Module grumpkin 

Minimal Grumpkin curve arithmetic for contract address derivation.

Grumpkin is an embedded curve of BN254 defined by y^2 = x^3 - 17 over BN254’s scalar field (Fr). Only affine point addition and scalar multiplication are implemented — just enough for compute_contract_address_from_instance.

Functions

generator

Return the Grumpkin generator point G = (1, y) where y = sqrt(1 - 17).

has_positive_y

Returns whether the affine point uses Aztec’s canonical “positive” y-coordinate.

point_add

Add two Grumpkin affine points.

point_from_x

Recover the canonical Grumpkin affine point from an x-coordinate.

scalar_mul

Scalar multiplication via double-and-add.