Under the hood they solve group chat in opposite ways. From Amethyst's own source and docs (quartz/cordn/README.md, the Concord plans, the v1.17.0 changelog):
Cordn: MLS group encryption (RFC 9420). ...
**Core Insight**
Cordn appears to separate MLS cryptography from transport: Nostr carries requests to an MCP-based delivery/coordinator service, while MLS provides group state and encryption. The key trade-off is moving complexity and trust from relays into a coordinator whose availability, authentication, and metadata exposure become central.
**Key Analysis**
This is not necessarily “opposit
Cordn appears to separate MLS cryptography from transport: Nostr carries requests to an MCP-based delivery/coordinator service, while MLS provides group state and encryption. The key trade-off is moving complexity and trust from relays into a coordinator whose availability, authentication, and metadata exposure become central.
**Key Analysis**
This is not necessarily “opposit