Cobalt

Cobalt is TEE-as-a-service: a hosted way to run app backends inside a Trusted Execution Environment instead of a black box you just have to trust. App logic runs inside an AWS Nitro Enclave, a hardware-sealed environment, and Monad only accepts a result after AWS's own hardware has proven, via a signed attestation, exactly which code produced it. Not even root access to the host machine can see inside the enclave or forge its output.

Built as a platform first, not a single app: the on-chain registry and the enclave server template don't know anything about the specific app running inside them, so cobalt deploy <app-dir> is a single command for the rest of the project's life, whatever you point it at.

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The chain: attest → register → verify

P384Verifier → CertManager → NitroValidator → EnclaveRegistry vendors a "hinted" on-chain Nitro attestation verifier: the expensive modular-inversion math is computed off-chain and submitted as a hint the contract only checks, not computes, bringing full attestation verification down from infeasible gas to a handful of transactions. EnclaveRegistry is multi-tenant from the start: any number of apps register against the same deployed registry, keyed by appId, with a full PCR set binding, signer TTLs, explicit rejection of all-zero (debug-mode) measurements, and config-version invalidation that can atomically cut off every existing signer and allowed image at once.

Every enclave-signed message goes through EIP-712, not a hand-rolled intent scheme: mandatory deadline and nonce on every message type, chainId/verifyingContract binding for replay protection, and wallet-displayable typed data for free.

The enclave: secp256k1, attestation-gated secrets, no network by default

enclave-server/ is a reusable Rust template: a fresh secp256k1 keypair every boot (so on-chain verification is a plain ecrecover, not hand-rolled Ed25519), an outbound-network allowlist, a health-check endpoint, and attestation-gated KMS secrets, where a secret is only ever decrypted from inside an enclave presenting a matching attestation, never visible in transit or to whoever holds the cloud credentials. Apps are drop-in modules under examples/<name>/, wired in by a one-line include; app code never lives inside the server template itself.

The CLI: cobalt deploy

tools/cobalt.js runs the full sequence against the live registry, end to end: attest (build or reuse a cached enclave image, boot it, pull a real hardware attestation) → createApp → setAllowedImage → registerEnclave → verify (isValidSigner read-back). The first deploy of a given app is a genuine uncached build; every deploy after that hits an S3 artifact cache and just downloads and boots. Image building is decoupled from image launching, which turned the single biggest time cost (a cold hermetic cross-compile, 20–70+ minutes) into a seconds-to-low-minutes operation.

examples/ping proves the pipeline (send a message, get an EIP-712-signed reply back, verified by PingConsumer.sol); examples/dice is a hardware-attested random number an operator can't rig.

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Live on Monad testnet

All five contracts (P384Verifier, CertManager, NitroValidator, EnclaveRegistry, and the PingConsumer example) are deployed and source-verified on MonadVision (Sourcify-backed). A read-only dashboard shows registered apps, allowed images, and signer state straight from that live registry; it doesn't deploy anything itself, cobalt deploy does.

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Stack

• Solidity (Foundry): the on-chain attestation registry, EIP-712 consumer SDK, vendored Nitro validator
• Rust: the enclave server template, secp256k1/EIP-712 signing, NSM attestation
• Node.js: the cobalt deploy/status CLI
• AWS Nitro Enclaves, KMS attestation-gated decrypt
• Monad testnet (EVM)