Inside Project Acacia: our read on the RBA × DFCRC final reportacacia.rem.money
Case Study · 01

A tokenised corporate bond on a private Zone.

Investors settle the primary in USDC and receive notes registered directly on the Zone. Fixed coupons pay out in USDC on schedule, principal redeems at par at maturity, and balances are private to other participants. Qualified-investor compliance lives at the protocol layer, not in your contract. This is the reference architecture REM ships, and it is built to survive a regulator's walkthrough.

TIP-403
Compliance enforcement
DvP
Primary settlement
Same-day
Coupon payment
View-keyed
Auditor access
The Product

In one sentence.

USDC in at primary settlement, fixed-coupon CORPBOND notes out. Coupons pay on schedule, principal redeems at par at maturity, and the notes only ever move between allow-listed qualified investors. The selling restrictions live at the protocol layer. Not in your contract, not skippable, and updateable within one block of a sanctions list change.

Cast of Characters

The six parties that make it work.

A tokenised bond is more than a smart contract. Six counterparties co-operate, and knowing where each one sits (on-chain or off) is the first design decision.

Issuer / Corporate Treasury

Sells the notes and services the debt. Holds the master operator key for the Zone and prefunds every coupon.

Lead Arranger / Dealer

Structures the deal, runs the bookbuild, and allocates the primary. A regulated investment bank or debt-capital-markets desk.

Trustee & Paying Agent

The trustee represents noteholders and enforces covenants. The paying and calculation agents fix and pay each coupon — on a Zone, mostly contracts plus a signing key.

Investors

KYC'd qualified investors seeking fixed income without public-chain exposure.

Auditor / Regulator

View-key access for compliance audits. Read-only, scoped, revocable.

REM

Designs the Zone, ships the contracts, operates infra. Cannot touch investor funds or the issuer's proceeds.

Technological Roadmap

How the rail comes online.

Seven phases across two parallel tracks. The legal and deal scaffolding gates production launch; the on-chain build gates the technical milestones. Every phase is a discrete deliverable with sign-off criteria.

