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.

NJSON aims to make it convenient for one to decode, encode, and process JSON data, in the minimum keystrokes/minutes possible.

NJSON is parser-independent, with existing Common Lisp JSON parsers being loadable as additional system. jzon is included by default, though. Conveniences that NJSON provides are:

• encode and decode as single entry points for JSON reading and writing, be it from streams/string/files, or from those.

• jget, jcopy, jkeys, and their aliases to manipulate the decoded objects' properties without the need to worry about the low-level details of how these values are decoded.

• jif, jwhen, jor, jand, and other macros mimicking Lisp ones, while using truth values of JSON-decoded data.

• jbind and jmatch macros to destructure and validate parsed JSON.

• njson/aliases package to nickname to j for all the forms conveniently accessible as j:get, j:copy, j:if etc.

(X)HTMLambda is yet another (X)HTML library which emphasizes programmability and user-friendliness. Each (X)HTML element is a structured object and pretty-printing of (X)HTML trees is well defined to provide properly indented human-readable output even for complex recursive arrangements.

An implementation of the exponential backoff algorithm in Common Lisp. Inspired by the implementation found in Chromium. Read the header file to learn about each of the parameters.

This is a Common Lisp library to extract EXIF information from image files.

cl-rucksack is a persistence library based on Arthur Lemmens' Rucksack with some enhancements.

This is a Common Lisp library for solving linear programming problems.

This is a Common Lisp wrapper for libjpeg-turbo library which provides TurboJPEG API for compressing and decompressing JPEG images.

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.

FLARE is a library designed to allow quick and precise particle effect creations. It does not concern itself with displaying and only with the management and movement of particles. As such, it can easily be integrated into any existing or future application.

This library provides the FORMGREP function and related utilities which find top-level Lisp forms matching the regular expression corresponding to an operator name, returning the matched forms and the names of the files and the line numbers where they were found.

This package implements binary trees of various kinds, presenting a uniform interface to them all.

BORDEAUX-THREADS is a proposed standard for a minimal MP/Threading interface. It is similar to the CLIM-SYS threading and lock support.

Envy is a configuration manager for various applications. Envy uses an environment variable to determine a configuration to use. This can separate configuration system from an implementation.

This is a library to provide cross-platform access to gamepads, joysticks, and other such HID devices.

core-gp is a Common Lisp library for genetic programming (GP) algorithms. It allows standard GP, strongly-typed GP, grammatical evolution as well as standard genetic algorithms.

This Common Lisp library converts strings, symbols and keywords between any of the following typographical cases: PascalCase, camelCase, snake_case, kebab-case (lisp-case).

Doctests for Lisp.

CL-UNICODE is a portable Unicode library Common Lisp, which is compatible with perl. It is pretty fast, thread-safe, and compatible with ANSI-compliant Common Lisp implementations.

This package provides GNU gettext completely implemented in Common Lisp without any C library bindings.

fare-utils is a small collection of utilities. It contains a lot of basic everyday functions and macros.

UBIQUITOUS is a very easy-to-use library for persistent configuration storage. It automatically takes care of finding a suitable place to save your data, and provides simple functions to access and modify the data within.

This package provides a functionality augmenting Hunchentoot error pages and logs with request and session information.

This Common Lisp library implements the quoted-printable encoding as described in RFC 2045 (see http://tools.ietf.org/html/rfc2045).