ST-JSON (ST because it originated at Streamtech) is a Common Lisp library for encoding and decoding JSON values (as specified on json.org).

This library does mostly the same thing as CL-JSON, but is simpler and more precise about types (distinguishing boolean false, the empty array, and the empty object).

This package provides a SuperCollider client for Common Lisp.

CL-octet-streams is a library implementing in-memory octet streams for Common Lisp. It was inspired by the trivial-octet-streams and cl-plumbing libraries.

NDebug provides a small set of utilities to make graphical (or, rather non-REPL-resident) Common Lisp applications easier to integrate with the standard Lisp debugger (*debugger-hook*, namely) and implementation-specific debugger hooks (via trivial-custom-debugger), especially in a multi-threaded context.

Portable document preparation system.

This library is a path strings manipulation library inspired by Python's os.path. All functionality from os.path is supported on major operation systems.

The philosophy behind is to use simple strings and "dumb" string manipulation functions to handle paths and filenames. Where possible the corresponding OS system functions are called.

This library implements the base58 encoding algorithm. It's basically base64 but with a smaller alphabet (58, as in the name) that doesn't include similar looking characters, among other things. See https://github.com/bitcoin/bitcoin/blob/master/src/base58.h for a full reference.

This package provides an implementation of the Matrix API for Common Lisp.

Schemeish implements several useful Scheme constructs for Common Lisp. These include named-let, define, scheme argument lists, and a shortcut to FUNCALL with [] instead of ().

Dynamic-Classes helps to ease the prototyping process by bringing dynamism to class definition.

with-user-abort is a Common Lisp portability library providing a like-named macro that catches the SIGINT signal.

Coalton is a dialect of ML embedded in Common Lisp. It emphasizes practicality and interoperability with Lisp, and is intended to be a DSL that allows one to gradually make their programs safer.

PARSER-COMBINATORS is a library implementing monadic parser combinators in Common Lisp, similar in concept to Haskell Parsec system.

A miniature toolkit that contains some useful shifting/popping/pushing functions for arrays and vectors. Originally from Plump.

This library allows macro writers to provide better feedback to macro users when errors are signaled during macroexpansion. It uses the compiler's concept of a source-form to report where the error or warning is located.

Cl-async is a library for general purpose, non-blocking programming in Common Lisp. It uses the libuv library as backend.

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.

Maiden is a collection of systems to help you build applications and libraries that interact with chat servers. It can help you build a chat bot, or a general chat client. It also offers a variety of parts that should make it much easier to write a client for a new chat protocol.

HTML-TEMPLATE is a Common Lisp library which can be used to fill templates with arbitrary (string) values at runtime. The result does not have to be HTML.

It is loosely modeled after the Perl module HTML::Template and partially compatible with a its syntax, though both libraries contain some extensions that the other does not support.

HTML-TEMPLATE translates templates into efficient closures which can be re-used as often as needed. It uses a cache mechanism so you can update templates while your program is running and have the changes take effect immediately.

This package provides a portability layer for the extensible sequences standard extension to Common Lisp. Extensible sequences allow you to create your own sequence types that integrate with the rest of the functions and operations that interact with sequences.

Defstar is a collection of Common Lisp macros that can be used in place of defun, defmethod, defgeneric, defvar, defparameter, flet, labels, let* and lambda. Each macro has the same name as the form it replaces, with a star added at the end, e.g. defun. (the exception is the let* replacement, which is called *let).

This library is a small interface to portable but nonstandard introspection of Common Lisp environments. It is intended to allow a bit more compile-time introspection of environments in Common Lisp.

Quite a bit of information is available at the time a macro or compiler-macro runs; inlining info, type declarations, that sort of thing. This information is all standard - any Common Lisp program can (declare (integer x)) and such.

This info ought to be accessible through the standard &environment parameters, but it is not. Several implementations keep the information for their own purposes but do not make it available to user programs, because there is no standard mechanism to do so.

This library uses implementation-specific hooks to make information available to users. This is currently supported on SBCL, CCL, and CMUCL. Other implementations have implementations of the functions that do as much as they can and/or provide reasonable defaults.

CIEL is a ready-to-use collection of libraries providing: a binary, to run CIEL scripts; a simple full-featured REPL for the terminal; a Lisp library and a core image.

Montezuma is a text search engine library for Lisp based on the Ferret library for Ruby, which is itself based on the Lucene library for Java.