defi-primitives

A lightweight Rust crate modeling core DeFi primitives: assets and liquidity pools based on the constant product formula (x·y=k).

Warning

Built as a learning exercise toward DeFi development. Not production-ready.

What's included

• Asset — native tokens, ERC20/SPL tokens, and recursive LP tokens
• Pool — liquidity pool with two assets and position tracking
• Pool::quote() — AMM output calculation using the x·y=k invariant
• Pool::constant_product() — returns k for a given pool state

The math

Given a pool with reserves x and y, the invariant k is:

k = x · y

For a trade of amount_in:

amount_out = y · amount_in / (x + amount_in)

Usage

let pool = Pool { ... };
let out = pool.quote(1_000, &pool.asset_a);

Roadmap

• Position management (deposit, withdraw)
• Fee calculation
• Multi-hop routing

Author

Marco Kergeist - marcokergeist@proton.me