Hyperledger

Hyperledger is an umbrella of open-source blockchain projects hosted by the Linux Foundation, best known for Hyperledger Fabric, a framework for private business ledgers, and Besu, an Ethereum client used on both public and permissioned networks. The Linux Foundation announced the Hyperledger Project in December 2015 and named its founding members, among them IBM, Intel, J.P. Morgan and Accenture, in early 2016. The initiative later operated as Hyperledger Foundation.

Hyperledger is not a single blockchain and has no coin. It is a collection of software that companies, governments and consortia use to build their own networks, usually a Permissioned Blockchain in which only approved organisations run nodes. In September 2024 its projects moved into a broader body, Linux Foundation Decentralized Trust (LF Decentralized Trust), and some, including Besu, now go by their own names without the Hyperledger prefix.

Think of a public library that hands out free building plans. The library does not build houses itself. It collects good designs, lets anyone use them, and gathers volunteers from many firms who keep improving the plans. A bank, a shipping company or a government office can take a plan and build its own house, and invite only the neighbours it trusts.

Hyperledger is that library for business blockchains. Instead of joining a public network open to anyone, a group of companies can use Hyperledger software to set up a shared record that only its members can write to. Everyone keeps a matching copy, so no single member can quietly change past entries, but outsiders are kept out.

Hyperledger emerged during the 2015–2016 wave of corporate interest in Distributed Ledger Technology (DLT), when banks and technology firms wanted the record-keeping benefits of a Blockchain without public tokens, anonymous participants or mining. Brian Behlendorf, an early Apache web-server developer, became its executive director in 2016.

Code was contributed by members: IBM's work became Fabric, Intel contributed Sawtooth, and other teams added identity, interoperability and tooling projects. Fabric 1.0, the first production-ready release, appeared in July 2017. In 2019 ConsenSys contributed its Pantheon Ethereum client, renamed Hyperledger Besu, bringing Ethereum Blockchain compatibility into the family. The September 2024 launch of LF Decentralized Trust placed the Hyperledger projects alongside other digital-trust efforts, including the Hiero project built from code contributed by Hedera.

• Fabric. A modular framework for private networks. Members are identified by certificates, data can be split into "channels" visible only to certain parties, and business logic runs as "chaincode", Fabric's term for a Smart Contract (SC), written in general-purpose languages such as Go or JavaScript.
• Besu. An Ethereum client written in Java that runs on the public Ethereum network and in private deployments. It executes code in the Ethereum Virtual Machine (EVM), so contracts written in Solidity work unchanged.
• Identity projects (Indy, Aries and related work). Tools for decentralised identity and verifiable credentials.
• Cacti and FireFly. Tooling for Blockchain Interoperability and for building applications that connect to several ledgers.

Several earlier projects, such as Sawtooth and Burrow, have been archived as activity shifted to Fabric and Besu.

On a Permissionless Blockchain such as Bitcoin, anyone can run a Node (Blockchain) and agreement comes from economic security such as Proof of Stake (PoS). Hyperledger networks instead rely on known participants. Fabric separates the work into steps: selected peers execute and endorse a transaction, an ordering service puts transactions in sequence (commonly using the Raft protocol), and peers validate and commit them. Besu private networks can use voting-based Consensus algorithms in the family of Practical Byzantine Fault Tolerance (PBFT), in which a set of named Validators agree on each block. The result is faster finality and privacy controls, at the cost of decentralisation: the members can, together, change the rules.

Hyperledger software has been used in trade-finance platforms, supply-chain tracking, digital identity and central-bank experiments. IBM built its enterprise blockchain services on Fabric, including food-traceability and shipping networks. In 2023 Brazil's central bank chose Besu for the pilot of Drex, its digital-currency and Tokenization platform, one of several Central Bank Digital Currency (CBDC) trials on Ethereum-compatible permissioned technology; the bank later reported that the privacy solutions tested had not met its requirements. Common use cases overlap with those listed in Top 20 Use Cases where Blockchain can be used.

• Is it a blockchain at all? Critics argue a ledger run by a few known firms is closer to a shared database or Private Ledger, and that its benefits could often be achieved more simply.
• Consortium failures. Several high-profile Fabric-based networks, such as the TradeLens shipping platform, closed after failing to sign up enough industry participants.
• Complexity. Running certificate authorities, ordering services and upgrades across many organisations is demanding.
• Drift towards public chains. Since about 2020 much enterprise interest has moved to Ethereum-Compatible Blockchains, a trend also visible in the work of the Enterprise Ethereum Alliance (EEA); Besu benefited, Fabric less so.

• Linux Foundation Decentralized Trust
• Hyperledger Fabric
• Besu