Libraries & Tools



RSKj is the JavaScript Library within the RSK Foundation. Work is mainly done within the following GitHub organization:

There are currently over 20 active repositories, most (with some exceptions like keythereum <>_ or
ethrpc <>) managed by the EF team. Some central libraries are an implementation of the Ethereum Virtual Machine <>, our Client <>_ project and implementations of the Merkle Patricia Tree <>_ data structure or the devp2p <>_ networking stack.

Have a look at the overview page linked above to get an impression what is currently being worked on as well as other libraries available.

Focus and related Projects

Main focus of EthereumJS is to provide high-quality and robust implementations of core Ethereum infrastructure technologies (virtual machine), protocols (devp2p) and data structures (merkle tree).

Other related projects you might want to check out as well are e.g.:

  • web3.js <>_ (Ethereum JavaScript API)
  • ethers.js <>_ (Ethereum Wallet implementation and library)
  • Truffle <>_ (Development Framework)
  • embark <>_ (dApp Framework)
  • Remix <>_ (

Most of the projects above also make use of some of our base-layer libraries. EthereumJS libraries are also used by various other actors within the ecosystem like MetaMask, 0x or Augur.

.. _contact:

Team and Contact

EthereumJS is a strongly community-driven project and the active team is regarded as the sum of people actively contributing to the libraries. Some people are also hired by the Ethereum Foundation to provide a somewhat more solid ground on ongoing development and having people with in-depth knowledge as steady contact persons for the libraries.

For technical questions as well as getting in touch you can use our Gitter channel:


Organizational questions are centered and discussed on the organization repo:


.. _ongoing_work_tasks:

Ongoing Work Tasks

The following is an overview on ongoing work tasks to get an idea on the current focus of work. This is also serving internal accounting purposes.

.. note:: This list is focussing on reoccuring work tasks, for an overview on dedicated new projects have a look at the :ref:roadmap section.

W1 - Virtual Machine Development

One strong emphasis of EthereumJS work is on maintaining and further developing a robust and up-to-date JavaScript virtual machine implementation (ethereumjs-vm <>_).

Main tasks around this are:

  • Updating the VM on new hardforks
  • Targeting compliance with the latest consensus test suite <>_ releases
  • Implementing feature requests from the community (Truffle, Remix, others), e.g. to provide better debugging functionalities
  • Ongoing refactoring work to open up new use cases

W2 - Library Modernization

EthereumJS libraries provide robust and solid implementations surving the dedicated purposes, but code and API on many libraries lacks a bit behind regarding modern, well-to-read and easy to use JavaScript features.

There is an ongoing effort to modernize the libraries, this nevertheless takes time to not introduce new bugs or break existing APIs.

Currently there is a focus on (you are very much invited to help :-)):

  • Using ES6 classes for structuring library components
  • JavaScript Promise based interfaces (in contrast to callback logic)
  • Updating on security improving language features (block-scoped variables,…)
  • Improving on code readability (destructuring of objects,…)

.. note:: Complementary to this work is the task of establishing a robust transpilation process with tools like babel and others to make sure that our libraries are usable in environments where modern JS language features are not yet available

W3 - Bug Fixes and Maintenance

EthereumJS libraries are widely used in production - often in security-sensitive contexts - and there is an ongoing effort to keep libraries up-to-date and secure.

Main tasks around this:

  • Fix bugs reported by the community in a timely fashion
  • Keep library dependencies up-to-date
  • Adopt libraries to various user work environments and build pipelines (browser, React,…)
  • Be responsive to feature requests from the community

W4 - Testing and CI

To provide a high level of reliable we target a high test coverage on all of our libraries and writing new tests and integrate these in the everyday work process (CI) is an ongoing effort.

Efforts include:

  • Improve test coverage for library APIs
  • Add and maintain integration tests (with a focus on browser testing)
  • Integrate test runs / coverage reports into CI process
  • Benchmark libraries, performance improvements for both library execution and tests

W5 - Community Work

There is a high level of engagement from the community with the different EthereumJS libraries and there are countless examples for both evolutionary updates as well as high-quality and broadly scoped feature contributions from the community.

We are determined to put substantial ressources here to further support exchange with and engagement from the community.

Related tasks are:

  • Help onboard new contributors, give introductory guidance
  • Review of Pull Requests
  • Accompany community development work
  • Management and structuring of issues and PRs
  • Responsiveness on communication channels

W6 - Accessibility

Very much related to the community efforts (W5) is the goal of making libraries generally as easily approachable as possible and so to lower the barrier to engage and minimize the need to to do one-to-one explanations on how things work.

Tasks include:

  • Provide up-to-date and consistent API documentation
  • Instructions on environment setup and installation, developer docs
  • Easy to recreate and up-to-date examples in README
  • Common standards and standard documentation (these docs :-)) whenever possible
  • Easy to understand, modular and documented source code