Protocol implementers
Normative v1.0 spec, frozen test vectors, Python and Rust reference stacks, and an open certification program.
Your relay network is your pairing graph
Decentralised, social-relay, post-quantum messaging — from yakking
End-to-end encrypted messages move through mailboxes run by people you have pairwise paired with — not a central messaging platform or an open global relay pool.
How a message moves
Phones that cannot accept inbound connections poll outbound to paired relays. Relays validate protocol structure and limits but never see message plaintext.
flowchart LR Alice[Alice encrypts] --> Relay[Paired social relay] Relay --> Bob[Bob polls and decrypts] Relay -.->|opaque blob only| Relay
Social relays, not a global pool
Relay discovery and authorisation come from pairwise relationships and signed delivery profiles in your trust graph — the opposite of an open relay directory anyone can upload to.
flowchart TB
subgraph clients ["Clients - trusted with plaintext"]
A[Alice]
B[Bob]
end
subgraph relays ["Relays - untrusted for confidentiality"]
M["Mailbox relay<br/>Dave node"]
end
A -->|POST ciphertext| M
B -->|GET by mailbox tag| M
A -.->|signed invite / pairing| BYour pairing graph is your network
Each relationship brings relay URLs, TLS pins, and mailbox routes. Your reachable network grows with who you trust — homelab operators, friends, and community nodes.
flowchart TB You[Your device] --> R1[Relay: friend A] You --> R2[Relay: friend B] You --> R3[Relay: your homelab] R1 --> Net1[Alice, Carol, ...] R2 --> Net2[Bob, Dave, ...] R3 --> Net3[Family group]
Who Yakr is for
An open protocol and reference implementation — not a consumer messenger app.
Security reviewers
Threat models, negative vectors, hybrid PQ interop tests, and a blind external review package for independent auditors.
Homelab & community operators
Run mailbox relays for your circle. Pairwise trust means you are not opening a global upload endpoint to the internet.
Privacy-conscious groups
Families, clubs, and small orgs who want offline-tolerant E2E messaging without betting on one central provider.
Intended use cases
Circle messaging
A friend or family member runs a relay; everyone paired with them can send and receive asynchronously.
Homelab delivery
Store-and-forward through your own node when mobile clients cannot accept inbound HTTP.
Future messengers
Independent apps can implement Yakr; this repository defines the protocol, not a shipped product.
Research & interop
Post-quantum hybrid pairing, onion routing options, and cross-language conformance tooling.
Start on GitHub
Source, spec, security reporting, and contributions live in the open repository.
Repository
Normative spec
Run a relay
Report issues
From the blog
Updates on protocol design, homelab ops, and implementation progress.
Running a Yakr relay on your homelab
A practical intro to operating a mailbox relay for your circle — pairing, ports, and what relays actually see.
Welcome to yakr.co.uk
The Yakr Protocol site is now a proper marketing home, visual guide, and blog — built with Astro and deployed to the homelab.
What is social-relay messaging?
Why Yakr routes messages through pairwise-trusted relays instead of a central platform or open global relay pool.