A hook, in the present context, is a certain kind of extension point in a program that allows interleaving the execution of arbitrary code with the execution of a the program without introducing any coupling between the two. Hooks are used extensively in the extensible editor Emacs.

In the Common LISP Object System (CLOS), a similar kind of extensibility is possible using the flexible multi-method dispatch mechanism. It may even seem that the concept of hooks does not provide any benefits over the possibilities of CLOS. However, there are some differences:

• There can be only one method for each combination of specializers and qualifiers. As a result this kind of extension point cannot be used by multiple extensions independently.

• Removing code previously attached via a :before, :after or :around method can be cumbersome.

• There could be other or even multiple extension points besides :before and :after in a single method.

• Attaching codes to individual objects using eql specializers can be cumbersome.

• Introspection of code attached a particular extension point is cumbersome since this requires enumerating and inspecting the methods of a generic function.

This library tries to complement some of these weaknesses of method-based extension-points via the concept of hooks.

Event Emitter provides an event mechanism like Node.js for Common Lisp objects. It is mostly ported from Node.js events module.

This package provides simple format directives to print in colors.

GECO (Genetic Evolution through Combination of Objects) is an extensible, object-oriented framework for prototyping genetic algorithms in Common Lisp.

This is a Common Lisp library providing logging faciltiy similar to CL-LOG and LOG4CL.

Opticl is a Common Lisp library for representing, processing, loading, and saving 2-dimensional pixel-based images.

Overlord is a build system in Common Lisp. It is a real build system, with all the modern features: rules with multiple outputs, parallel builds, immunity to clock issues, and dynamic dependencies.

But Overlord is more than another build system. Overlord is a uniform approach to dependencies inside or outside of a Lisp image. Overlord is to Make what Lisp macros are to C macros.

Overlord is designed to be used from the Lisp REPL. A command line interface is available in a separate repository. See https://github.com/ruricolist/overlord-cli.

Cells is a mature, stable extension to CLOS allowing one to create classes whose instances can have slot values determined by instance-specific formulas.

This package provides some condition classes, functions and macros which may be useful when building slightly complex systems.

This package provides a SDL2 based vector graphic library for Common Lisp.

This package provides functions for base32 encoding and decoding as defined in RFC4648.

Porter Stemming Algorithm.

This is a native Common Lisp graphics math library with an emphasis on performance and correctness.

This library provides functions for determining the value types of Common Lisp forms, based on type information contained in the environment.

In order for this library to work the values types of variables and return types of functions have to be declared.

Macros and symbol-macros are fully expanded and all special forms, except CATCH, are supported.

This library strives to provide a portable TCP/IP and UDP/IP socket interface for as many Common Lisp implementations as possible, while keeping the abstraction and portability layer as thin as possible.

Bind extends the idea of of let and destructing to provide a uniform syntax for all your accessor needs. It combines let, destructuring-bind, with-slots, with-accessors, structure editing, property or association-lists, and multiple-value-bind and a whole lot more into a single form.

This Common Lisp library provides utilities for the Bodge library collection.

Babel is a charset encoding and decoding library, not unlike GNU libiconv, but completely written in Common Lisp.

This library lets you build a metaclass which in turn lets you specify extra slot options in its classes. Options may be easily inspected and custom inheritance may be set up. The Meta-Object Protocol (MOP) is used for the implementation - through closer-mop. Some convenience function for processing slot options are also available.

Possible use case: you want to automatically set up some definitions based on some slots, but you want to have control over it right in the class definition.

This Common Lisp library provides optimized byte-swapping primitives. The library can change endianness of unsigned integers of length 1/2/4/8. Very useful in implementing various network protocols and file formats.

This is a Common Lisp library to load images in the PNG image format, both from files on disk, or streams in memory.

LLA is a high-level Common Lisp library built on BLAS and LAPACK, but providing a much more abstract interface with the purpose of freeing the user from low-level concerns and reducing the number of bugs in numerical code.

This is a utility kit for functionality related to OpenGL. It provides the following:

• kit.glm: This re-exports sb-cga and mathkit for convenience.

• kit.gl.shader: This provides shader dictionary and compilation functionality similar to what was originally found in sdl2kit.

• kit.gl.vao: This provides an interface for Vertex Array Objects.

This is a Common Lisp library providing various utilities.