I’ve noticed an event that many people may not have fully understood yet—the Ethereum Shanghai upgrade. This upgrade was completed in April 2023, and although it may look like a purely technical update, in reality it is the final missing piece in Ethereum’s transition from PoW to PoS, with far greater significance than meets the eye.

Let’s review the background. Since Ethereum launched in 2015, it has gone through multiple upgrades such as Byzantium and London, but the true turning point was the Merge in September 2022, when Ethereum officially shifted from proof of work to proof of stake. The problem was that after the transition, all staked ETH and rewards were locked on the Beacon Chain, and users couldn’t get them out at all. So this Shanghai upgrade is actually here to solve that issue—by opening up staking withdrawal functionality.

Interestingly, the upgrade was originally planned to be implemented in March 2023, but due to technical reasons it was postponed to April 13. Before that, Ethereum developers also specifically launched a testnet codenamed "Shandong" to troubleshoot the problems. These details really reflect Ethereum’s cautious approach to this upgrade.

When it comes to market impact, this is the part traders care about most. After the upgrade is completed, the earliest users who staked at low prices in 2020 (when ETH was only $500–$600) can start withdrawing their assets and rewards. In theory, this would release a large amount of liquidity, but in practice most people won’t fully exit—mainly, there will be partial withdrawals. Users who started staking from 2021 onward may now be at a loss, so the real sell pressure would mainly come from early participants, which is not expected to be too intense.

On the other hand, the improvement in staking liquidity brought by the Ethereum Shanghai upgrade may attract more new users to participate in staking. Those who previously didn’t want their funds locked may now consider staking 32 ETH directly to become validators. This is positive for ETH’s long-term demand. However, tokens of liquid staking platforms may face pressure, because their unique features are being weakened.

From a technical perspective, this upgrade also brings other important improvements. First, gas fee optimization—especially helpful for Layer-2 solutions like Polygon and Optimism—makes the Ethereum ecosystem faster and cheaper. Second, smart contract upgrades: by introducing EIP-3540 (EVM object format), which separates code and data, the change greatly improves network efficiency. It also adds anti-attack technologies and supports multiple programming languages such as Solidity and Vyper, giving developers more room to choose.

Overall, the Ethereum Shanghai upgrade is essentially laying the groundwork for the ecosystem’s scalability and decentralization. Unlocking staked ETH is only the surface—the deeper goal is to refine Ethereum’s technical infrastructure. That’s also why this upgrade generated more buzz than previous ones: it’s not just a technical update, but a key milestone for Ethereum as the world’s most important smart contract platform.