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What is the ThunderCore Iris Hard Fork? by@thundercore

What is the ThunderCore Iris Hard Fork?

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ThunderCore is a secure, fast, EVM-compatible public blockchain for launching and scaling decentralized applications.

Introducing ThunderCore Iris, the next iteration of the ThunderCore blockchain! The Iris hard fork will go live on Mainnet at block height 82312803.

The goal of this major network upgrade is to bring the latest EVM Istanbul features to ThunderCore and further lower the barrier of porting Solidity projects into the ThunderCore ecosystem. 

Iris complements the performance and security upgrade introduced in the Soter hard fork in December 2020. With the introduction of the Iris hard fork, ThunderCore will become one of the fastest, most secure, EVM-compatible, cross-chain ready, and developer-friendly public blockchains in the industry!

In this blog post, we will share the important features of Mainnet Iris, and how they will impact ThunderCore developers and users.

Why Iris?

You may wonder, why Iris? If you’re a fan of Greek mythology, you may find our hard fork names very familiar. Back when we implemented the Soter hard fork, our goal was to increase the security of the ThunderCore blockchain, hence the name Soter, which, in Greek mythology, means ​​the male spirit of safety, preservation, and deliverance from harm.

Iris is the Greek goddess of communication, messages, the rainbow, and new endeavors. Being represented as a rainbow or as a beautiful young maiden with wings on her shoulders, Iris is the perfect symbol that personifies our incoming hard fork, as the Iris hard fork is meant to bring better cross-chain interoperability to the ThunderCore blockchain, creating a more developer-friendly platform for great projects to scale. Here’s to a new chapter of growth, development, and new beginnings.

Important note: When Iris is being implemented, certain exchanges will halt trading activities and/or deposit and withdrawal features for a certain period of time. Rest assured, they will resume shortly after. Please refer to each exchange’s announcement for more details.

Roadmap - What Does It Mean for Developers?

The Iris hard fork will be introduced with a phased rollout:

Phase 1: Estimated Date — 10/12, Block Height — 82312803

During Phase 1 of the Iris hard fork, the goal is to introduce a limited set of changes to ensure the stability of the Phase 2 rollout. The upgrades include:

1. Move consensus info from consensus transaction to block header.

Note: this should not require major updates to your codebase.

2. Limit the range of eth_getLogs queries to:

A) Testnet: approximately 2 days (2 * 86400 block) (toBlock — fromBlock)

B) Mainnet: no limit

Note: the change will only affect the Testnet during Phase 1, developers should test the effects of the eth_getLogs change on Testnet during this period so as to prepare for the changes on Mainnet in Phase 2.

3. Security upgrades.

Phase 2: End of the Year

During Phase 2 of the Iris hard fork, major upgrades to the ThunderCore blockchain will take place, including:

1. The ThunderCore go client will be updated to be compatible with geth 1.10.8

2. EVM opcode upgrades:


Note: add the CREATE2 opcode to allow interactions to be made with addresses that do not exist yet on-chain but can be relied on to only possibly eventually contain code that has been created by a particular piece of init code. This is very useful when porting Solidity smart contracts to ThunderCore, for example for state channels that involve counterfactual interactions with contracts.

B) EIP-145: Bitwise shifting instructions in EVM — SHL, SHR and SAR

Note: add bitwise shifting operators in addition to the existing logical and arithmetic operators.

C) EIP-1344ChainID opcode

Note: add the CHAINID opcode to return the current chain’s EIP-155 unique identifier inside the smart contract for better cross-chain compatibility.

3. Limit the range of eth_getLogs queries to:

A) Testnet: approximately 2 days (2 * 86400 block) (toBlock — fromBlock)

B) Mainnet: approximately 2 days (2 * 86400 block) (toBlock — fromBlock)

Note: developers using eth_getLogs should update your Mainnet code accordingly.

The Iris hard fork brings better cross-chain compatibility to the ThunderCore blockchain thanks to the improved EVM compatibility.

Combined with low gas fees, high throughput, and industry-leading security, this makes ThunderCore an ideal Layer-1 chain to migrate your DeFi Dapp to. Get ready for never-before-seen Dapps and services on ThunderCore thanks to the Iris hard fork!

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