Files
proofs/lean/Build/Coeffect.lean
zooqueenandHanzo Dev d3bff5e2dc proofs: drive Lean library to 0 errors, eliminate proof-by-assumption axioms
The lean/ proof library (88 files) had ~180 type-check errors across ~45 files
plus 31 proof-by-assumption axiom cheats. It now type-checks cleanly under
Lean 4.14.0 + Mathlib, with every theorem genuinely proven from definitions.

Errors fixed:
- Stale Mathlib imports: Data.Nat.Basic / Data.Int.Basic were removed this rev
  -> Data.Nat.Defs / Data.Int.Defs (57 files).
- Shared AI/Agent/Governance/Contract/DeFi/Ecology draft files: same proof-rot
  as the zoo-labs sibling library (now reconciled): omega missing in-scope
  bounds, dead tactics after simp, simp over-reduction, doc-comment placement,
  reserved-word binders, deriving Repr on Finset-bearing structs, noncomputable
  defs over opaque primitives.
- Consensus/Liveness: collapsed a 74-error cascade (undefined shared state model
  inlined from Safety.lean; the |>. pipe-projection vs comparison parse trap on
  14 lines rewritten to explicit dot projection).
- Crypto (BLS/FROST/Corona/Hybrid/threshold/FHE), Consensus, Protocol, Warp,
  Trust, GPU, Compute, Network, DeFi: brought structure invariants into scope
  for omega, Nat-division bounds via Nat.div_le_of_le_mul / Nat.div_mul_le_self,
  noncomputable over opaque crypto ops, deriving Inhabited for index access.

Integrity:
- Removed all 31 `theorem X := X_ax` cheats (axiom asserting the identical
  statement) and proved each from definitions; removed the UNSOUND
  content_addressed axiom (hash-injectivity over a struct with free fields).
- Quorum-intersection theorems (BFT/Quasar/Flare/Warp/BLS/GPU/Bridge): the draft
  hypothesis 3f<n is insufficient (n unbounded above makes them false); tightened
  to the optimal-resilience invariant n=3f+1 / 2t>n. Statement intent preserved.
- Net axiom change: -35 / +1 (the one addition, honesty_static, is a
  fixed-validator-set modeling assumption matching sibling files).
- Remaining axioms are trusted-base only: opaque crypto primitives (groups,
  pairings, hardness, hashes, FHE encrypt/decrypt, BLS soundness, forward
  secrecy, Fisher-Yates uniformity) and protocol modeling assumptions. No
  sorry/admit/native_decide. Verified all theorems trace to
  [propext, Classical.choice, Quot.sound] plus those primitives.

Co-authored-by: Hanzo Dev <[email protected]>
2026-06-02 05:54:28 -07:00

120 lines
4.1 KiB
Lean4

/-
Authors: Antje Worring, Zach Kelling
Coeffect Algebra
Effects: what a computation DOES to the world.
Coeffects: what a computation NEEDS from the world.
A pure build needs nothing external (coeffects = ∅).
An impure build needs time, random, network, filesystem, etc.
The tensor product (⊗ = append) combines coeffects.
Maps to:
- hanzo/runtime: sandbox coeffect tracking
- hanzo/attest: discharge proof generation
- lux/node: build reproducibility checking
Properties:
- Pure is identity for tensor
- Tensor is associative
- Pure ⊗ pure = pure
- Time and random are non-reproducible
-/
import Mathlib.Data.Nat.Defs
import Mathlib.Data.List.Basic
import Mathlib.Tactic
namespace Build.Coeffect
/-- What a build needs from the world -/
inductive Coeffect where
| pure -- Needs nothing
| filesystem (path : String) -- Non-CA file access
| filesystemCA (hash : Nat) -- Content-addressed file
| network (host : String) -- Non-CA network
| networkCA (hash : Nat) -- Content-addressed network
| time -- Wall clock (non-reproducible)
| random -- Entropy (non-reproducible)
| gpu (device : String) -- GPU access (non-deterministic)
| auth (provider : String) -- Credential access (ephemeral)
| tee (attestation : Nat) -- TEE hardware attestation
deriving DecidableEq, Repr
/-- A coeffect set (tensor = append) -/
abbrev Coeffects := List Coeffect
/-- Pure coeffect set (empty = needs nothing) -/
def Coeffects.pure : Coeffects := []
/-- Check if coeffects are pure -/
def Coeffects.isPure (r : Coeffects) : Bool := r.isEmpty
/-- Check if coeffects allow reproducible builds -/
def Coeffects.isReproducible (r : Coeffects) : Bool :=
r.all fun c => match c with
| .pure | .filesystemCA _ | .networkCA _ | .tee _ => true
| .time | .random | .gpu _ | .auth _ => false
| .filesystem _ | .network _ => false
-- ═══════════════════════════════════════════════════════════════
-- THEOREMS
-- ═══════════════════════════════════════════════════════════════
/-- Empty coeffects are pure -/
theorem empty_is_pure : Coeffects.isPure [] = true := rfl
/-- Pure coeffects are reproducible -/
theorem pure_is_reproducible : Coeffects.isReproducible [] = true := rfl
/-- Tensor with pure is identity (right) -/
theorem tensor_pure_right (r : Coeffects) : r ++ [] = r :=
List.append_nil r
/-- Tensor with pure is identity (left) -/
theorem tensor_pure_left (r : Coeffects) : [] ++ r = r := rfl
/-- Tensor is associative -/
theorem tensor_assoc (a b c : Coeffects) : (a ++ b) ++ c = a ++ (b ++ c) :=
List.append_assoc a b c
/-- Pure ⊗ pure = pure -/
theorem tensor_pure_pure (a b : Coeffects)
(ha : a.isPure) (hb : b.isPure) : (a ++ b).isPure := by
simp [Coeffects.isPure, List.isEmpty_iff] at *
simp [ha, hb]
/-- Reproducible ⊗ reproducible = reproducible -/
theorem tensor_reproducible (a b : Coeffects)
(ha : a.isReproducible) (hb : b.isReproducible) :
(a ++ b).isReproducible := by
simp only [Coeffects.isReproducible, List.all_append, Bool.and_eq_true]
exact ⟨ha, hb⟩
/-- Time is not reproducible -/
theorem time_not_reproducible :
Coeffects.isReproducible [.time] = false := rfl
/-- Random is not reproducible -/
theorem random_not_reproducible :
Coeffects.isReproducible [.random] = false := rfl
/-- GPU is not reproducible -/
theorem gpu_not_reproducible (d : String) :
Coeffects.isReproducible [.gpu d] = false := rfl
/-- Auth is not reproducible -/
theorem auth_not_reproducible (p : String) :
Coeffects.isReproducible [.auth p] = false := rfl
/-- Content-addressed filesystem IS reproducible -/
theorem ca_filesystem_reproducible (h : Nat) :
Coeffects.isReproducible [.filesystemCA h] = true := rfl
/-- TEE attestation IS reproducible -/
theorem tee_reproducible (a : Nat) :
Coeffects.isReproducible [.tee a] = true := rfl
end Build.Coeffect