Pharo GSOC 2018
Ideas List

Pharo is a pure object-oriented programming language and a powerful environment, focused on simplicity and immediate feedback (think IDE and OS rolled into one).

Table of Contents


Information for Students

These ideas were contributed by our developers and users. They are sometimes vague or incomplete. If you wish to submit a proposal based on these ideas, you may wish to contact the developers and find out more about the particular suggestion you're looking at.

Being accepted as a Google Summer of Code student is quite competitive. Accepted students typically have thoroughly researched the technologies of their proposed project and have been in frequent contact with potential mentors. Simply copying and pasting an idea here will not work. On the other hand, creating a completely new idea without first consulting potential mentors is unlikely to work out.

If there is no specific contact given you can ask questions on the general Pharo development list See the Pharo community page for information on available mailing lists and how to subscribe.

Adding a Proposal

Please propose your own project by following the following template. You can edit the list on github here: and send a pull request.

     PharoTopic new
       title: 'The name of your project';
       contact: 'email address';
       supervisors: 'Supervisors names';
       keywords: 'keywords separated by spaces';
       context: 'a description of the context of the project';
       goal: 'description of the goal';
       level: 'Beginner or Intermediate or Advanced';


Do not hesitate to ask questions. Administrators of this year’s application are Serge Stinckwich, Alexandre Bergel, Jigyasa Grover, Yuriy Tymchuk.

Pharo GSOC Topics

Supervisors Philippe Back
KeywordsHadoop Cluster Distributed computing Big data REST Kerberos GSSAPI Polymath Zookeeper
ContextPharoya stands for Pharo on YARN. YARN, the underlying system under Hadoop, allows one to write distributed applications running in YARN containers on (lots of) compute nodes. This project is meant to run Pharo instances on such containers and report back to the Pharo Application Manager. Integration with Polymath is desirable. This project will be able to run run on a 1200+ core/4TB RAM/50TB Storage system. Pharo images are smaller than Java UberJars and will use less cluster resources for more results.
GoalMake Pharo a first class citizen on Hadoop clusters as a YARN application
LevelIntermediate to Advanced
CandidateTopic still free

TitlePharo Launcher command line interface
Supervisors Guillermo Polito, Christophe Demarey
Keywordsimage management, command line interface, virtualization
ContextThe pharo launcher is an application that allows the management of pharo images. In a "docker style", you can download images from templates, install them, list your installed images, and launch them. All this is done through a visual user interface in a desktop application.
GoalThe goal of this project is to implement a command line interface for the Pharo launcher, to be able to manipulate it on servers as we do with docker. For example: $ phlauncher list $ phlauncher templates $ phlauncher install X $ phlauncher run X
CandidateTopic still free

TitleFinder 2.0: Reimplementing Example Based Query
Keywordsexample finder
Context Pharo comes with a super nice tools: the finder. The finder les you gives objects i.e. 11 .2 .5, meaning what is the message that sent to 11 with 2 as argument will return 5.
GoalThe goal of this project is to revisit completely the design of the tool. In particular we should not use global tables but each class should be able to declare the methods that can be found or not this way. In addition adding tests and rethinking the core functionality is part of the project. The project will have an impact on all the pharoers because this tool is super cool but needs some love.
CandidateTopic still free

TitleDistributed Issue Tracker
Supervisors Stephan Eggermont, Diego Lont
KeywordsP2P Tools GUI
Context Most development in Smalltalk uses distributed version control systems, either Monticello or Git. But the current issue tracker is web-based and cannot work disconnected. Integrating the issue tracker in the CI workflow of the projects is crucial. There is a small prototype available. **Benefits to the Student getting to know the difficulties of issue tracking/the workflow of open source projects; experience with distributed systems; experience an agile open source environment; **Benefits to the Community bring new developers into the community better integrated workflow; native issue tracker, accessible both in-image, web and automated
GoalA native smalltalk distributed issue tracker. It should have basic issue tracking functionality including attaching files/pictures/code. It should have a native interface, a web interface and a scripting API. Primary development is in Pharo.
CandidateTopic still free

Supervisors Oleksandr Zaytsev, Serge Stinckwich
Keywordsdata science, data analysis, dataframe, tabular data, statistics
ContextDataFrame was introduced to Pharo during the previous GSoC ( The work on DataFrame continued and many new features were introduced by different contributors. However, it is still a work in progress and a huge portion of functionality that can be found in other data frame packages (e.g. R, pandas) is missing.
GoalThe goal of this project is to introduce new functionality to DataFrame (for example, handling missing values) and write examples of applying DataFrame to real problems of Data Science (one can reproduce examples from pandas and scikit-learn documentation, as well as some examples from R-bloggers)
CandidateTopic still free

