Fireblocks is the Vault. Sentinel is the Gun.

The Confusion in the Market

When people hear "ZeroCopy signs transactions inside a Nitro Enclave," the first question is often: "Isn't that what Fireblocks does?"

It is a fair question. Both involve hardware, both involve signing keys, both target institutional crypto. But the use cases are fundamentally different — and understanding why matters for how you architect a serious trading operation.

Fireblocks is Custody Infrastructure

Fireblocks is built to solve the custody problem: how do you hold large amounts of digital assets securely, with multi-party approval workflows, audit trails, and institutional-grade access controls?

Their MPC-based architecture is optimized for:

• Cold and warm storage of assets at scale
• Multi-person approval workflows for large transfers
• Role-based access control across teams
• Regulatory reporting and compliance auditing
• Integration with exchanges and OTC desks

Fireblocks is excellent at what it does. The latency is measured in seconds to minutes. For custody workflows — where a $50M transfer requires three approvals and a compliance review — that is exactly right. You do not want that to happen in 42 microseconds.

Sentinel is Execution Infrastructure

Sentinel is built to solve the execution problem: how do you give an autonomous agent signing capability without giving it unlimited power?

The threat model is entirely different. You are not protecting against an external attacker stealing funds from cold storage. You are protecting against your own system exceeding its authorized operating boundaries — whether due to a bug, an adversarial input, or a market condition that triggers edge-case behavior.

Sentinel is optimized for:

• Deterministic 42µs signing latency — fast enough for live market participation
• Policy enforcement at the signing layer — rate limits, value caps, sanctions
• Hardware kill switch — blocks all signing without agent override
• Verifiable Policy Proofs — cryptographic evidence for every action
• Autonomous agent support — no human approval per transaction

The 95/5 Architecture

The firms building serious agentic trading infrastructure use both:

95% of your assets stay in Fireblocks — cold, multi-sig, fully auditable. The 5% that your agent actively trades with lives in Sentinel-managed wallets, where signing is fast enough for live markets and policy enforcement is hardware-enforced.

This is not a compromise. It is the right architecture for each use case. Fireblocks was not designed for 42µs latency — it does not need to be. Sentinel was not designed for multi-sig treasury management — it does not need to be.

Why Firms Try to Use the Vault as a Gun

The consolidation instinct is understandable. Fewer vendors, fewer integrations, fewer security surfaces. The reasoning goes: "We already have Fireblocks for custody. Can we just use their API for trading too?"

The answer is technically yes and operationally no. Fireblocks transaction authorization is not designed for sub-millisecond turnaround. Routing every agent decision through an MPC approval workflow introduces latency that eliminates most alpha in high-frequency strategies. More importantly, Fireblocks' policy engine is not designed for the per-request, hardware-attested enforcement that EU AI Act Article 14 requires.

The vault is excellent for what it does. So is the gun. You need both.

Integration Pattern

# Treasury flow (Fireblocks)
treasury.transfer(
    amount=50_000_000,    # $50M
    to="hot_wallet",
    approvals=["CFO", "Risk", "Compliance"],
    reason="Weekly trading capital reload"
)

# Trading flow (Sentinel)
sentinel.sign(
    transaction=trade_order,
    policy="high_frequency_policy_v3"
    # 42µs — no human approval required
    # Policy enforced in hardware
    # VPP generated automatically
)

Fireblocks handles the capital transfer to the hot wallet — with full multi-approval governance. Sentinel handles the active trading decisions — with hardware-enforced policy and zero latency overhead.

The Competitive Reality

We are not competing with Fireblocks. We talk to the same firms they do, and in the conversations where Fireblocks comes up, our answer is always: "Keep using them. Use us for the part they were not built for."

The firms building the most sophisticated agentic trading operations are not choosing between custody infrastructure and execution infrastructure. They are building both, because they understand that a vault and a gun are different tools for different problems.

The firms that try to use one for both end up with trading operations that are either too slow or too dangerous.