Pier is a free

Free software

Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...

 and open source content management system

Content management system

A content management system is a system providing a collection of procedures used to manage work flow in a collaborative environment. These procedures can be manual or computer-based...

 written in Smalltalk

Smalltalk

Smalltalk is an object-oriented, dynamically typed, reflective programming language. Smalltalk was created as the language to underpin the "new world" of computing exemplified by "human–computer symbiosis." It was designed and created in part for educational use, more so for constructionist...

 using the Seaside web application framework.

Pier is written with objects from top to bottom. Pier is based on Magritte, a meta-description framework. It has shown itself to be very powerful together with the Seaside framework, to enable composing and configuring interactive web sites through a convenient web interface without having to write code. Pier provides an extensive list of ready-made plugins.

Ports

The main development of Pier happens in Pharo

Pharo

Pharo is a fork of Squeak, an implementation of the object-oriented, dynamically typed, reflective programming language Smalltalk.Appearing in 2008, Pharo focuses on removing unessential code from Squeak and serves as the reference implementation of Seaside, a web application framework for...

. There are ports to other Smalltalk dialects such as VisualWorks

VisualWorks

VisualWorks is a cross-platform implementation of the Smalltalk language. It is implemented as a development system based on "images", which are dynamic collections of software objects, each contained in a system image....

 and Gemstone/S

Gemstone Database Management System

GemStone is a proprietary application framework that was first available for Smalltalk as an object database.GemStone Systems was founded in 1982 as Servio Logic, and then became GemStone Systems, Inc in 1995. GemStone developed its first prototype in 1982, and shipped its first product in 1986. ...

.