From 16 Minutes to Seconds A Roadmap to Fast Finality on Ethereum Yann Vonlanthen · Research Scientist, Ethereum Foundation
16 minutesuntil an Ethereum transaction is final The north star: seconds.strawmap.org
Rebuilding proof of stake, in stages. 1RF8453 16 min today 1Decoupled consensus~4 min 2One-round finality< 1 min 3Shorter roundsseconds Finality inseconds
STAGE 1 · DECOUPLED CONSENSUS Today: GasperLMD-GHOST and Casper FFG share one vote. Stage 1: decouple themGoldfish runs the chain. Finality gets its own rounds. Transactionsfinal GasperLMD-GHOST + Casper FFG1M validatorsone vote, for both jobs checkpointGoldfishavailable chainFinality gadgetown roundsconfirmed512every slot1Min their own rounds
STAGE 1 · DECOUPLED CONSENSUS Today’s chain Decoupled: four times faster How safe, how soon finaljustifiedfast confirmednewcheckpoint Todaytwo rounds Decoupled consensustwo rounds 1 min2 min3 min4 min100%50%0Safe againstTime since you sent itFast confirmationTwo rounds33%Today: 33%only at 16 min
EIP-8453 EIPS/eip-8453.md
A full overhaul of consensus. And we can be more ambitious. PQ readyaccountable safetydynamic availability50% fault toleranceinactivity leakenables quick slots fast pathcommittee self-selectionvalidator anonymityminority vetosecret leader electionlean stateperfect reward fairness one-round finality
STAGE 2 · ONE-ROUND FINALITY One round instead of two Faster, but weaker finaljustifiedfast confirmednewcheckpoint Decoupled consensustwo rounds One-round finalityone round 1 min2 min3 min4 min100%50%0Safe againstTime since you sent itFast confirmationTwo rounds33%One round20%
New Result TransactionscheckpointGoldfishavailable chainFinality gadgetone roundconfirmedfinal one waySafety gadgetfinalsafe
NEW PAPERSafetygadget
Blocks get safer, one round later Optimal safety safefinaljustifiedfast confirmednewcheckpoint One round+ safety gadget 1 min2 min3 min4 min100%50%0Safe againstTime since you sent itFast confirmationTwo rounds33%One round20% Safety gadget100%
STAGE 3 · SHORTER ROUNDS finality.watch It all multiplies finality.watchA new tool to trackfinality upgrades TodayDecoupled consensusOne-round finalityBetter networking4-slot roundsConsolidation128k validatorsShorter slots6 seconds finaljustifiedfast confirmednewcheckpoint finality.watchTurn the knobs yourself
Consolidate. Fewer validators, shorter rounds. 2,048ETH
consensus.ethereum.foundation/cambridge
This week at Devcon Francesco D’AmatoWed 10:30 · Lotus Stage 2Fast Finality updateBarnabé MonnotWed 11:30 · Lotus Stage 3Fast EthereumJulian MaWed 17:10 · Lotus Stage 1Fast Confirmation RuleRoberto SaltiniThu 15:00 · Workshop 1Formal Verification of Consensus Protocols in Lean Scan to add all four to your Devcon schedule
The future is bright. 1RF8453 16 minutes seconds Rebuilding proof of stake, in stages. Yann Vonlanthen@yannvonyann.vonlanthen@ethereum.org finality.watchCambridge talksDevcon talks
AppendixNot part of the five minutes. For Q&A.

What this unlocks

Post-quantum readiness

Small committee, PQ signatures as they are

Fixing Gasper

Reorg-resilient chain, separate from finality

Fast finality, quick slots

At least 4× faster, off the critical path

How we got hereSteps ahead2022 – 25ResearchOct 2025CambridgeNot BFT-onlyNov 2025Devconnect ARGFirst designsJan 2026BerlinStrawmapMar 2026ethresear.chDC publicOct 2026CambridgeWorkshop21 Oct 2026EIP-84533 Nov 2026MumbaiDevcon 8We are here I* headlinerdecision Multi-clientdevnets Forkcandidate MainnetYears of researchGoldfish · RLMD-GHOST · TOB-SVD · 3SF · Majorum Not BFT-onlyPlus a stabilization gadget First designs validated DC goes publicUnblocking faster finality with decoupled consensus Cambridge is online Every talk: slides and recordings consensus.ethereum.foundation/cambridge EIP-8453Draft We are hereDevcon 8, Mumbai

Decoupled consensus, as it stands

One transaction, inclusion to finality

~3m 48sexpected · today ~16 min

included
Inclusion6 sec
Confirmation12 sec
Wait for its round54 sec
Justification1m 12s
Finalization1m 24s
NETWORKING From 32 slots to 8 2× and 2× make the 4× faster finality we’re after. One box is one slot. Today32 slots6.4 minPipelining, 2×16 slots3.2 min+ bundling, 2×8 slots96 s Pipelining: more committees per slot. Bundled attestations (EIP-8334): one copy of the data, many signatures.
One round: safety vs. liveness 10%20%30%20%40%60%80%100% 90%80%70%100%90%80% Two rounds One round + safety gadget Safety: attackers tolerated Liveness: offline tolerated Everyone Finalize at 80% of votes safe 20% · live 20% Observers: you choose Wait for 80%safe 60% · live 20% Wait for 90%safe 80% · live 10% Wait for 100%safe 100% · live 0% 2t + 3p < n: Lamport ’02, Dutta et al. ’05 · gadget frontier: OFlex ’24 · labels are the share of votes needed