SCM is a free software Scheme implementation in C written by Aubrey Jaffer, the same author as the SLIB Scheme library and the JACAL interactive symbolic mathematics program.It conforms to the R4RS, R5RS, and IEEE P1178 standards.It runs on many different architectures such as Amiga, GNU/Linux, Atari-ST, Mac OS (SCM Mac), MS-DOS, OS/2, NOS/VE, Unicos, VMS, Unix and similar systems.SCM includes Hobbit, the Scheme-to-C compiler originally written by Tanel Tammet.Hobbit generates C files whose binaries can be dynamically or statically linked with an SCM executable.SCM includes linkable modules for SLIB features like sequence comparison, arrays, records, and byte-number conversions.