Best-execution routing

Best-execution routing is Matura's core differentiator. Rather than funding a claim from a single vault at a single price, the router finds the cheapest verifiable combination of vault legs and proves that choice is honored on-chain.

The objective

Given a claim (or slice) and the set of eligible vaults, choose the allocation of legs that minimizes the cost to the beneficiary (maximizes what they receive), subject to each vault's mandate, available capital, and reservations. The optimizer is a pure integer routine in @matura/shared — a bounded exact search with a greedy fallback — so results are deterministic and reproducible.

Determinism and the mirror

The decisive property is that the off-chain choice is re-validated on-chain before any funds move:

• The API validates each leg against a pinned block through one shared off-chain _validateLegs mirror (common/leg-mirror.ts), so the API and the contract agree by construction.
• It persists a single-use RouteIntent and emits the signable ExecutionRoute.
• On submission, MaturaRouter.executeRoute recomputes and re-checks the legs on-chain; if the world moved (price, liquidity, expiry), execution reverts rather than filling a stale route.

The flow

optimize  →  review  →  sign (EIP-712)  →  submit (executeRoute)  →  index

One coerced message is the single source of truth: the same payload feeds the signature, the on-chain hash, and executeRoute. Targets are pinned to the deployment manifest, and money crosses the signing boundary as BigInt(str) base units — never floats.

Why it matters

A route you can't verify is just a quote you have to trust. Matura's router makes the cheapest option checkable: deterministic selection off-chain, exact re-validation on-chain, single-use intents.

Full design, constraints, and the isBetter comparator are in the mirrored routing reference; the signable endpoints are in API › Best-execution routing.