Sidechain · settles to Ethereum
Immutable zkEVM ticker IMX
Summary
An EVM chain operated by Immutable on its own fork of Geth, using Clique proof of authority: only keys that Immutable authorizes may sign blocks, one every 2 seconds. Immutable's bridge design document calls it a single-sequencer, permissioned chain with a fixed validator set, and the mainnet genesis file authorizes one signer. The chain posts nothing to Ethereum, so Ethereum does not verify its state and holds none of its data. Its link to Ethereum is a token bridge: deposits lock tokens in an Ethereum contract, the Axelar network attests the message, and matching tokens are released on Immutable, with the reverse for withdrawals. IMX, an ERC-20 on Ethereum, is the native gas coin here. Block production uses no open stake or work. 14101314151718
Design
- System
- SidechainImmutable zkEVM (chain ID 13371), called Immutable Chain in Immutable's current docs, is filed as a sidechain, not a layer 2. It runs its own proof-of-authority consensus on a Geth fork with signers authorized by Immutable, and is joined to Ethereum only by a token bridge whose messages the Axelar network relays. No data, state roots or proofs go to Ethereum, so Ethereum cannot check the chain or enforce withdrawals. Immutable markets it as a layer 2; L2BEAT calls it a sidechain that plans to become a ZK rollup. No zero-knowledge proofs are used today. IMX is the gas coin.
- Settles to
- EthereumNot settlement in the rollup sense. Ethereum holds the bridge escrow and the ERC-20 form of IMX. Deposits take about 15 to 30 minutes through Axelar; withdrawals take up to 24 hours, because large ones or those during heavy outflow are queued for a day. No transaction data, state roots or proofs of this chain are posted to or verified on Ethereum.
- Settlement family
- Ethereum / EVM
- Scarce resource
- Reputation
- State model
- Accounts
- Finality
- Other
- Who makes blocks
- Block signers authorized by Immutable under Clique. The mainnet genesis authorizes a single signer, and Immutable's bridge document describes a single sequencer with a fixed validator set. Anyone may run a public follower node, but such nodes forward transactions to Immutable's RPC instead of gossiping them and cannot produce blocks.
- Fork choice
- Clique normally prefers the chain with the most in-turn signed blocks, but with one authorized signer there is no competing producer. Immutable's network configuration makes nodes treat any reorganization as an error, and its node software includes an operator command that rewinds the chain to an earlier block and, on the validator, resumes production from there. Ethereum plays no part in ordering.
Qualifications
- Scarce resource · Partial. Blocks are signed by keys that Immutable authorizes; there is no open stake or work. What is scarce is the operator's identity and accountability, not a measured score. IMX staking offered by the IMX Ecosystem Foundation is not described as block production.
- Finality · Partial. Immutable's docs state finality of about 2 seconds. That rests on operation, not on a finality protocol: Clique has no finality rule, nodes are configured to refuse reorganizations, and the operator's node software can rewind the chain. Ethereum does not finalize these blocks.
- Decentralization · Partial. Anyone may run a follower node and read or transact on the chain, but block production is limited to Immutable-authorized signers and the canonical bridge is operated only by Immutable.
- Proof system · Not applicable. No validity or fraud proofs are produced or checked on Ethereum. The zkEVM name reflects a plan; Immutable's bridging page says the bridge uses Axelar today, with plans to add ZK proofs in the future.
- Layer 2 label · Contested. Immutable's chain page calls it a layer-2 blockchain and its docs describe Ethereum as L1 and Immutable Chain as L2. L2BEAT lists it among Others as a sidechain because it has no working proof system and no data on Ethereum. This profile follows the sidechain reading.
- Upgrade authority · Applies. Per L2BEAT, a 4-of-6 multisig controls the ProxyAdmin that upgrades the Ethereum bridge escrow and its Axelar adaptor, with no delay, so users have no window to exit before an unwanted upgrade. Bridge roles can also pause deposits and withdrawals.
Tradeoffs
- Emphasizes
- Scalability
- Gives up
- Decentralization and independent security. Immutable-authorized keys sign every block, Ethereum does not check the chain's state or hold its data, and the bridge depends on Axelar validators and on contracts that a 4-of-6 multisig can upgrade with no delay.The scalability emphasis refers to 2-second blocks and Immutable's gas sponsorship for players using its Passport wallet, not to any sourced throughput figure. Immutable says it plans to add ZK proofs to the bridge; no timeline was found, so until then safety rests on Immutable's operation and on Axelar.
