Embeddable Common Lisp

Embeddable Common Lisp
Paradigms	Multi-paradigm: procedural, functional, object-oriented, meta, reflective, generic
Family	Lisp
Designed by	Giuseppe Attardi
Developers	Daniel Kochmański, Marius Gerbershagen
First appeared	1 January 1995 (1995-01-01)
Stable release	26.3.271  / 27 March 2026
Typing discipline	Dynamic, strong
Implementation language	C, Common Lisp
Platform	ARM, x86
OS	Unix-like, Android, Windows
License	LGPL 2.1+
Website	ecl.common-lisp.dev
Influenced by
Lisp, Common Lisp, C

Embeddable Common Lisp (ECL) is a small implementation of the ANSI Common Lisp programming language that can be used stand-alone or embedded in extant applications written in C.² It creates OS-native executables and libraries (i.e. Executable and Linkable Format (ELF) files on unix) from Common Lisp code, and runs on most platforms that support a C compiler. The ECL runtime is a dynamically loadable library for use by applications. It is distributed as free software under a GNU Lesser Public License (LGPL) 2.1+.

It includes a runtime system, and two compilers, a bytecode interpreter allowing applications to be deployed where no C compiler is expected, and an intermediate language type, which compiles Common Lisp to C for a more efficient runtime. The latter also features a native foreign function interface (FFI), that supports inline C as part of Common Lisp. Inline C FFI combined with Common Lisp macros, custom Lisp setf expansions and compiler-macros, result in a custom compile-time C preprocessor.