- Apple II archaeology - Apple II archaeology is a collection of Lisp code useful for Apple II retrocomputing
- armish - Armish is an arm assembler
- Assem - Assem is an ISA-level code layer for Common Lisp
- BITMOP - BITMOP is a DSL for definition and manipulation of register sets, registers, bitfields and bitfield values, all of which are first-class objects
- cl-comfy-arm - cl-comfy-arm is an implementation by JosephOswald of Henry Baker's COMFY assembler for the ARM architecture
- cl-elf - cl-elf is a library for reading and writing the ELF executable file format
- CL-IO-ELF - CL-IO-ELF is a parser for ELF executable file format
- cl-larval - S-Exp syntax to write assembler for AVR microcontrollers
- COMFY-6502 - COMFY-6502 is a port by JosephOswald of Henry Baker's COMFY-6502 compiler to Common Lisp
- LLVM - LLVM stands for Low Level Virtual Machine
- swap-bytes - swap-bytes is a library for efficient endianness conversion in SBCL and CCL
- SYMTABLE - SYMTABLE is a simplistic symbol-table abstraction
machine code
Assemblers, disassemblers, machine code debuggers, etc.