Radix vs Polkadot

Overview

Both Radix and Polkadot address scalability through sharding, but with very different architectures:

Sharding Model

Polkadot uses a hub-and-spoke model: parachains (application-specific shards) connect to a relay chain that provides shared security. Parachain slots are limited and auctioned — creating artificial scarcity.

Radix uses Cerberus with effectively unlimited shards. Consensus is braided dynamically per-transaction across relevant shards — no slot auctions, no capacity limits.

Composability

Polkadot's XCM (Cross-Consensus Messaging) enables cross-parachain communication, but it's asynchronous. Radix provides atomic composability across all shards — critical for DeFi where partial execution can mean lost funds.