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Architecture Overview

Understand how C3 keeps your code and data secure while enabling seamless mobile access.

How It Works

C3 creates a secure bridge between your mobile device and your development machine. When you send a message from the app, it travels directly to your computer where your AI coding agent processes it — no cloud intermediaries, no third-party servers storing your code.

Your PhoneC3 App
Encrypted Connection
Real-time sync
Your ComputerC3 Backend + AI Agent

Direct Connection

No middleman servers

You're In Control

Approve every action

Fully Encrypted

TLS for remote access

Your Code Never Leaves Your Machine

C3 runs entirely on your local machine. Your source code, project files, and conversation history stay on your computer. The only external connection is to your AI provider's API when your agent processes requests — the same as running the agent directly from your terminal.

Security First Design

C3 was built with security as the foundation, not an afterthought. Every feature is designed to protect your code and development environment.

Required Authentication

Every connection requires username and password authentication. There's no anonymous access — only authorized devices can connect to your backend.

Permission System

The agent can't execute file changes, run commands, or access sensitive operations without your explicit approval. You see exactly what's happening before it happens.

Isolated Sessions

Each project runs in its own isolated session. With Git Worktrees enabled, each session works on a separate branch, preventing conflicts and unintended changes.

Checkpoint & Rewind

Made a mistake? Every change is tracked with automatic checkpoints. Rewind to any previous state instantly — your code is always recoverable.

Authentication

C3 uses multiple layers of authentication to ensure only you can access your development environment.

Connection Authentication

When you start the C3 backend, you set a username and password. These credentials are required for any device to connect — without them, connection is refused.

How it works

  • • Credentials are set when starting the backend server
  • • The mobile app stores credentials securely in the device keychain
  • • Failed authentication attempts are logged and rate-limited
  • • Multiple failed attempts result in temporary IP blocking

Terminal Authentication

Terminal access uses the same authentication layer. When you open a terminal session from the app, it creates an authenticated connection to your machine's shell — no additional login required, but still fully secured.

Strong Password Recommended

For remote access, use a strong password (12+ characters with mixed case, numbers, and symbols). Change credentials periodically, especially if you suspect they may have been compromised.

Data Privacy

Your privacy is paramount. Here's exactly what data goes where:

Data TypeWhere It Goes
Source CodeStays on your machine — never sent to C3 servers
Chat MessagesYour machine → AI provider API (same as CLI)
Session HistoryStored locally on your machine
CredentialsEncrypted in device keychain (never transmitted)

AI Provider API Usage

When your agent processes requests, it uses the respective provider's API — the same as running the agent directly from your terminal. Review your provider's privacy policy (e.g., Anthropic, OpenAI) to understand how your prompts are handled.

Connection Security

How your connection is secured depends on your setup:

Local Network

  • Direct connection over your WiFi
  • Traffic never leaves your network
  • Authentication still required

Remote Access (ngrok)

  • TLS/SSL encryption (HTTPS)
  • End-to-end encrypted tunnel
  • Authentication + encryption combined

Rate Limiting & Protection

C3 includes built-in protection against unauthorized access:

  • Rate limiting — Prevents brute-force attacks on credentials
  • IP blocking — Temporarily blocks IPs after multiple failed attempts
  • Connection logging — All connection attempts are logged for review

Public WiFi Caution

When using C3 on public WiFi (coffee shops, airports), always use remote access with ngrok enabled. This ensures your traffic is encrypted even on untrusted networks. Consider using a VPN for additional protection.