TitleIPFS for Pharo
Keywordspeer to peer file systems
Context IPFS is a peer-to-peer distributed file system that seeks to connect all computing devices with the same system of files. In some ways, IPFS is similar to the Web, but IPFS could be seen as a single BitTorrent swarm, exchanging objects within one Git repository. In other words, IPFS provides a high throughput content-addressed block storage model, with content-addressed hyperlinks. This forms a generalized Merkle DAG, a data structure upon which one can build versioned file systems, blockchains, and even a Permanent Web. IPFS combines a distributed hashtable, an incentivized block exchange, and a self-certifying namespace. IPFS has no single point of failure, and nodes do not need to trust each other. IPFS right now is implemented as a server process in Go and allows the global file system to be mounted as a user space filesystem. In addition, the server provides an API. A real integration of IPFS with Pharo would require a complete implementation of IPFS in Pharo (projects are already in early stages to implement it in JavaScript and Python). But the client API allows us already now to do experiments and assess the usefulness of IPFS in the context of Pharo. More information:
GoalThe goal of this Project is to implement a IPFS client library using the API to communicate with the existing server and start to experiment how IPFS can be used with Pharo. For example, extend the launcher to load images via IPFS, distribute the files of smalltalkhub or provide access to resources via IPFS.
CandidateTopic still free

TitleImproving code completion
Supervisors S. Ducasse, E. Lorenzano and Juan Pablo Sandoval A.
ContextAutomatic completion is really important. The current code completion already defines some good behavior but it can do better.
GoalThe goal of the project is to improve the ecompletion infrastructure: The tasks are: (1) study the existing approaches (NOC and NEC), (2) Write some tests to characterize specific behavior, (3) Improve the noise introduced by the Symbol table usage, (4) build more heuristics.
CandidateTopic still free

TitleMaterial Design Lite
Supervisors Cyril Ferlicot-Delbecque
Keywordsmaterial design lite, material-ui, seaside, web, components
ContextMateria Design Lite ( is a set of web components for the Seaside framework based on Google's Material Design guidelines.
GoalThe goal of this project is to create new components, use these components to create more complexe components and potentialy add tests to the existing components.
LevelBeginner to Intermediate
CandidateTopic still free

TitleHacking Pharo in Your Web Browser and
Supervisors Luc Fabresse and Damien Pollet
KeywordsDocker, Virtual machine
ContextThere is a need to be able to execute Pharo code through a web page. It implies sending code to the server-side for execution. However this execution should not expose the file system and machine resources. The idea of this problem is to run Pharo in a container and expose it in a web application. Such an isolated infrastructure could be useful for experimenting with Pharo trhough a Web page.
GoalPossible tasks are: - Have a look at / / - Learn Docker - Make a first version - Build a little webfront end.
CandidateTopic still free

TitleTwo-way synchronized code changes, better support for cross-platform co-development
Supervisors Stephan Eggermont, Diego Lont
ContextGlorp is originally maintained in VisualWorks. We now have a version in Pharo that is forked. It would be nice if we could make sure that changes can be synchronized. The rewriting engine is available on both platforms, and Glorp has a large number of unit tests. If we can describe both migrations with refactorings, we should be able to create builds in ci for both that show when changes break things and otherwise synchronize two-way. This might also be beneficial for Roassal2 and Seaside, that currently use a compatibility layer. Another place where this rewriting can be useful would be in maintaining compatibility between Squeak and Pharo, and in making it easier keeping older code alive. Marcel Taeumel has written a number of interesting applications (UIBuilder, Widgets, XPForums) using a 'signals' style communication. In Pharo it would make sense to have them use Announcements.
GoalTwo-way synchronized code changes, 1st target: GLORP
CandidateTopic still free

TitleBetter and more refactorings for Pharo
Supervisors Anyone
KeywordsRefactoring IDE
ContextSmalltalk was the first environment to have such great refactorings that inspired a lot of languages and book authors. Unfortunately, refactoring support lowered in quality and some of them are now missing in Pharo.
GoalThe goal of this project is to provide Pharo developers a good refactoring support, comparable to modern IDEs like IDEA Intellij. See for a detailed list of tasks.
CandidateTopic still free

TitlefreeCAD: 3D CAD with Motion Simulation
Supervisors Aik-Siong Koh
KeywordsMotion Simulation Multibody Dynamics
ContextfreeCAD is a basic 3D CAD with advanced Motion Simulation capabilities. Originally written in VisualWorks Smalltalk, a port to Pharo will make it completely open source for a greater audience. Its motion simulation capabilities are comparable to the best and can provide accurate answers to engineers and scientists in diverse fields. Educators, students and new engineers will find it ideal for the teaching and learning of geometry, kinematics, dynamics, vibrations, mechanisms, linkages, cams, machine design and physics.
GoalTo use the power of Pharo to create a killer Computer Aided Design and Engineering tool for all
CandidateTopic still free

