common-lisp Hedgehog is a very concise implementation of a Lisp-like language for low-end and embedded devices. It consists of a compiler and a byte code interpreter. The byte code interpreter is written in standard conforming C, is efficient and easily portable, and can be compiled to a very small executable of only some 20 kilobytes in the smallest configuration for the Intel x86 architecture. The Hedgehog Lisp dialect has proper support for local and lambda functions, lexical scoping, variable argument functions, garbage collection, exceptions, macros, and over a hundred predefined functions or special forms. The built-in types are lists, symbols, strings, 32-bit integers, AVL-trees, and tuples up to 16 elements wide. Proper 32-bit wide integers are necessary for various bit-level operations in embedded systems.