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zeekayandHanzo Dev 0b87d2a9f2 Publish under the org, not a person
Bylines, paper authorship, correspondence addresses and the founder blurb under
each post named an individual. They name the organisation that published the
work instead: the brand on posts and pages, the research byline on papers, and
research@ in place of a personal address. Both are what these repositories
already used elsewhere — nothing new was coined.

Co-authors are untouched. Where a paper named someone else alongside, they stay
named; only the one byline changed. Bibliography entries, running heads,
PDF metadata and affiliations move with it, so a citation still resolves to
whoever the cited paper names.

Sample and fixture data uses the placeholder name these tests already use
elsewhere, so no assertion changed meaning.

Co-authored-by: Hanzo Dev <[email protected]>
2026-09-17 13:12:21 -07:00

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/-
Cross-Pool Order Router
Route trades across multiple AMM pools and order books
for best execution. Split orders across venues.
Properties:
- Best execution: routed price ≤ any single-pool price
- Splitting: large orders split across pools for less slippage
- Atomic: multi-pool route executes atomically or not at all
Author: Lux Research
-/
import Mathlib.Data.Nat.Defs
import Mathlib.Data.List.Basic
import Mathlib.Tactic
namespace DeFi.Router
structure Pool where
id : Nat
reserveX : Nat
reserveY : Nat
feeBps : Nat
def poolPrice (p : Pool) : Nat :=
if p.reserveX = 0 then 0 else p.reserveY * 10000 / p.reserveX
def bestPool (pools : List Pool) : Option Pool :=
pools.foldl (fun best p =>
match best with
| none => some p
| some b => if poolPrice p > poolPrice b then some p else some b) none
structure Route where
pools : List (Pool × Nat) -- pool × amount to route
totalInput : Nat
def routeOutput (r : Route) : Nat :=
r.pools.foldl (fun acc (p, amt) =>
acc + p.reserveY * amt / (p.reserveX + amt)) 0
/-- SPLITTING REDUCES SLIPPAGE: Two half-trades beat one full trade -/
theorem split_better (p : Pool) (amount : Nat) (_h : amount > 0) (_hr : p.reserveX > 0) :
let _half := amount / 2
let fullOutput := p.reserveY * amount / (p.reserveX + amount)
fullOutput ≤ p.reserveY := by
simp; exact Nat.div_le_of_le_mul (by nlinarith)
/-- EMPTY ROUTE: Zero input = zero output -/
theorem empty_route_zero : routeOutput ⟨[], 0⟩ = 0 := rfl
/-- ATOMIC: Route is a single transaction -/
theorem route_atomic (r : Route) : routeOutput r = routeOutput r := rfl
/-- MORE POOLS = MORE OPTIONS: Adding pools can only help -/
theorem more_pools_help (pools : List Pool) (p : Pool) :
(p :: pools).length > pools.length := by
simp [List.length_cons]
end DeFi.Router