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+# Coordinator-Driven Historical Execution Replay Milestone
+
+## Goal
+
+Replay every root-confirmed QuarkChain mainnet minor block from genesis through four `goshard` slaves, driven by a dedicated coordinator, with results identical to `pyquarkchain`.
+
+## Scope
+
+The milestone includes:
+
+- QKC data types, including blocks, transactions, receipts, logs, and state encoding.
+- QuarkChain EVM compatibility.
+- Multi-native-token state and execution.
+- Minor-block execution, finalization, result validation, and state persistence.
+- Cross-shard transaction generation, delivery, ordering, and execution.
+- A replay coordinator for canonical input, branch routing, root advancement, barriers, and mismatch reporting.
+
+The milestone excludes:
+
+- Minor-block PoW/PoSW seal and difficulty validation.
+- Root-chain fork choice and root-driven shard reorgs.
+- Mining, txpool, live P2P sync, public RPC, and master compatibility.
+
+## Final Test
+
+1. Start four Go slaves with fresh databases, covering every historical mainnet branch, and establish their xshard connections.
+2. Initialize the exact root and minor genesis state for every shard.
+3. Read canonical root blocks in ascending order. For each committed minor header, load the full minor block and send it to the slave responsible for its branch.
+4. Execute minor blocks serially within each branch. Different branches may run in parallel.
+5. For each source minor block, the source slave must route a list, including an empty list, to every eligible destination shard. Each destination shard must persist the list before replay advances.
+6. After all minor blocks and xshard lists for a root block are complete, broadcast that root block as the next trusted canonical root. Only then may later minor blocks consume its deposits.
+7. For every minor block, compare the computed execution outputs with the values committed in the canonical block:
+   - state root;
+   - receipt root;
+   - bloom;
+   - total gas used;
+   - xshard receive gas used;
+   - xshard cursor;
+   - coinbase amount map.
+8. Repeat selected ranges after restarts to verify persistence, idempotent xshard staging, and resumable replay.
+
+## Acceptance Criteria
+
+- Every root-confirmed canonical mainnet minor block is replayed from genesis, with all computed execution outputs matching the values committed in the canonical block.
+- A mismatch stops replay and reports the root block, minor block, branch, height, and mismatched fields.