- Full node at home
- Practical at home 412Immutable's node guide asks for 2 AWS vCPUs, 4 GB RAM and 100 GB of free storage for a permissionless public node, while the immutable-geth README asks for at least 1 TB of storage to sync mainnet (4+ cores, 16 GB RAM and a fast SSD recommended); the storage figures conflict. A public node re-executes blocks but forwards transactions to Immutable's RPC rather than gossiping them, and cannot take part in block production. Private nodes need allowlisting by Immutable.
- Throughput claims
- No classified figure recorded
Scaling layers
No scaling layer recorded in this profile.
Capabilities
| Capability | How it is provided | Notes and sources |
|---|---|---|
| Account abstraction | Structured assessment pending | Not yet assessed for any chain. |
| Atomic swaps | Core-team softwareLimited scope | Immutable's Orderbook: an application contract that Immutable, the chain's steward, runs with its order API settles a signed NFT listing or bid against payment in one on-chain transaction. Scope is limited: it is application software, not a chain primitive; it covers NFT listings and bids against payment on this chain; and orders reach it through Immutable's order API. No protocol-level swap mechanism was reviewed; EVM contracts could implement hash-locked swaps, but none was verified. 8 |
| Authenticated data publication | Unknown | Not yet assessed under this row's current definition. |
| Light clients | Unknown | No light client for this chain was documented. Clique block headers carry signer signatures that could in principle be checked, but no such tool was reviewed, and Ethereum holds no state roots to check against. |
| Native staking or delegation | Structured assessment pending | Not yet assessed for any chain. |
| On-chain governance | Structured assessment pending | Not yet assessed for any chain. |
| Parallel execution | Structured assessment pending | Not yet assessed for any chain. |
| Payment or state channels | Unknown | No payment or state channel layer anchored to this chain was found; absence was not exhaustively verified. |
| Programmable spending | Native (protocol or core-team software) Earlier definition | The chain runs Ethereum smart contracts up to the Cancun fork, with differences such as no blob transactions and a PREVRANDAO value of zero. Passport wallets are themselves smart contracts. 29 |
| Protocol-verified messaging | Structured assessment pending | Not yet assessed for any chain. |
| Reversible transfers or recovery | Core-team softwareLimited scope | Recovery comes from a wallet product run by the chain's steward, Immutable, not from the protocol. Immutable's Passport wallet is a 2-of-2 smart-contract wallet: the user's key, which the Magic service generates and stores, plus an Immutable guardian key that enforces spending limits and fraud checks. Users regain access by logging in again with the same identity provider; the co-signing guardian key is not itself a recovery path. Limited: part (b) only; there is no protocol feature, user-set schedule or time-locked vault for cancelling or delaying a payment. 9 |
| Rollups | Unknown | Rollups anchored to this chain were not reviewed. Immutable X, Immutable's earlier StarkEx-based network, settled on Ethereum, not here, and was shut down in February 2026. 616 |
| Shielded transfers | Structured assessment pending | Not yet assessed for any chain. |
| Signed partial offers | Unknown | Not yet assessed under this row's current definition. |
Reading these values
- How this feature is provided
- Built into the protocol, core-team software or independent software says where a feature lives and who can change it. These are implementation layers, not quality: core-team software is not closer to the protocol than independent software.
- Structured assessment pending
- The shared review has not assessed this feature for any chain yet (Account abstraction, Native staking or delegation, On-chain governance, Parallel execution, Protocol-verified messaging and Shielded transfers). That does not mean it is absent, and a chain’s profile may already describe it.
- Unknown
- The review has not established this for this chain under the current definition; the note beside it says why. Unknown is not absent and not a low score. A feature reads “Not present” only when a source shows it is absent.
- Earlier definition
- Payment or state channels, Programmable spending and Rollups keep the earlier definition until the next fact-check. There, “Native” does not separate the protocol from core-team software, “Ecosystem software” does not say who publishes it, and “Partial” does not say which layer.
- Reading across rows
- The list of capabilities is incomplete. Do not read these rows as a chain leading or lagging overall.
