ENGINEERING CASE STUDY / 001
One office cabin.
A complete income cycle.
A fictional asset made the tokenization workflow tangible: define an income right, issue units, enroll an investor, record net rent, allocate credits, and claim a payment.
Educational prototype · Sepolia testnet · Fake assetsThe question we explored
How can an operator and an investor follow the same rental-income record, with clear balances and an explicit allocation rule? We used a fictional 120 sq ft, four-seat office cabin, A–101. The prototype demonstrates accounting and transaction mechanics; it does not establish property ownership or an enforceable claim to a real cabin.
The defined demo right is a proportional share of simulated distributable rent. There are 1,000 CAB units. The operator initially holds all of them, and each CAB costs $100 USD in the primary purchase flow.
One illustrative November
| Item | Example | What it means |
|---|---|---|
| Fixed CAB supply | 1,000 | All units start with the operator |
| Investor purchase | 100 CAB | 10% participation, costing $10,000 USD |
| Collected rent | $30,000 USD | Declared by the operator |
| Expenses / reserve | 5,000 / 0 | Deducted before allocation |
| Distributable net | $25,000 USD | Funded into the demo contract |
| Investor allocation | $2,500 USD | 10% of net rent |
| Operator allocation | $22,500 USD | The remaining 900 CAB also earn rent |
Participation is measured when the rent record transaction executes. A purchase after that transaction does not receive that period’s allocation. Already allocated credits remain with their recipient after a later CAB transfer.
Three ways to follow the workflow
- Browser walkthrough: a self-contained simulation, with editable purchase size and rent inputs. No wallet, shared backend or blockchain transaction. Every visitor gets an independent cycle.
- Local development lab: a Hardhat development chain with scripted test accounts, used for repeatable engineering checks. This developer server is not exposed by this website.
- Sepolia wallet lab: a static frontend using ethers and the visitor’s injected wallet. Transactions are signed in that wallet and submitted to Sepolia. Deploy a separate pilot, or open a known pilot by its CAB address.
Try the browser walkthrough ↗ · Open the Sepolia wallet lab ↗
What the prototype implements
- Two contracts: a demo USD token with a once-per-address faucet, and a fixed-supply CAB contract with purchases, transfers, rental accounting and claims.
- Self-enrollment before receiving CAB. A maximum of 20 participants bounds the allocation loop. Enrollment is a demo mechanism, not identity verification or KYC.
- The operator funds net rent; gross rent, expenses and reserve are recorded for the period. A period identifier can be recorded only once.
- Integer accounting at two decimal places for demo USD. Allocation rounds down, and the contract carries the residual forward for a later distribution. The short browser walkthrough stops after one cycle.
- Exact-amount spending approvals when needed. Approval and purchase, or approval and rent recording, are separate wallet transactions.
- Chain, wallet and deployed-code checks before writes; pending and confirmed states; explorer receipts; protections against continuing an interface flow after an account or network change.
The operator supplies the income figures. No contract can infer from this demo whether a real tenant paid rent or whether an expense is valid.
Evidence you can inspect
The Sepolia prototype was deployed and exercised with separate operator and investor accounts. The linked historical purchase exchanged 10,000 legacy demo-currency units for 100 CAB. The current demonstration uses simulated USD. Historical contracts retain their original currency metadata; the linked transaction is not a USD payment or currency conversion. This proves that transaction’s testnet execution, not real asset backing, legal rights, or ongoing system availability.
- Historical CAB prototype contract on Sepolia ↗
- Historical demo-currency contract on Sepolia ↗
- 100 CAB purchase transaction ↗
The prototype’s automated suite passed 21 checks covering contract accounting, API behavior, wallet guards and the Sepolia interface using a simulated wallet against a local chain. These checks are engineering evidence, not an independent smart-contract audit. The browser walkthrough has separate checks for allocation, input validation and duplicate-claim prevention.
What a real asset launch still needs
This code is a starting point for discovery and a testnet pilot. It is unaudited and is not ready to hold real funds. A production scope depends on the asset, jurisdiction, participants and intended right.
| Workstream | Required decisions and evidence |
|---|---|
| Asset and rights | Verify ownership or leasing authority; define the issuer, enforceable claim, deductions, default handling and investor agreements with qualified local counsel. |
| Participants and custody | Determine applicable onboarding, identity and transfer restrictions; choose custody, key recovery and participant support arrangements. |
| Contract security | Design permissions, emergency controls and key management; test invariants and failure cases; arrange independent review and remediate findings before real value is introduced. |
| Accounting and payments | Reconcile actual receipts and expenses to distributions; define approval controls, corrections, disputes, reporting and the permitted settlement asset. Replace the free demo faucet. |
| Scale and reliability | Replace the 20-holder allocation design for the intended scale. Implement durable transaction tracking, event indexing, reorganization handling, RPC fallback, monitoring and incident procedures. |
| Release operations | Separate environments, review deployments, manage infrastructure access, test recovery, document support ownership and maintain a security response process. |
A mainnet deployment alone does not complete these workstreams. Token ownership also does not guarantee liquidity or rental income.
A focused first engagement
Start with a bounded discovery: one asset type, one defined right, one jurisdiction and one participant journey. Deliver a pilot blueprint with assumptions and acceptance criteria, then implement a testnet workflow and handover. Use the pilot evidence to scope the legal, security, accounting and operational work for a subsequent production phase.
Suziyan’s engineering work can cover contracts, operator and investor interfaces, integration design, testnet deployment, automated checks and technical handover. Legal advice and independent security audits require the appropriate specialists.
Background and security reading
BlackRock: What is tokenisation?
World Economic Forum: What is tokenization?
Ethereum: smart contract security
OWASP Smart Contract Top 10
Have an asset workflow in mind?
Send the asset type, location, intended token right and business outcome.
contact@suziyan.in ↗