Sources and limits
ECHO replays a recorded first hour of a real Arc launch against a proposed config, on Circle’s arc-anvil fork, and compares the outcome to what actually shipped. This page states exactly what is real, what is measured, and where the method stops.
Method
All price paths are produced by executing the real launch contracts inside Arc-Anvil against the exact sequence of trades recorded from mainnet. No synthetic volume or assumed slippage is added. The buyer tape is rebuilt from Uniswap v4 Swap events and Arc’s own Transfer logs, then re-issued as equivalent intents from impersonated senders, with the fork’s clock advanced explicitly to match the original block cadence — because the original signed transactions target a pool that no longer exists under a changed config.
This build is a prototype: nothing has run on arc-anvil yet
Circle’s arc-foundry toolchain (v0.8.0-1) ships darwin-arm64 and Linux binaries only — no Windows build — so arc-anvil has to run under WSL or a Linux runner, and it has never been run against a real Arc launch from this environment yet. Every number this site shows you (price trace, sniper share, LP drain block, close-vs-shipped) is a deterministic, clearly-labelled simulation of what that flow will look like, not a measurement from a real fork. The first step to a real build: run arc-anvil under WSL, fork Arc at the block of a launch that already happened, replay that launch’s own original config, and show that the replayed first hour matches what actually occurred on chain.
Sniper share is measured, never predicted
Once real, sniper concentration on a run will be computed directly from the real, already-recorded buyers of that historical hour — a measurement, not a forecast. New o1 Launchpad launches on Arc currently carry no anti-snipe surcharge, so for any hypothetical future launch that number would be a guess; ECHO will never present a modelled sniper as an observation.
The tape is young
Arc is a new chain. “Ten past launches” today means ten small, young first hours, and a config tuned against a near-empty tape teaches less than one tuned against a mature one. Reference hours are added weekly as more launches complete their first hour.
Decimals
USDC on Arc carries 18 decimals as the gas asset and 6 decimals through its ERC-20 interface on the same balance. A real replay must read every fill through the correct interface for its role; assuming 6 decimals throughout would overstate balances by roughly a trillion times.
Coverage and what’s proposed, not yet live
Session history, run storage and comparison are session-scoped in this build (kept in your browser’s session storage, not a server) — a run link opened in a different tab or after the session ends will read “Run not found.” Persistence, auth and any account-level history are proposed only and will be verified before being claimed as available. No wallet connection is required to read public rehearsal data; ECHO never holds user funds.
Contact & sources
ECHO is built to run on public archive nodes: Arc’s public RPC (archive-capable at depth), Uniswap v4 pool events and Arc’s Transfer logs via eth_getLogs. No token information is shown before launch. Full claim list and evidence →