Ecosystem & custody
| Product type | Status | Notes and sources |
|---|---|---|
| Automated market makers | Established in the ecosystemQuickSwap (V3 deployment) | Immutable's swap widget routes token swaps through QuickSwap, and QuickSwap's contract list includes an Immutable zkEVM V3 deployment. Only allowlisted tokens appear in Immutable's widget. Liquidity depth was not measured and other venues were not reviewed. 720 |
| Issuer-native stablecoins | None found | USDC and USDT on this chain are representations minted by Immutable's canonical bridge against tokens locked on Ethereum, not issuer-issued. Circle's native USDC list does not include Immutable, and Tether's list of chains where it issues USDT does not include it either. 32122 |
| Algorithmic stablecoins | Unknown | Algorithmic or hybrid stablecoins on this chain were not reviewed. |
| Bridges | First-partyImmutable canonical bridge (Ethereum, Axelar messaging), LayerSwap, Squid | Immutable's docs list its canonical bridge for ETH, IMX, USDC, USDT, wBTC and other mapped Ethereum ERC-20 tokens, and name LayerSwap and Squid as third-party routes. Immutable alone operates the canonical bridge and Axelar relays its messages. NFTs and tokens created on Immutable cannot use it. Risk: L2BEAT reports no state validation: Axelar validators could mint unbacked tokens or relay a withdrawal that never happened, and a 4-of-6 multisig can upgrade the Ethereum contracts with no delay. Withdrawals above per-token limits, or during heavy outflow, are queued for 24 hours, and Immutable can pause the bridge. Third-party bridges were not assessed. 3101117 |
| Block explorers | First-partyImmutable Explorer (explorer.immutable.com, Blockscout software) | Immutable's network configuration names explorer.immutable.com as the mainnet explorer; the site runs Blockscout. No independent second explorer was verified. Explorer data is indexed by its operator and is not consensus. 119 |
| Hardware wallets | ThinTrezor Safe 3, 5 and 7 (through MetaMask or Rabby) | See custody rows: Trezor's IMX page lists the Immutable zkEVM network, but Trezor Suite's own network configuration does not include it, so Trezor use goes through third-party wallet apps. Ledger's IMX page describes the token on Ethereum and does not mention Immutable zkEVM. Immutable's Passport wallet, which most players use, is not described as supporting hardware signers. 9232425 |
Hardware-wallet custody
| Device maker | Status | What users can and cannot do |
|---|---|---|
| Ledger | UnknownSame as native: Unknown | Ledger's ImmutableX page says IMX can be bought, sent, swapped and staked in Ledger Wallet, but it describes IMX as a token of Immutable X on the Ethereum blockchain and never mentions Immutable zkEVM, so it shows support for the Ethereum token, not for this network. Ledger's support articles for Immutable load by script and could not be read, so network support was not confirmed either way. 25 |
| Trezor | Through an intermediaryMetaMask or Rabby (third-party wallet apps named on Trezor's IMX page)Same as native: Unknown | Can: Use a Trezor Safe 3, Safe 5 or Safe 7 on the Immutable zkEVM network through MetaMask or Rabby, confirming transactions on the device; Trezor's IMX page lists Immutable zkEVM among the networks for these models Cannot: Add an Immutable zkEVM account in Trezor Suite: the EVM network list in Trezor Suite's public source code does not include the chain (ID 13371), although Trezor's IMX page names Trezor Suite as a compatible appTrezor's evidence conflicts: its IMX page lists Ethereum and Immutable zkEVM as networks and names Trezor Suite, but Suite's network configuration has no Immutable chain, so the Suite listing may refer to IMX as a token on Ethereum. The page still calls IMX the token of the Immutable X network. Older Trezor models and Passport wallets were not reviewed. 2324 |
Public data
iKnow Blockchain has no public-data lookups for Immutable zkEVM yet. This is a limit of the service, not a statement about the network.
| Lookup | Status | What it covers and its limits |
|---|---|---|
| Address or account | Not available yet | Public-data lookups for this chain are not built yet. |
| Tokens and assets | Not available yet | Public-data lookups for this chain are not built yet. |
| NFTs | Not available yet | Public-data lookups for this chain are not built yet. |
| Transactions | Not available yet | Public-data lookups for this chain are not built yet. |
Sourced developments
Developments: Review overdue Reviewed Sep 27, 2026; next review was due Oct 7, 2026, 12:00 UTC.
Publication date · newest first
-
Immutable X was shut down and remaining funds moved to Immutable zkEVM
Immutable sunset its older StarkEx-based network, Immutable X, with 11 February 2026 as the last day for manual withdrawals. Between 5 and 9 March 2026 an upgrade of the Immutable X bridge moved remaining user funds to Immutable zkEVM, where a contract pays them out only against proofs of ownership from the final Immutable X state.
