Ethereum developers are testing a Fast Confirmation Rule (FCR) mechanism that will reduce transfer times between the main network and Layer 2 from 13 minutes to just 13 seconds. This was shared by ecosystem researcher Julian Ma.
— Julian (@_julianma) March 17, 2026
Currently, users rely on bridges. Transactions await multiple confirmations or full finality. Many exchanges and Layer 2 solutions do not wait for this and instead use the k-deep rule: an operation is considered final only after a certain number of blocks have passed. However, this approach does not provide formal guarantees.
How FCR Works
Instead of counting blocks, the mechanism analyzes validator attestations to determine whether a record in the chain can be safely considered confirmed, thus speeding up bridge operations. The rule operates under two assumptions:
- The network is fast enough, and validator messages arrive within seconds.
- No participant controls more than 25% of all ETH in staking.
These conditions are less stringent than Ethereum's full finality requirements, but they are sufficient for most practical purposes.
“When a node detects that more security is needed, it waits longer before quickly confirming a block. This is not a flaw but a feature,” explained Ma.
The developer noted that implementing the new rule will not require a hard fork—developers are already integrating it into clients and APIs. Once deployed, nodes will be able to use the mechanism without coordination across the network. Exchanges, Layer 2 solutions, and infrastructure projects are expected to adopt it with minimal adjustments.
Community Reaction
Co-founder Vitalik Buterin endorsed the mechanism, stating that under certain conditions, FCR provides a "hard guarantee" that an operation will not be reverted after just one slot—approximately 12 seconds.
A new fast confirmation rule mechanism lets you get a hard guarantee that Ethereum will not revert after one slot (12 seconds)
— vitalik.eth (@VitalikButerin) March 18, 2026
Security assumptions are (i) supermajority honest, (ii) network latency under ~3s. So one step below economic finality, but very strong for many use…
However, the community's response has been mixed. A user under the pseudonym serx pointed out that the security of the mechanism relies entirely on the honesty of the majority of validators. If this assumption fails, the entire structure could collapse.
Some expressed doubts about whether the foundational assumptions of FCR would hold up under real-world stress and remain functional.
12-second near-finality is huge for UX
— CryptoJoeXX (@IHeddaji) March 18, 2026
But can those assumptions hold under stress?
It is worth noting that in February, an Ethereum Foundation member under the pseudonym ladislaus stated that the network is transitioning from re-executing all transactions on nodes to confirming the correctness of operations using zkEVM.
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