GCL

I recently tried out GCL, a Compiler and interpreter for Common Lisp, and was impressed with its capabilities. One of the standout features is that GCL compiles to C, leveraging the native optimizing C compiler (e.g., GCC) for great portability. This approach also results in high efficiency, with function calls being essentially the same speed as C function calls—indeed, identical to C function calls via a pointer.

Additionally, GCL includes a source level Lisp debugger (dbl) for interpreted code. This debugger allows you to step through code one line at a time, with your position displayed in an Emacs window. GCL has pioneered conservative Garbage Collection schemes, which provide efficient memory management. However, the software also has a more recent stratified garbage collection (SGC) scheme, specifically designed for recent allocations and based on native page fault handling.

GCL also features a built-in interface to Tk widget system, which enables a mixture of tcl and Common Lisp for user interface development according to your preferences. Overall, I found GCL to be a highly capable tool for Common Lisp development, with features that make it both efficient and highly accessible.