rchat
LAN-based terminal chat app in Rust with async TCP networking, private messages, and server-controlled identity.
Timeline
1 Week
Role
Backend / Systems Developer
Team
Solo
Status
CompletedTechnology Stack
Key Challenges
- Managing concurrent client sessions without shared-state race conditions
- Designing a clean text protocol while keeping messages human-readable
- Implementing private messaging and user discovery with predictable behavior
- Keeping terminal output structured when multiple events arrive rapidly
Key Learnings
- Actor-style architecture with Tokio channels and task isolation
- Reliable client lifecycle handling in TCP chat systems
- Identity enforcement at the server layer to prevent spoofing
- How to build practical networking tools with minimal dependencies
rchat: Async LAN Chat in Rust
Overview
rchat is a lightweight terminal chat system for local networks. It is composed of a Rust server and client binaries connected over asynchronous TCP.
The main goal was to build a robust chat architecture with clear message routing and practical command support while keeping the user experience simple in terminal environments.
Key Capabilities
- LAN multi-user chat over TCP
- Server-controlled identity in
username@ipformat - Private messaging with
/pm - Connected user listing with
/who - Clean disconnect flow via
/quitor/exit
Architecture Notes
Hub-Centric Routing
The server uses a central hub task to manage clients and broadcast logic. This follows an actor-like approach where state is owned in one place and communication happens through channels.
Dedicated Per-Client Tasks
Each client connection has isolated async tasks for I/O handling. This reduces coupling and improves fault boundaries when one client disconnects unexpectedly.
JSON Message Protocol
Messages are serialized in JSON with type, sender, content, and timestamp fields. This keeps protocol evolution straightforward and debuggable.
Security Tradeoffs
rchat intentionally prioritizes local-network simplicity:
- No TLS by default
- No user authentication layer
- Not intended for internet exposure
The server still enforces identity structure to block trivial impersonation from client-supplied payloads.
What This Project Demonstrates
rchat shows strong systems fundamentals in a compact codebase:
- Async concurrency with Tokio
- Protocol-oriented communication
- Separation of concerns between routing, transport, and client UX
It is a solid foundation for future enhancements such as authentication, encryption, persistence, and moderated channels.