TitleTaking Advantage of Immutable Objects
Supervisors C. Bera
KeywordsWrite barrier
ContextPharo since its version 60 supports object immutability primitives at the Virtual Machine level as explained here It means that once marked as immutable objects cannot be modified and raise an error. For deep Virtual machine optimisations that fold stack elements, having strings as immutable objects is key. Now the core Pharo libraries may still use some mutable strings. Therefore the core libraries of Pharo should be revisited to identify use of mutable structures. Now we face several challenges: - Identification of part thats can be migrated to immutable objects. - Identification of patterns of potential problems. In addition, there is a need to propose to the Pharo developers a way to take advantage of immutability. A typical example is the use of write barrier (to identify objects that changes and therefore should be committed to database). We need to explore the design of a frameworks to let the developer expresses what should be done when an immutable object detects an attempt to modify it.
GoalTasks: Here is a possible outline of work: The student will - study current Pharo libraries for use of literal objects such as strings - define solution to avoid the use of mutable objects (in particular strings) - present the results to the core development team - iterate and help integrating the good results :) - start designing a first write barrier frameworks Resources: -
CandidateTopic still free

TitleKeras for Pharo
Supervisors Alexandre Bergel
KeywordsArtificial Intelligence
Contexta description of the context of the project
GoalThe goal of this project is implement the necessary in Pharo to be able to access the main functionalities of Keras. The first phase of the effort is to use Python3Generator to interact with Python. The second phase is to wrap a representative set of Keras functionalities. As a third phase, is to design a set of compeling examples.
CandidateTopic still free

TitleLiberated Pixel Cup native support in Pharo
Supervisors Clement Bera, Stephane Ducasse ?
KeywordsCairo SDL 2D
ContextIt is now possible to build quite good 2D native applications in Pharo using Cairo and SDL, which led to experimental video games (article in Linux Mag of April 2018, On the other hand, projects such as The Liberated Pixel Cup supported by the Mozzila Foundation and other large groups develop huge graphic ressources available under open source licenses ( Note the student is strongly advised to use a Linux machine for this work.
GoalThe first goal is to create a library to easily import and display LPC characters generated from website like this one ( into the Pharo stack (SDL, Cairo & Pharo). Second goal is to build a minimal video game framework on top of it with a game. Lastly, the third goal is to improve packaging & deployment of such native applications in Pharo, as well as evaluating the integration with other frameworks (Bloc to display GUI for example). The third goal has to be clearly detailled in the student proposal - we will not accept topics not improving the Core Pharo system. In addition, the demo game created should be submitted to this year LPC event (competition from June 1st to July 31st) to show Pharo to other communities.
LevelBeginner to Intermediate
CandidateTopic still free

TitleNew Collections for Pharo
EmailJuan Pablo Sandoval Alcocer <>
Supervisors Juan Pablo Sandoval Alcocer
KeywordsCollection DataStructure Benchmarks
ContextPharo contains a large set of collections (See PharoByExample Collections chapter) with around 100 classes. But new collections exist such as BTree, QuadTree, SkipList, Trie, … Containers is an existing effort to gather many of the existing collection developed individually and externally to Pharo into a single umbrella. The idea is to create a modular collection library for Pharo users. Containers’s goals is to develop new efficient, well-tested, well documented collections. Containers contains already Tree, Grid, SkipList, LinkedList, OrderedDictionary but there is a need to revisit them. Finally Pharo 6.0 comes with two powerful primitives: new object immutability primitives as well as ephemerons [Hayes97]. With such important primitives two tasks can be performed: - design new weak collections taking advantage of ephemerons. - revisit and design new concurrent collections taking advantage of immutability. Links: - Camillo Bruni master contains a chapter on how to benchmark for collections - started to implement some new collections for Pharo. -
GoalTasks: - The student will study current Collections of Pharo (See PharoByExample Collections chapter) for an overview. - He will study the new collections in the project named Containers on Smalltalkhub.!/~StephaneDucasse/Containers - Migrate some existing projects to Containers (adding tests, comments). - Design and implement new collections such as -- BTree, QuadTrees, -- Immutable list, set, array Resources: - Camillo Bruni master contains a chapter on how to benchmark for collections - started to implement some new collections for Pharo. - - Barry Hayes, Proceedings OOPSLA '97, ACM SIGPLAN Notices, Ephemerons: A new finalization mechanism, 1997
CandidateTopic still free

TitleMQTT support for Pharo,
Supervisors Sven Van Caekenberghe, Juraj Kubelka
Keywordsmqtt, internet, protocol, client
ContextMQTT is a proven ISO standard machine-to-machine (M2M)/"Internet of Things" connectivity protocol. It was designed as an extremely lightweight publish/subscribe messaging transport. It is useful for connections with remote locations where a small code footprint is required and/or network bandwidth is at a premium. See for more details or "Using MQTT in Real-World M2M Communication” talk that explains MQTT protocol and covers common scenarios: Pharo project already supports MQTT protocol ( including clients and use cases ( or
GoalThe goal of this project is to improve existing code (MQTT, callback client, chat). Namely add more test cases in order to cover common scenarios, improve documentation, and add support for large files inspired by the talk mentioned above.
CandidateTopic still free

