[lispm]

> The Scopes compiler fundamentally differs from C++ and other traditional AOT (ahead of time) compilers, in that the compiler is designed to remain on-line at runtime so that functions can be recompiled when the need arises, and generated machine code can adapt to the instruction set present on the target machine. This also diminishes the need for a build system. Still, Scopes is not a JIT compiler. Compilation is always explicitly initiated by the user.

Many Lisp systems also have their native code compiler on-line.