What the sequencer is, and what it isn't
The sequencer is the L2's traffic officer. It collects transactions, orders them, builds blocks, and posts batches to Ethereum. On most rollups, the sequencer is the most powerful piece of the architecture: it controls ordering, can extract MEV, and can in principle censor users.
On EDMA, the sequencer is intentionally narrower. It controls ordering. That's it. It does not decide who gets paid, whether a token is valid, or whether evidence is real. Those decisions are enforced at the contract level by the PoV gate, the One-Claim ledger, and the EMT mint logic. The simplest way to describe the split: the sequencer controls ordering. PoV controls admissibility.
That separation matters because it puts a hard limit on what the sequencer can do, even if it's malicious. A bad-actor sequencer can reorder, delay, or front-run transactions. It cannot bypass PoV, mint EMTs out of thin air, move Locked EDSD without a verified pass, skip burns, or accept duplicate evidence. Those are blocked in contracts, not in sequencer code.
What the sequencer does, day to day
Ordering & block production
Collects RFQs, awards, funding, proof submissions, EMT mints, and release calls. Orders them, executes them, produces L2 blocks at a ~2s target. Application receipts emit immediately.
Batching to Ethereum
Bundles L2 blocks into EIP-4844 blobs and posts to Ethereum every 2-10 minutes (or sooner under load). State roots and commitments go on-chain so anyone can reconstruct the state.
Priority paths
Proof-aware boost. Transactions that finalize an already-verified gate-pass (mint EMT, release EDSD) get a small, published priority over non-critical calls so cash isn't held back by noise.
Gas via Paymaster
Coordinates with the Paymaster so users pay gas in $EDM or EDSD instead of ETH. The Paymaster settles the tiny ETH to the sequencer behind the scenes.
Protections against bad sequencer behaviour
- 01
Forced inclusion via Ethereum L1 inbox
If the sequencer censors a transaction (won't include it in a block), anyone can post the transaction directly to an Ethereum L1 inbox contract. The next batch posted to Ethereum is required to include it. Censorship is not just penalised; it is bypassable.
- 02
Permissionless exits
Even if the sequencer goes fully offline, users can force-withdraw $EDM and EDSD back to Ethereum mainnet after the challenge window. Funds are never trapped on EDMA. The exit mechanism doesn't depend on EDMA's cooperation.
- 03
FIFO ordering, no private lanes
Within a transaction class, the queue is first-come, first-served. EDMA does not sell priority inclusion for EMT-to-release flows. Operators cannot front-run, insert, or reorder transactions for economic gain. Violations are grounds for rotation and slashing once multi-operator is live.
- 04
Inclusion lists
Governance can publish bounded inclusion lists for critical flows (EMT mint, release, forced withdrawal) so these calls cannot be starved. Settlement-critical operations always get through.
- 05
72-hour timelock on sequencer upgrades
Any change to sequencer software that affects ordering or inclusion has a 72-hour timelock with a public diff. Sudden behavioural changes are not possible. Users and integrators have time to audit and respond.
