Chibi-Scheme is a very small but mostly complete R5RS Scheme implementation using a reasonably fast custom VM. Chibi-Scheme tries as much as possible not to trade its small size by cutting corners, and provides full continuations, both low and high-level hygienic macros based on syntactic-closures, string ports and exceptions. Chibi-Scheme is written in highly portable C and supports multiple VM instances running simultaneously.
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