Overview

Enclave Cluster is the distributed flavour of Enclave OS (Mini): a set of SGX enclaves that replicate an authenticated ledger through consensus, execute WASM business logic against it, and can prove the cluster's state to third parties. Where a single enclave protects one machine's computation, a cluster keeps serving through machine loss — and keeps its guarantees even when the machines' hosts are the adversary.

The product lives at github.com/Privasys/enclave-cluster (AGPL-3.0): reproducible builds, signed releases with published measurements, and operator documentation.

What you get

• A replicated, authenticated ledger. The state is a versioned sparse Merkle store whose 32-byte root attests everything. The root is encryption independent: every node encrypts its storage with its own key, yet all nodes produce byte-identical roots, so replicas compare entire states as one (version, root) pair.
• Attested consensus. Raft, hardened for the case where every node's host can crash, delay, partition, and roll back disk. Only enclaves whose measurement is in the cluster's admissible set may participate; a rolled-back node cannot double-vote; a node whose state diverges is detected and repaired, not trusted.
• Verified commits. Every node reports the ledger root it computed for each applied entry, and an entry counts as verified only once a quorum agrees on the root. Divergence is attributed — outlier follower, outlier leader, or genuine corruption — and handled automatically where that is safe.
• Commit certificates. Quorum-signed P-256 attestations of (index, root), verifiable offline against keys registered through the replicated log itself. An auditor can prove what the cluster's state was without trusting any single node.
• WASM transactions. Business logic is a Component Model app; a call through the transaction path executes against a fork of the ledger and its write-set commits through consensus. In replay mode, replicas re-execute every transaction deterministically and fail closed unless they reproduce the exact same result.
• A vault-anchored cluster credential. The shared ledger commitment key lives in an Enclave Vaults constellation and is released only to enclaves that pass the credential policy's measurement and TCB checks — on every boot, so revoking a build from the policy takes full effect at the next restart. Obtaining the credential is cluster admission — and cluster upgrades are an owner-approved policy change plus a rolling restart, with no node reconfiguration.
• Bring your own constellation (BYOK). The constellation can be customer-owned: address it directly in configuration, issue key-creation grants from your own identity provider, and run your own attestation verifier. No platform control-plane dependency — every admission and upgrade property carries over unchanged, and policy profiles are TEE-typed (SGX MRENCLAVE or TDX MRTD/RTMRs).

Where it sits

The threat model is deliberately unusual: the nodes are honest (their code is measured), but each node's host is not. That single assumption reshapes the consensus layer — voting rights live in replicated membership rather than local disk, and state continuity is confirmed by the quorum rather than asserted by any node. The Architecture page walks through how.