# Introducing Phage <!-- .slide: data-background="https://hackmd.io/_uploads/S1PanyS62.png" --> ## Programmable Transaction Middleware for Ethereum Nodes --- ## Phage is a rust based library that provides programmable transaction middleware for Ethereum nodes --- ### Current transaction broadcasting infrastructure is passive  --- ### Existing protection tools are concentrated on the wallet layer  --- ## Phage modules enable nodes to make automated decisions  --- ## With Phage you can build... ✅ Custom RPC methods ✅ Intelligent transaction routing ✅ Real time threat interception ✅ Invisible policy enforcement & alerting --- ## Build modules in 3 steps ### Define the services ### Define the rules ### Install on your node --- ### Modules contain hooks for external services  --- <!-- .slide: data-background="https://hackmd.io/_uploads/ryULj1Ha3.png" data-background-color="#005" --> ## Rules are defined using Banyan ### The declarative policy language for modules based on Cedar by AWS  --- <!-- .slide: data-background="https://hackmd.io/_uploads/ryULj1Ha3.png" data-background-color="#005" --> ## Define transaction rules based on decoded & enriched transaction data ``` javascript [1|3|4-8|9] @name("WARN-NATIVE-ASSET-THRESHOLD") @advice("Warn when sending funds over X threshold") @notification("WEBHOOK-e03a0aa1") forbid ( principal, action == Action::"EOATransaction", resource ) when { context.value.u256GreaterThan(principal.valueLimit) }; ``` --- ### Use modules to dynamically route & bundle transactions  --- ### Enrich MPC transaction services with policies & detailed context  --- ### Intercept threats with external datasets & AI models  --- ## Read More * https://hackmd.io/@shield3/intro-phage * https://github.com/ipatka/banyan * Twitter: @isaacpatka