Contribute to Squeak

Development Process

The Squeak Development Process supports the improvement of Squeak—the core of the system and its supporting libraries—by its community. The process builds on few basic ideas: the use of Monticello as the primary source code management system, free access for the developers to the main repositories, and an incremental update process for both developers and users. (Read More)

Squeak Bug Tracker

If you identify an issue in Squeak, please file a bug report here. Squeak core developers regularly check the bug repository and will try to address all problem as quickly as possible. If you have troubles posting there, you can always post the issue on our development list.

Develop Your Own Applications


A Monticello code repository for Squeak. Many of our community’s projects are hosted here. Others you may find at SqueakMap or the now retired SqueakSource1.

Version Control with Git

Using the Git Browser, you can commit and browse your code and changes in Git and work on projects hosted on platforms like GitHub. With Monticello you can read and write FileTree and Tonel formatted repositories in any file-based version control system.

Continuous Integration

Travis CI is a continuous integration service that you can use to build and test your projects on GitHub. Since Squeak/Smalltalk is a supported language on Travis CI, it is easy to activate testing for your projects using the smalltalkCI framework.

SqueakSource Server

Learn how to setup your own Monticello code repository server. (Read More)

Virtual Machines

OpenSmalltalk VM

A family of virtual machines that supports Smalltalk and other languages of the Smalltalk family, including the standard VM for Squeak, Pharo and Newspeak. Just-in-time compilation, stack-to-register mapping, and aggressive in-line message caching yield efficiency in executing Smalltalk byte code. Being a fork of VMMaker, OpenSmalltalk VMs provide safe incremental development of JIT VMs.

Classic VM

The classic Squeak VM is implemented and developed in Slang, a subset of Squeak/Smalltalk which can be translated into C. The VM can be built using VMMaker.

SqueakJS VM

An experimental virtual machine written entirely in JavaScript.


An experimental Squeak/Smalltalk VM and Polyglot Programming Environment for the GraalVM. It is written in Java using the Truffle language implementation framework.


An experimental virtual machine written in RPython and based on PyPy’s meta-tracing JIT Compiler infrastructure.


A manycore virtual machine which supports the parallel execution of Squeak programs on x86 compatible multicore machines and Tilera TILE64-based manycore systems.

Build Your Own VM

VMMaker allows any programmer to develop a customized virtual machine for any platform. VMMaker comprises the VM simulator that is used to develop the VM using the full power of the IDE, and a Smalltalk-to-C or Smalltalk-to-JavaScript translator that produces the sources for the production VM.


Codespeed tracks the performance of various Squeak virtual machines for comparison and development purposes.