The Bordeaux-FFT library provides a reasonably efficient implementation of the Fast Fourier Transform and its inverse for complex-valued inputs, in portable Common Lisp.

This library provides a modern project skeleton generator. In contract with other generators, CL-Project generates one package per file and encourages unit testing by generating a system for unit testing, so you can begin writing unit tests as soon as the project is generated.

UCONS is a Common Lisp library providing unique conses. Unique conses are different from regular conses in that, in addition to their car and cdr, they maintain a table of past users. Also, the cdr of each ucons is restricted to other uconses or nil. Uconses are meant for those situations where even reusing regular conses (to avoid consing) is too computationally expensive.

A library for encoding text in various web-savvy encodings.

This Common Lisp package provides a regular expression engine.

This library provides a wrapper type for secret values, to reduce the risk of accidentally revealing them.

postmodern is a Common Lisp library for interacting with PostgreSQL databases. It provides the following features:

• Efficient communication with the database server without need for foreign libraries.

• Support for UTF-8 on Unicode-aware Lisp implementations.

• A syntax for mixing SQL and Lisp code.

• Convenient support for prepared statements and stored procedures.

• A metaclass for simple database-access objects.

This package produces 4 systems: postmodern, cl-postgres, s-sql, simple-date

SIMPLE-DATE is a very basic implementation of date and time objects, used to support storing and retrieving time-related SQL types. It is not loaded by default and you can use local-time (which has support for timezones) instead.

S-SQL is used to compile s-expressions to strings of SQL code, escaping any Lisp values inside, and doing as much as possible of the work at compile time.

CL-POSTGRES is the low-level library used for interfacing with a PostgreSQL server over a socket.

POSTMODERN itself is a wrapper around these packages and provides higher level functions, a very simple data access object that can be mapped directly to database tables and some convenient utilities. It then tries to put all these things together into a convenient programming interface

Portability library for IEEE float features that are not covered by the Common Lisp standard.

Plump is a parser for HTML/XML-like documents, focusing on being lenient towards invalid markup. It can handle things like invalid attributes, bad closing tag order, unencoded entities, inexistent tag types, self-closing tags and so on. It parses documents to a class representation and offers a small set of DOM functions to manipulate it. It can be extended to parse to your own classes.

This package provides a trivial line-input library for VT-like terminals.

Implementation of a set-like data structure with constant time addition, removal, and random selection.

This package provides Common Lisp FFI bindings for libwayland, primarily for the mahogany window manager.

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.

MODULARIZE is an attempt at providing a common interface to segregate major application components. This is achieved by adding special treatment to packages. Each module is a package that is specially registered, which allows it to interact and co-exist with other modules in better ways. For instance, by adding module definition options you can introduce mechanisms to tie modules together in functionality, hook into each other and so on.

This is an extension to MODULARIZE that allows your application to define interfaces in-code that serve both as a primary documentation and as compliance control.

one-more-re-nightmare is a regular expression engine that uses the technique presented in Regular-expression derivatives re-examined (Owens, Reppy and Turon, 2009; doi:10.1017/S0956796808007090) to interpret and compile regular expressions.

ZPB-TTF is a TrueType font file parser that provides an interface for reading typographic metrics, glyph outlines, and other information from the file.

Authentic provides a light-weight and extendible solution to user/password management for Common Lisp applications. It has features such as safe password storage in a database, password reset, user confirmation tokens, and user authentication.

This is a collection of common cryptography functions for Common Lisp.

A Common Lisp library for computing differences between sequences based on the Python difflib module.

This package provides a Common Lisp translation library similar to CL-I18N and CL-L10N.

This package provides an implementation of a base 16 builder for Common Lisp.

Simple color library for Common Lisp.

On Cliki.net <http://www.cliki.net/Common%20Lisp%20Utilities>, there is a collection of Common Lisp Utilities, things that everybody writes since they're not part of the official standard. There are some very useful things there; the only problems are that they aren't implemented as well as you'd like (some aren't implemented at all) and they aren't conveniently packaged and maintained. It takes quite a bit of work to carefully implement utilities for common use, commented and documented, with error checking placed everywhere some dumb user might make a mistake.