source code form from GitHub