Scheme 48 is an implementation of the Scheme programming language as described in the Revised5 Report on the Algorithmic Language Scheme [6]. It is based on a compiler and interpreter for a virtual Scheme machine. Scheme 48 tries to be faithful to the Revised5 Scheme Report, providing neither more nor less in the initial user environment. (This is not to say that more isn't available in other environments; see below.)

Scheme 48 is under continual development. Please report bugs, especially in the VM, especially core dumps, to Include the version number x.yy from the "Welcome to Scheme 48 x.yy" greeting message in your bug report. It is a goal of this project to produce a bullet-proof system; we want no bugs and, especially, no crashes. (There are a few known bugs, listed in the doc/todo.txt file that comes with the distribution.)

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The name `Scheme 48' commemorates our having written the original version in forty-eight hours, on August 6th and 7th, 1986.