TitleEnhancing Pillar
Supervisors Stéphane Ducasse
KeywordsPillar OpenDocument LibreOffice OpenOffice document tree visitor
ContextPillar is a markup syntax that is easy to use and learn. This markup syntax generates a document tree. P illar can export to HTML, LaTeX (to produce PDFs) and Markdown. Pillar has already been used in several projects (!/~Pier/Pillar) and most of the pharo books and mooc
GoalThe goal of the project is to do help in the development of the new iteration of Pillar. Previous development effort introduced a better architecture but there are still some points to improve. - Documenting certain classes - Improving the archetype design - Separating command-line into object configurators and command-line - Producing a new version of ectastic that uses the lastest version of pillar. - One subgoal of this project is to add the standard OpenDocument export format (used by LibreOffice and OpenDocument).

TitleWeather/Meteo for OpenStreetMap in Roassal
Supervisors O. Goubier
KeywordsGrib, OpenStreetMaps, Roassal
Context With Roassal and OpenStreetMap, it is possible to explore geo-referenced data sets and easily script complex, interactive, geo-referenced visualisations. Now, there is a lot of external data sources to use and integrate with Roassal!
Goal The goal of this project is to add a support for importing Grib data sets ( in Roassal. Those datasets give access to weather information and predictions from many sources, and we need a support to import such files into Pharo and Roassal
CandidateTopic still free

TitleNext Generation Unit Testing
Supervisors Guillermo Polito
Keywordsunit testing, parallelization, configuration
ContextSUnit is the current unit testing framework in Pharo. Building complex applications require new testing capabilities, with an enhanced UI and a clear API that allows new extensions.
GoalThe goal of this project is to redesign the SUnit framework to be extensible. The extension points and hooks in the framework should allow users to create their own extensions. Moreover, the student will implement extensions for common testing scenarios such as concurrency and parameterized tests.
CandidateTopic still free

TitleJupyter Support for Pharo ,
Supervisors Serge Stinckwich, Nick Papoulias
KeywordsLive coding, UI, Notebook, Interoperability, Literate Programming
ContextJupyter is a web notebook that supports an interactive form of literate programming. It is written in python but other languages can be integrated to its workflow through custom "jupyter kernels". The goal of this project will be to integrate Pharo with Jupyter allowing easy experimentation, exploration and documentation of Pharo examples (for Roassal, Polymath etc) on the web.
GoalAdd Pharo support for Jupyter
CandidateTopic still free

TitleVector instructions in Pharo
Supervisors Clement Bera
KeywordsAVX MMX vector
ContextOn the one hand, recent work has allowed the Pharo bytecode set to be extended relatively easily to use more low-level operations. On the other hand, the Sci Smalltalk community is developping on top of Pharo and the Maths/Matrix librares would greatly benefit from native vector instruction usage.
GoalGoing bottoms up, the student would need first to implement support for AVX-256 x64 double-floating pointer instructions in the compiler back-end, with tests showing that they actually work. Second, he needs to leverage these instructions to the bytecode level designing a small DSL with a micro-compiler compiling from the DSL to bytecode. Lastly, he needs to build a small Matrix or Maths libraries using those instructions and evaluate the performance.
CandidateTopic still free

TitleZeppelin Support for Pharo
Supervisors Philippe Back
KeywordsLive coding, UI, Notebook, Interoperability, Literate Programming, Integration, Polyglot programming
ContextZeppelin is a Web-based notebook that enables data-driven, interactive data analytics and collaborative documents. Zeppelin Server is in Java and Interpreters are using some way to connect to other languages for notebook paragraphs (network socket, library, ...). The goal of this project is to integrate Pharo with Zeppelin and delivering initial examples in Pharo.
GoalAdd a Pharo Zeppelin Interpreter to Zeppelin
CandidateTopic still free

TitleGRASS integration with Pharo/Roassal
Supervisors O. Goubier
KeywordsGIS, GRASS, Roassal
Context With Roassal and OpenStreetMap, it is possible to explore geo-referenced data sets and easily script complex, interactive, geo-referenced visualisations. Now, there is a lot of external data sources to use and integrate with Roassal!
Goal The goal of this project is to integrate GRASS ( with Pharo. GRASS provides an extensive set of advanced GIS functions (modeling, simulations, data import, projections, etc...) and should be integrated inside Pharo, first as a set of external commands (with a Pharo-based GUI front-end), and maybe as a FFI interface.
CandidateTopic still free