Sahaay: Offline-First Emergency Mesh Network 🛜

Sahaay is a localized, offline-first tactical mesh network designed to maintain critical communication during internet blackouts and natural disasters.

The Architecture

Sahaay operates through a dual-interface system powered by a robust Go backend utilizing libp2p for decentralized peer discovery.

1. The Core Backend (Go + Libp2p)

• True Peer-to-Peer: Uses multi-address mDNS to discover and connect to local network nodes entirely without the internet.
• Event-Driven State: Operates on an atomic UIManager using buffered channels to guarantee thread-safe data synchronization.
• GraphQL APIs: Uses gqlgen to serve a high-performance local API over localhost for the UI to consume.
• Persistent Storage: Utilizes bbolt and sqlite to persist critical medical and SOS logs locally on the device.

2. The Tactical UI (Electron + React)

• Offline Capable: Packaged as a desktop application so first-responders don't require browsers or domains.
• Live System Monitoring: Interfaces directly with machine stats (Battery, Connectivity) to give operators a true tactical overview.
• Message Prioritization: Triage system ranging from Low to CRITICAL with visual alerting.

Tech Stack

• Backend: Go (1.24.6), Libp2p, GraphQL (99designs/gqlgen), BoltDB
• Frontend: React 19, Vite, Tailwind CSS, Lucide Icons, Leaflet (Mapping)
• Desktop Wrapper: Electron & Electron Builder

💻 Running it Locally

Prerequisites

• Go 1.24+
• Node.js & npm

Starting the Mesh Node

cd sahaay
go run main.go

Starting the Desktop Interface

cd sahaay-desktop
npm install
npm run dev

---

Built to keep people connected when they need it most.