  1. Phase 00
    Legal & deal scaffolding
    Off-chain
    • ›Choose the legal form: a digitally native registered note under a DLT-securities framework (UK Digital Securities Sandbox, Germany's eWpG, Luxembourg's DLT laws, Japan's security-token regime), or a conventional global note mirrored on-chain.
    • ›Draft the deal documents: offering memorandum, trust deed or indenture, agency agreements, and the selling restrictions for each target jurisdiction.
    • ›Mandate the lead arranger, engage a rating agency if the issue is rated, and fix the term sheet: 5.25% semi-annual, 30/360 day count, five-year bullet.
    • ›Select the KYC/KYB vendor (Persona, Jumio, Sumsub), codify the qualified-investor policy, and build the onboarding portal: identity verification, subscription documents, allow-listed wallets.
  2. Phase 01
    Stand up the Zone
    On-chain
    • ›Generate the sequencer key set, deploy the Zone portal on Tempo, initialise genesis.
    • ›Provision per-environment chain IDs (testnet, staging, production) with isolated keys.
    • ›Mirror the TIP-403 compliance policy from Tempo L1, replicated continuously to the Zone.
    • ›Wire observability: block explorer, sequencer health, compliance event stream, on-call paging.
    $rem zone deploy --network tempo --policy corp-bond
  3. Phase 02
    Configure the qualified-investor policy
    On-chain
    • ›Author TIP-403 policy CORPBOND_QUALIFIED_INVESTORS on Tempo L1 with the deal's jurisdictional selling restrictions baked in.
    • ›Wire the KYC vendor's webhook to push approved wallet addresses into the policy.
    • ›Plug in screening providers (Chainalysis, TRM) for ongoing wallet risk scoring and de-listing.
    • ›Validate at the protocol layer: non-allow-listed wallets cannot hold, send, or receive the notes — primary or secondary.
    $rem compliance policy.create('CORPBOND_QUALIFIED_INVESTORS')
  4. Phase 03
    Issue the note token
    On-chain
    • ›Mint the note token through the Zone's TIP-20 factory: 1,000-unit par denomination, supply fixed at the issue size, ISIN carried in token metadata.
    • ›Bind the qualified-investor TIP-403 policy as the immutable transfer hook.
    • ›Set the mint authority to the IssuanceController address; lock the upgrade path behind a multi-sig.
    • ›Pre-flight with an external audit firm before the primary settles.
    $rem zone tokens.issue({ symbol: 'CORPBOND', policy: 'CORPBOND_QI' })
  5. Phase 04
    Build the bond contract suite
    On-chain
    • ›IssuanceController: DvP primary settlement — notes mint only against USDC received, with a refund path on policy failure.
    • ›CouponAgent: record-date snapshots, 30/360 coupon fixings, issuer prefunding, pro-rata distribution with a claims fallback.
    • ›MaturityAgent: par redemption at maturity, plus an optional issuer call with make-whole pricing.
    • ›SubscribeFromTempo: one-shot L1 on-ramp, encrypted subscriptions, refund path on policy failure.
    • ›Full test coverage, invariant fuzzing, and an external auditor's report against the production tag.
    $forge build && forge test --gas-report
  6. Phase 05
    Wire the coupon operating model
    Hybrid
    • ›Codify the coupon calendar on-chain; the calculation agent signs each fixing before it is accepted.
    • ›Issuer prefunds the CouponAgent ahead of each payment date; every holder is paid the same day, with no agent chain in between.
    • ›Treasury operations dashboard streams Zone events into back-office and the trustee's and auditor's view-keyed feeds.
    • ›Incident playbooks for missed prefunding (grace-period mechanics), screening hits, and acceleration on default.
  7. Phase 06
    End-to-end programme rehearsal
    On-chain
    • ›Full lifecycle run by test wallets: primary DvP, coupon fixing and payment, secondary transfer between allow-listed wallets, maturity redemption at par.
    • ›A simulated coupon period confirms the 30/360 accrual math against the calculation agent's shadow book.
    • ›Auditor view-keys issued, scoped, exercised, and revoked. Compliance event log signed and archived.
    • ›Issuer, arranger, and regulator walkthroughs of the live testnet environment, pre-launch.
The Contract Suite

Four contracts. That is the whole programme.

The Zone supplies the heavy machinery: the TIP-20 token factory, sequencing, compliance enforcement, and cryptographic settlement to Tempo L1. The contracts only encode the deal-specific terms: primary settlement, coupons, and redemption. Every contract ships with full test coverage, invariant fuzzing, and an external auditor's report.

IssuanceController.solPrimary Market

DvP settlement of the primary. Notes mint only against USDC received, allocations follow the arranger's book, and any subscription that fails the policy check refunds automatically.

subscribe(uint256 usdcAmount)allot(address investor, uint256 units)refund(bytes32 id)
CouponAgent.solCoupons

The paying-agent function as a contract. Record-date snapshots, deterministic 30/360 coupon fixings signed by the calculation agent, issuer prefunding, and same-day pro-rata distribution with a claims fallback.

fixCoupon(uint32 period)fund(uint32 period, uint256 amount)claim(uint32 period)
MaturityAgent.solRedemption

Principal repayment engine. Burns notes against a par-plus-final-coupon USDC payout at maturity, and supports an optional issuer call with make-whole pricing for callable structures.

redeem(uint256 units)callNotes(uint64 date, uint256 price)
SubscribeFromTempo.solL1 Bridge

One-transaction on-ramp from Tempo L1 into the Zone. Encrypted subscription payloads, policy pre-check, automatic refund on compliance failure.

subscribeFromMainnet(addr, usdc, bytes proof)refund(bytes32 id)
End-to-End Flow

One test wallet, twelve lines.

