phratch is a visual programming language based on a jigsaw puzzle on top of Pharo. More than just an overlay, the goal of phratch is to bring closer the visual blocks and the Smalltalk language. Phratch is highly extensible, which makes it easy to implement new blocks and new features. The main goal of phratch is to become a robotics development environment for non-expert. It already works on top of the Lego Mindstorms and on the Robosoft Kompai.

It is a port of Scratch ( on a recent platforms (Pharo 3.0). It is the evolution of the Scat project ( which provided a port of Scratch on Pharo 1.3. Thanks to the developers of Scat, phratch has strongly evolved to become a really cool tool.

More than Scratch, phratch includes BYOB, Build your own Blocks ( It allows one to create a block composed by other blocks. Creating a block is available in the category variables below the creation of variable and creation of list. Then, It is possible to edit the block by right clicking.
phratch is also Panther: It includes two interesting categories: Files and colors. Files allows one to manipulate local and remote files, and Colors to manipulate color features.

phratch includes new features like Settings, FileSystem, Metacello. For example, we can edit a normal block, and a real code browser is opened.

A block is a smalltalk method containing a pragma. This pragma informs phratch that this method should be displayed as a block. A lot of Blocks are provided by default: from Scratch but also a lots of them comes from BYOB, and Panther.

You can find phratch and tutorials on this website.

phratch ESUG 2013, 10th Innovation Technology Awards Submission from jannik Laval on Vimeo.

phratch to control Mindstorms from jannik Laval on Vimeo.

To ask question or discuss with developers or contribute, you can use the following ways:

  • First of all, you can download it and try it. If you have any problem or bug, you can add an issue in the bug tracker.
  • Then, if you are a Smalltalk developer, you can easily contribute to fix these bugs.
  • Another way to contribute is to make documentation for phratch. Some posts are already available on this website.
  • You can also extend phratch with your own blocks. Do not hesitate to share with us your productions.

To download the latest version of phratch, just follow the instructions.

phratch won the 3rd place of the ESUG “Innovation Technology Awards” at Annecy 2013.


phratch website is sponsored by ESUG