A16z-backed Iron Fish launches privacy-focused blockchain on mainnet

Quick Take

  • Iron Fish, a Layer 1 blockchain project, has launched its mainnet after a couple of years in development.
  • The blockchain has implemented zero-knowledge proofs, allowing users to transact privately without compromising accessibility.

Iron Fish, a Layer 1 blockchain initiative emphasizing transactional privacy through zero-knowledge proofs, has released its mainnet after being in development for more than two years. 

The Iron Fish team secured $28 million in a funding round led by Andreessen Horowitz in 2021. It's conducted three testnet phases spanning from 2022 to the first quarter of 2023 prior to the release. There seems to be significant interest in the Layer 1, which had over 60,000 nodes by the conclusion of its most recent testnet phase.

Iron Fish is wading into a crowded field of privacy-focused payment networks and blockchain protocols that includes zCash, Secret Network, Oasis, Aztec and Aleo.

The blockchain leverages, Zero-knowledge proofs (ZKPs), a cryptographic technique that allows one party  to prove to another party that they possess certain information or that a specific statement is true without revealing any details about the information itself. This technique can be used either to help blockchains scale or to achieve transactional privacy. In Iron Fish's case, it's the latter.

Iron Fish is a proof-of-work chain

Iron Fish is also based on a proof-of-work consensus mechanism, so users can operate specialized machines to mine the native cryptocurrency of the network. Despite the energy consumption associated with proof of work, this consensus has proven to provide security against network takeovers and data manipulation, as well as maintain decentralization.

"Iron Fish is a proof-of-work (PoW) based layer 1 blockchain network, intended to serve as a fully-compliant privacy layer for digital assets and web3," Elena Nadolinski, founder and CEO of Iron Fish, told The Block. "Using zero-knowledge proofs and robust encryption standards, Iron Fish enables users to transact in a fully private way, without compromising on accessibility."


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The team said it is aiming to carve out a niche in the privacy sphere by providing native mechanisms that potentially hold an edge over blockchains where user tracing is more straightforward. They do this by allowing users to execute anonymous and private transactions using zero-knowledge proofs.

Emphasis on interoperability 

Interoperability is another key aspect of Iron Fish, the team said, enabling users to bridge assets from other blockchains, including Bitcoin and Ethereum, to facilitate increased privacy in transactions for users.

One of the features we've worked hard on is this multi-asset feature—meaning that Iron Fish can now comprehend different assets, allowing a bridge operator to bridge assets across from other chains onto Iron Fish—making Iron Fish a privacy platform for such assets.

“We want to support transparent bridges that have programmability. So, for instance, you might want to move an asset from Ethereum over to Iron Fish. You have the programmability of Ethereum and then if you want the privacy, you move the assets over to Iron Fish to transact, store, and swap privately," Nadolinski added. 

© 2023 The Block. All Rights Reserved. This article is provided for informational purposes only. It is not offered or intended to be used as legal, tax, investment, financial, or other advice.

About Author

Vishal Chawla is The Block’s crypto ecosystems editor and has spent over six years covering tech protocols, cybersecurity, artificial intelligence and cloud computing. Vishal likes to delve deep into blockchain intricacies to ensure readers are well-informed about the continuously evolving crypto landscape. He is also a staunch advocate for rigorous security practices in the space. Before joining The Block, Vishal held positions at IDG ComputerWorld, CIO, and Crypto Briefing. He can be reached on Twitter at @vishal4c and via email at [email protected]


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