The Single-Chain Problem
When we started designing Landblock, the easy path was to pick one blockchain and build everything on it. Pick Ethereum. Pick Polygon. Pick Solana. Make a decision, ship fast, and let governments adapt to whatever you chose.
We rejected that path early, and here is why.
Land administration is a sovereign function. Governments do not casually hand their infrastructure choices to a startup. When a ministry of lands evaluates a digital system, they ask hard questions: Who controls this network? What happens if the company behind it fails? What are the geopolitical implications of anchoring our national records on infrastructure governed by another country's legal system?
These are not paranoid questions. They are responsible ones. And if the answer is "you have to use this one specific blockchain because that is what we built on," the conversation ends there.
Beyond the political dimension, there is a practical one. Different blockchains have different tradeoffs — in transaction cost, finality time, validator decentralization, smart contract capabilities, and energy profile. What is optimal for a high-volume urban registry in one country may be entirely wrong for a lower-volume rural registry in another. A single-chain protocol forces every registry to accept those tradeoffs whether or not they fit.
We wanted to build something that governments could actually adopt. That meant building something that did not force them to adopt our infrastructure preferences alongside our protocol.
The Core Idea: Chain-Agnostic Federation
The key insight is this: what matters is not which chain a registry uses. What matters is that the proof it publishes is verifiable by any other participant in the network, regardless of which chain they are on.
In Landblock, every member registry chooses an "anchoring chain" — the blockchain where it publishes its land record proofs. That chain is recorded in the RegistryDirectory, the on-chain index of all accredited member registries. When another registry, court, or institution wants to verify a proof, the federation protocol looks up where that registry is anchored and routes the verification request accordingly.
The registry choosing Polygon gets Polygon. The registry that prefers a different network gets that. The protocol connects them. Neither has to care about the other's internal choice.
This is what "chain-agnostic" means in practice. The Landblock protocol does not care which chain you are on. It cares that you are publishing valid proofs, that you are an accredited member, and that your claims can be verified. The chain is infrastructure. The protocol is the contract.
How the Chains Stay Connected: LayerZero
Making this work requires something that can carry messages and verify state across chains that do not natively communicate with each other. That is what LayerZero does.
LayerZero is a cross-chain messaging protocol. It lets a smart contract on one blockchain send a message to a smart contract on another, with cryptographic guarantees that the message was not tampered with and that it was sent by the correct contract.
In Landblock's case, this means: when a registry anchored on a secondary chain publishes a land record proof, that proof can be relayed to Polygon — our primary chain — where it is stored, indexed, and made available for cross-registry verification. The Federation contract on Polygon receives the message, verifies it came from a trusted peer, and records the proof exactly as it would for a locally submitted proof. From the perspective of anyone querying the network, the proof looks the same whether it was submitted from Polygon or from another chain entirely.
The security of this relay is not dependent on trusting Landblock. LayerZero uses a network of independent verifiers — called Decentralized Verifier Networks (DVNs) — that must each confirm a message before it is delivered. For Landblock's production deployment, we are targeting institutional-grade DVNs, including Google Cloud and Nethermind, to provide the level of verification appropriate for government infrastructure. On testnet, we use LayerZero's default DVNs while we validate the full architecture.
Polygon as Primary, SUI as First Secondary
We made a deliberate decision to designate one chain as primary. Polygon is that chain. All of Landblock's core infrastructure — the governance contracts, the DAO, the token, the main Federation contract, the RegistryDirectory — lives on Polygon. It is where governance votes happen. It is where the authoritative record of accredited registries is maintained.
Having a primary chain is not a contradiction of the multi-chain principle. Every federation needs a canonical reference point. What the multi-chain architecture means is that registries are not forced onto the primary chain. They anchor their proofs wherever fits them, and the protocol handles the rest.
Our first secondary chain is SUI. The choice was deliberate: SUI uses a fundamentally different architecture than EVM-compatible chains like Polygon. It uses the Move programming language rather than Solidity. Its execution model and object-based storage model are entirely different. Successfully connecting Polygon and SUI — EVM to non-EVM — is the strongest possible proof that the protocol is genuinely chain-agnostic, not just compatible with chains that happen to look like Ethereum.
If we can verify a land record proof anchored on SUI from a Federation contract on Polygon, we can verify a proof from any sufficiently capable blockchain. That is the test we are running in Phase 7.
How New Chains Get Added: The DAO Governs the List
One of the most important design decisions in the multi-chain architecture is who decides which chains are supported.
The answer is the DAO — the decentralized governing body of the Landblock protocol, whose voting power is held by accredited registries and founding stewards. Adding a new chain requires a formal proposal, a deliberation period, and a vote. Removing a chain requires a 180-day notice period so registries anchored on that chain have time to migrate.
This matters because it prevents the protocol from becoming a political instrument. If any single company — including us — could unilaterally add or remove supported chains, registries would have no guarantee that their chosen infrastructure would remain supported. The DAO structure means the decision is made by the registries themselves, on a transparent timeline, with defined criteria.
The criteria for chain addition are evaluated across five dimensions: technical maturity, decentralization, security track record, LayerZero support, and geopolitical considerations relevant to the registries considering it. A chain that scores well on all five gets added. A chain that has a poor security record or is insufficiently decentralized does not, regardless of how popular it is.
What This Means for Resilience
A single-chain protocol has a single point of failure. If that chain has a major outage, exploits a vulnerability, or faces regulatory pressure in a key jurisdiction, the entire protocol is affected.
A multi-chain protocol distributes that risk. A problem on one supported chain affects only the registries anchored there. Other registries continue operating normally. Affected registries can migrate to a different anchoring chain — with DAO approval — without losing their proof history or their standing in the network.
This is not a hypothetical resilience argument. Governments evaluating critical infrastructure explicitly ask about it. They want to know what happens when things go wrong. A multi-chain architecture gives a concrete answer: the network continues, migration paths exist, and no single chain failure can take down the federation.
Where We Are Now
The multi-chain infrastructure is actively being built. As of this week, the LayerZero OFT adapters for both the LDBK and LGT tokens are deployed on Polygon Amoy testnet. The Federation contract now inherits the LayerZero OApp base, meaning it can receive cross-chain proof messages directly. The RegistryDirectory records each registry's anchoring chain and validates it against the DAO-governed supported chain list.
Our next step is connecting the Polygon and SUI testnets end-to-end: a registry on SUI publishing a proof that the Federation contract on Polygon receives, verifies, and makes available to the rest of the network. When that works — and we expect it to, because all the pieces are in place — Phase 7 is complete and the protocol is genuinely multi-chain.
After that, the path to production is a security audit, a mainnet deployment, and the first government registry willing to run a live pilot. We are working toward all three simultaneously.
The Bigger Picture
Multi-chain is not a technical novelty for us. It is a precondition for the protocol working at the scale we are building toward.
A land registry in Southeast Asia, a titling program in West Africa, a cadastral authority in South America — these institutions are not going to all agree on one blockchain. They should not have to. What they should be able to agree on is a shared protocol for trust: a common standard for what a verified land record looks like, who can issue one, and how it can be confirmed across borders.
Landblock is that standard. The multi-chain architecture is what makes it universal rather than parochial. And LayerZero is what makes it work without anyone having to be in charge of the connection.
Landblock is an open protocol for federated land registry verification. Technical documentation is at landblock.app/docs. ADR-0024 (Multi-Chain Architecture), ADR-0025 (Supported Chain Governance), and ADR-0026 (Primary Chain Designation) are available in the public documentation. To follow our progress or discuss a pilot, join the community on Slack or reach us at landblock.app/#contact.