Arc carries the pool. Circle’s Layer 1 went live on 16 September 2026. It is EVM-compatible, uses USDC as its native gas token, and settles in under a second. Receivables, tranche tokens, the loss waterfall and the first-loss floor all live here.

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The reason that actually decided it

Arc was chosen because a credit pool needs fiat at both ends. Circle Mint and the institutional rails are native to it, and its validator set is made up of the institutions most likely to buy senior notes. That second point is the one worth sitting with. The senior layer is the largest and the cheapest, so the cost of the whole pool depends most on who will hold it. Being on a chain those buyers already validate is a distribution advantage, not a technical one.

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What lives on Arc

  • Receivable records and repayment routing
  • The three tranche tokens
  • The loss waterfall
  • The first-loss floor and ratio caps
  • Per-pool state and isolation
The full list, and what is deliberately excluded, is in contract mechanics in version one.