An isomorphic BASIC language compiler for retrocomputers by Marco Spedaletti.

A cross compiler of BASIC dialect specialized in programs that are very efficient "by design" on various 8-bit platforms (based on MOS 6502/6510, Motorola 6809 and Zilog Z80), without the need for "fine tuning" them and without compromises of other dev-kits.

In addition to numerous fixes and space-time optimizations, this release adds support for five additional home computers: the Commodore 16 (c16), the Dragon 32/64 (d32b, d64b), and the TANDY CORPORATION COCO 1/2/3 (cocob, coco3b). These latter computers are equipped with a new processor, the HITACHI 6309, for which a series of specific improvements and optimizations have been introduced.
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A new version of ugBASIC, the open-source isomorphic BASIC compiler, has been released.
In addition to numerous fixes and optimizations for the Amstrad CPC 664, the language has had numerous improvements, with dynamic strings in user-defined types, the use of BIT as a data primitive, virtual ATLASes, and screen writing with custom fonts.
ugBASIC is a cross-compiler for Linux and Windows for writing BASIC games, running on dozens of different home computers and 8-bit consoles. There's also a convenient built-in IDE for Microsoft Windows and even a sandbox if you don't want to install anything.