- Implementation:migration and disbursement contracts deployed; Nethermind audit published
- Release:Immutable X sequencer no longer accepts transactions; marketplace removed
- Activation:complete: automated migration ran 5 to 9 March 2026
Sources: Immutable (GitHub) — Immutable X Asset Migration Contracts (external site) · Immutable Documentation — Immutable X Deprecation (external site)
-
Node software release v1.0.0-beta.17 patched a Geth denial-of-service flaw
Immutable released immutable-geth v1.0.0-beta.17, which brings in the upstream Geth fix for CVE-2026-22868, a moderate-severity flaw where a crafted peer-to-peer message could cause high CPU use. The release also added build attestations to the published images.
- Implementation:upstream Geth fix brought in (release note item: Address CVE-2026-22868)
- Release:v1.0.0-beta.17 published
- Activation:no network upgrade involved; applies when each operator updates
Sources: Immutable (GitHub) — immutable-geth v1.0.0-beta.17 (external site) · go-ethereum (GitHub security advisory) — DoS via malicious p2p message (CVE-2026-22868) (external site)
Topics your AI can explain
Your AI can explain these topics for Immutable zkEVM through the connection, with sources.
Known gaps
What this profile's review did not establish:
- Immutable's docs do not say how many block signers run today or who holds and secures the signing key. The mainnet genesis authorizes one signer; checkpoint blocks read from the public RPC in this review also listed one.
- No rule was found for when a block becomes irreversible beyond the docs' 2-second claim, and no public record of past operator rewinds was found.
- The node software can filter transactions by sender or recipient address lists; whether Immutable's production nodes use such a list was not documented.
- Node storage requirements conflict: 100 GB in Immutable's node guide versus at least 1 TB in the immutable-geth README.
- No design or timeline was found for the ZK proofs Immutable says it may add to the bridge. L2BEAT describes the chain as powered by the Polygon stack, which does not match Immutable's current docs (a Geth fork using Clique).
- Where transaction fees end up, the IMX supply on this chain and how the IMX Ecosystem Foundation's staking works (its page loads by script) were not reviewed.
- Ledger support for the Immutable zkEVM network was not confirmed: Ledger's coin page covers IMX on Ethereum, its support articles render by script, and its published wallet code could not be read in full.
- Trezor's IMX page names Trezor Suite, but Suite's source lists no Immutable chain; whether Trezor intends Suite support for the network was not confirmed.
- Whether Immutable Passport wallets can use Ledger or Trezor as a signer was not verified.
- Liquidity on QuickSwap, other exchanges and algorithmic stablecoins were not reviewed.
- Axelar validator figures in Immutable's bridge document (75 validators, 60 percent threshold) may be out of date; Axelar's current validator set was not checked.
- Light clients, channels and any chains anchored to Immutable zkEVM were not reviewed, so no scaling layer is listed.
Sources
Oldest dated source check: Source checked Sep 27, 2026 Next check due Oct 27, 2026.
- Immutable Chain (network configuration) (external site)
- Differences from Ethereum (external site)
- Bridging (external site)
- Running Nodes (external site)
- Native Token (external site)
- Immutable X Deprecation (external site)
- Swap (Checkout widget) (external site)
- Orderbook (external site)
- Passport Architecture (external site)
- Immutable zkEVM token bridge: high-level architecture (external site)
- zkevm-bridge-contracts (external site)
- immutable-geth (external site)
- Mainnet genesis settings (mainnet.json) (external site)
- Chain configuration (params/config.go) (external site)
- Rewind chain command (immutable_rewind_command.go) (external site)
- Immutable X Asset Migration Contracts (external site)
- Immutable zkEVM (external site)
- EIP-225: Clique proof-of-authority consensus protocol (external site)
- Immutable Explorer (external site)
- Contracts and Addresses (external site)
- USDC Contract Addresses (external site)
- Supported Protocols (external site)
- Trezor Suite Ethereum network configuration (networkConfig.ts, develop branch) (external site)
- Immutable wallet (IMX) (external site)
- ImmutableX wallet (external site)
Report an error
Found something wrong or out of date? Reporting is free, and every chain goes through the same process. Published corrections appear in the public log.
Funding disclosure
Funding disclosures appear here when an upkeep arrangement exists, in the form “Upkeep funded by [name]; verdicts unaffected.” The funder ledger has not been published yet. Neutrality & funding