Shared Sequencers: The Heart of the New Web3

In 2025, modular blockchains, AppChains, and rollup networks are showing record activity. But one element is increasingly coming to the forefront — the sequencer. Or more precisely, the shared sequencer.

It is not just a “node for packing transactions.” It is the central point of power, UX, and MEV. Whoever controls the sequencer controls the market.

What is a sequencer?

A sequencer is a mechanism that determines the order of transactions in a blockchain. In rollup networks, it is the one that collects, organizes, and sends data to the Data Availability layer (for example, Celestia or Ethereum).

In traditional L1, the order is formed by validators. In L2, it is most often formed by a centralized sequencer node managed by the project team.

Problem: Centralized Sequencer

Most rollups today use a single sequencer, and this creates risks:

•         Centralization: the project can stop the network or extract the maximum MEV.

•         Outage: if the sequencer crashes, the rollup stops.

•         Censorship: the sequencer can reject unwanted transactions.

•         UX problems: no consistency between rollups = cross-chain chaos.

What is a Shared Sequencer?

A Shared Sequencer is a decentralized network of nodes that can sequence transactions for multiple rollup networks at once.

They act as a common “heart” for different AppChains, providing:

1.      Fast finality

2.      Deterministic ordering

3.      Consistent cross-chain UX

4.      Fault tolerance

Why is this important?

🧠 1. Unified UX

One order — one reality. Less “double spend”, more predictability. Especially important for DeFi and trading.

🚀 2. More reliability

If the sequencer breaks in one network — the shared layer still functions. Uptime tends to 100%.

🧩 3. Eliminating MEV chaos

Shared order = less cross-chain arbitrage and frontrun. New fairness-based MEV distribution models.

🌐 4. Scalability

You can connect new rollup networks as clients. Shared sequencer becomes like middleware between the DA layer and AppChains.

Top Shared Sequencer Projects (2025 Overview)

Example scenario in 2025

You are a Web3 game developer. You deploy AppChain using Fluent. Instead of writing your own sequencer, you just connect to Espresso. Your players get:

•         instant-finality;

•         the same order of actions, even if there are cross-chain tokens;

•         minimal fees and fault tolerance.

And all this - without setting up your own infrastructure.

What's the catch?

1.      Shared sequencer is still a young model.

2.      Revenue distribution mechanisms (MEV, fees) are in development.

3.      Coordination between dozens of rollups requires a new standard.

But the bet has been made. And large L2s are already integrating Shared Sequencers as part of their strategy.

Shared Sequencers vs Centralized Sequencers

Conclusion

If AppChain is your home, then Shared Sequencer is the road through which guests, tokens, data and liquidity come to it.

There will be many chains in the Web3 of the future.

But only a few will provide order in this chaos.

Those who build the right shared sequencer networks will become the central layers of the new crypto economy.