Blog | LF Decentralized Trust

Celebrating Web3j 5: A Journey from 2016 to Today

Today, we’re excited to announce the release of Web3j 5, a major milestone in a journey that began back in September 2016. What started as an open source project to make Ethereum accessible to Java and Android developers has now grown into one of the most widely used Java libraries in the blockchain ecosystem. And established itself as an important integration technology in the LF Decentralized Trust project landscape.

Over the years, Web3j has become more than just a tool. It's a community, a set of innovations, and a bridge between Ethereum and the Java ecosystem. Let’s take a look back at the challenges, achievements, and milestones that brought us here.

The Journey: Challenges and Growth

Building and maintaining a blockchain library is no small feat. Since 2016, we’ve faced the fast-paced evolution of Ethereum itself, protocol changes, new EIPs, shifting consensus mechanisms, and the growth of decentralized applications.

Key challenges included:

  • Keeping pace with Ethereum’s rapid protocol upgrades and EIP proposals.
  • Ensuring backward compatibility while introducing new features.
    Supporting a wide range of environments, from Android devices to enterprise systems with HSMs.
  • Building a developer experience that is intuitive for both beginners and advanced blockchain engineers.

Through it all, the Web3j community and contributors helped us stay focused, resolve issues, and push the project forward.

Milestones at a Glance

  • Created: September 2016
  • Accepted as a project by Hyperledger Foundation (and now part of the larger LF Decentralized Trust ecosystem): January 2024
  • GitHub Stars: 5.3k
  • Contributors: 218 unique contributors
  • Releases: 120
  • Forks: 1.8k
  • Issues Resolved: Over 1,000

These numbers reflect not only the growth of Web3j but also the strength of the open source community that powers it.

Key Features that Define Web3j

From the start, Web3j has been designed to make Ethereum development accessible in the Java ecosystem. Over time, we’ve expanded its feature set to keep pace with Ethereum’s evolution:

  • Complete implementation of Ethereum’s JSON-RPC client API (HTTP and IPC).
  • Ethereum wallet support.
  • Auto-generation of Java smart contract wrappers to deploy and interact with contracts from native Java code.
  • Transaction support: EIP-155, EIP-1559, EIP-2930, and EIP-4844 (the first Web3 library to do so).
  • Hardware Security Module (HSM) support for enterprise-grade security.
  • Android compatibility.
  • Ethereum Name Service (ENS) support.
  • Command-line tools for developers.

Staying Ahead: Support for Major EIPs

One of our biggest ongoing challenges has been supporting Ethereum’s constant evolution. Over the years, Web3j has kept pace with Ethereum Improvement Proposals (EIPs).

Here are some of the most important:

  • EIP-155: Chain ID protection for replay attacks.
  • EIP-1559: Base fee and gas fee improvements.
  • EIP-2930: Access list transactions.
  • EIP-4844: Proto-danksharding (supported first by Web3j).
  • EIP-4337: Account abstraction support.

This commitment to staying up to date ensures developers can always rely on Web3j to build on the latest Ethereum standards.

What’s New in Web3j 5

With the 5.0.1 release, Web3j is built for the future of Java and EVM development:

  • Enhanced Smart Contract Java Wrappers with Generated metadata
  • EIP-4337: Account abstraction support
  • EIP-7702: EOA enhancements
  • A series of improvements and bug fixes

This release represents not just stability and modernization but also a commitment to longevity ensuring Web3j remains a dependable foundation for Ethereum development in Java for years to come.

Community and Mentorship

The progress of Web3j has always been shaped by both its very active project and the global LF Decentralized Trust communities. Along the way, the mentorship programs from LF Decentralized Trust provided valuable guidance that helped us overcome key challenges and grow as a project.

The mentorships that made a real impact include:

Equally important has been the dedication of active contributors from the open source community. Their continuous support, whether through code contributions, issue reporting, or reviews, has been instrumental in keeping Web3j reliable, relevant, and forward looking.

The success of Web3j is as much about this collective effort as it is about the core development team at Web3Labs.

Looking Ahead

From its humble beginnings in 2016 to becoming a library with millions of downloads and hundreds of contributors, Web3j has grown alongside Ethereum itself.

The release of Web3j 5 is both a celebration of what we’ve accomplished and a reminder of what lies ahead. As Ethereum continues to evolve, Web3j will remain committed to empowering developers, supporting innovation, and bridging the gap between blockchain and the Java ecosystem.

Thank you to every contributor, user, and supporter who has been part of this journey. Here’s to the next chapter of Web3j.

If you are interested in contributing to Web3j’s ongoing development, feel free to check out our GitHub repository and join the discussions! You can also find us here on the LF Decentralized Trust Discord.