London Fork Enhancements
Hello Fuse community,
I’m thrilled to share some key updates from the London Fork to enhance the developer experience and smart contract capabilities on the Fuse Blockchain. These changes are primarily drawn from improvements initially proposed for Ethereum and have been adapted to benefit our network. The changes are currently live on the Fuse Sparknet (Testnet), and they will be coming to the Mainnet when the Open Ethereum client is completely replaced with the Nethermind Client. Let’s dive into the details:
1. Implementation of EIP-1559 on the Fuse Network Testnet! 
Improved Fee Market: EIP-1559 introduces a dual-component fee structure:
- Base Fee: This fee automatically adjusts based on network demand and is burned, enhancing predictability and reducing fee volatility.
- Priority Fee (Tip): Directly rewards validators for quicker transaction processing.
Benefits of EIP-1559 for Developers on the Fuse Network:
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Simplified and Predictable Fees: EIP-1559 makes gas fees more stable and easier to estimate. Developers can confidently predict transaction costs, leading to more accurate budgeting and smoother deployment of smart contracts.
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Enhanced Transaction Efficiency: The new fee structure incentivizes faster transaction processing and helps control fee volatility, improving overall network efficiency and user experience. This makes developing and interacting with blockchain applications more straightforward and reliable.
This enhancement marks a significant step towards a more efficient and user-friendly Fuse Network! 
2. Introduction of the BASEFEE Opcode (EIP-3198)
A significant upgrade is the introduction of a new opcode, BASEFEE, within the Ethereum Virtual Machine (EVM). This opcode allows smart contracts to access the base fee per gas of the block in which they’re executed. The base fee reflects the minimum per-gas price needed for a transaction to be included in the block and was a key component introduced in EIP-1559 to help stabilize transaction fees.
Implications for Developers:
This enhancement is particularly beneficial for developers creating smart contracts that involve gas fee calculations or those needing on-chain gas price oracles. By accessing the base fee directly in your contracts, you can design more efficient and economically stable applications.
3. Reduction in Refunds for Certain Opcodes (EIP-3529)
We are adopting changes proposed in EIP-3529, which involve reducing the gas refunds for SSTORE and SELFDESTRUCT operations. This update aims to prevent patterns that could potentially abuse gas token creation and destruction, which could exploit block gas limits.
Implications for Developers:
The reduction in refunds will necessitate a shift in how some contracts are designed, particularly those relying on these operations for gas efficiency strategies. The update is intended to simplify the gas cost analysis per block and ensure a healthier network by discouraging practices that manipulate gas usage.
4. Rejection of New Contracts Starting with the 0xEF Byte (EIP-3541)
Another change we’re implementing is inspired by EIP-3541, where new contracts starting with the 0xEF byte will be rejected by the network. This measure is proactive, setting the stage for future innovations in contract types.
Implications for Developers:
For developers, this means that when deploying new contracts, ensuring that the bytecode does not start with 0xEF is crucial. This change is designed to eliminate ambiguity in contract formats, paving the way for introducing new and enhanced types of contracts without compatibility issues.
Moving Forward
These updates are part of our ongoing commitment to ensure Fuse Blockchain remains a cutting-edge platform that not only meets current developer needs but also anticipates future trends and requirements. As we integrate these enhancements, we welcome your feedback and are here to assist with any questions or transition support needed.
Thank you for your continued support and engagement in making Fuse Blockchain a robust and innovative platform. Let’s keep pushing the boundaries of what’s possible together!
Warm regards,
Fuse Network Team.