The full lifecycle — primary, coupon, secondary transfer, maturity — reproduces every time. This is exactly what an issuer or regulator sees in the demo.

zone://corp-bond/testnet
01Alice → IssuanceController.subscribe(100,000 USDC)02↳ TIP-403 policy check: Alice ∈ CORPBOND_QUALIFIED_INVESTORS ✓03↳ DvP: 100,000 USDC ⇄ 100 CORPBOND notes (1,000 par) at issue price 100.0004↳ Alice's balance: 100 CORPBOND (private)05// 6 months pass — first coupon date (5.25% s.a., 30/360)06Issuer → CouponAgent.fund(period 1)07↳ Fixing: 26.25 USDC per note → Alice receives 2,625 USDC same day08Alice → CORPBOND.transfer(Bob, 40)09↳ Policy check: Bob ∈ CORPBOND_QUALIFIED_INVESTORS ✓ — register updated atomically10// at maturity — final coupon + principal11Alice → MaturityAgent.redeem(60)12↳ Burn 60 CORPBOND, pay 61,575 USDC. Settlement finalised in the next Zone→Tempo batch (<60s)
The Build Split

The Zone replaces ~30% of the lift.

A bond issue always has a legal and deal layer that lives off-chain. The Zone collapses the bespoke infra build — the register, privacy, compliance enforcement, settlement — into a managed primitive. Most of what remains is the documentation and distribution work you would do for any debt issue.

On-chain · REM ships
  • Zone deployment and sequencing
  • TIP-403 selling restrictions enforced at the token layer
  • The noteholder register: primary DvP, secondary transfers, coupon distribution
  • Settlement back to Tempo L1 in cryptographic batches
  • Trustee and auditor view keys and event log integrity
Off-chain · You ship
  • Deal documentation: offering memorandum, trust deed, agency agreements
  • Governing-law election and the DLT-register framework
  • Credit rating, bookbuild, and investor marketing
  • KYC and qualified-investor onboarding
  • The issuer's covenants and use of proceeds
Economics

Where the savings come from.

The technology stack is the easy half of the savings story. The hard half is the operating model. A Zone-native bond collapses the four servicing-cost lines that dominate a conventional debt programme: the registrar, the paying-agent chain, per-transfer compliance, and investor servicing.

Registrar & transfer agent

The Zone is the register

No separate registrar, no transfer agent, no immobilised global note sitting in a vault. Where the legal framework recognises a DLT register, the token ledger is the register of noteholders, and every transfer updates it atomically. The reconciliation between registrar, clearing system, and custodian records disappears because there is only one record.

Paying-agent ops

Coupons without the agent chain

A conventional coupon hops from the issuer to the paying agent to the clearing system to custodians to beneficial owners, and takes days end to end. Here the issuer prefunds the CouponAgent once per payment date and every holder is paid the same day. The fixing is deterministic, signed, and verifiable on-chain.

Compliance ops

Selling restrictions enforced at the protocol

Qualified-investor checks happen once at onboarding, and the policy travels with the note. Per-transfer compliance review goes away, and so does the risk of a secondary trade breaching the deal's selling restrictions — a non-allow-listed wallet cannot hold the notes at all.

Investor servicing

Self-service corporate actions

Position statements come straight from the explorer. Coupon claims and maturity redemption are self-service against the contracts. The corporate-actions desk, the payment-instruction files, and the trustee-versus-registrar position breaks are all gone.

The Credibility Milestone

An investor-ready demo before the lawyers finish drafting.

The on-chain rail can come up before the deal documents are signed. You can show an issuer's board, an arranger, or a regulator a working testnet environment without the offering memorandum in place. The primary settles DvP, the coupon fixes and pays, a secondary transfer clears between allow-listed wallets, maturity redeems at par, and compliance fires at every hop. The slide deck becomes a walkthrough, and the credibility loop closes in days instead of quarters.

Ship this with REM.

This is the architecture REM builds for issuers and arrangers bringing debt programmes on-chain. Bring us your term sheet and your compliance constraints. We'll stand up the rail.

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