Fork troubleshooting

“Old state not supported”

Remote node does not have StateService FullState: true. Use a FullState-enabled RPC endpoint.

Slow first contract call

Remote storage is fetched lazily. Run nanvil fork prefetch for the contract hash first.

Proof verification failed

Branch state root may be stale. Recreate manifest at a recent block height.

Missing contracts

Only contracts deployed at branch height appear in the manifest. Deployed-after-branch contracts exist only on the public chain.

Cache issues

Delete --fork-cache-path directory and restart, or use --no-storage-caching for debugging.