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Now (up to 23.1)

"Shanghai" Upgrade

First fork after Mainnet, whatever it is called. Bullets are notional until committed to on All-Core-Devs calls.

• Withdrawals from the beacon chain 
• New Push0 op-code and gas costing changes 

Client enhancements

• Shanghai devnets & Zhejiang testnet
• Staking withdrawals in Besu
• EOF (delayed, feature complete)testnets
• Execution performance improvements
• Bonsai Stability Refactor (new format, bug fixes, & auto-heal)
• RPC enhancements and improvements (streaming, accuracy/bug fixes, memory usage)

Later (up to 23.4 and beyond)

Cancun Upgrade

• EIP-4488 - Sharding 4844 - Sharding and data availability sampling first steps 
• Ethereum Object Format support
  • Code Segments
  • Jump Tables
  • New Opcodes
• New op-codes and gas optimizations 

Modularization of Besu

The goal is to shorten release cycle of Besu, increased adoption of Besu leveraged by composability 

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