System Architecture

System Overview

December is engineered as a hybrid terminal and cloud software development platform. It consists of four distinct architectural layers:

┌─────────────────────────────────────────────────────────────┐
│                       December CLI                          │
│         Local Filesystem · Native Bash · Git Trees          │
└──────────────────────────────┬──────────────────────────────┘
                               │
                        [/handoff sync]
                               ▼
┌─────────────────────────────────────────────────────────────┐
│                      December Cloud                         │
│       Session State · Artifact Storage · Auth Cookies       │
└──────────────────────────────┬──────────────────────────────┘
                               │
                 [Zero-Config Sandbox Provisioning]
                               ▼
┌─────────────────────────────────────────────────────────────┐
│                 Isolated Micro-VM Sandboxes                 │
│      Root Linux Environment · Node / Bun / Python Runtimes  │
│                  Live Web Preview Ports (Vite)              │
└─────────────────────────────────────────────────────────────┘

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The Dual-Surface Bridge

1. Local Terminal Agent: Operates with native file read/write permissions inside your repository clone. When given instructions, it inspects directory structures, analyzes dependency graphs, and runs compilation tests.
2. Cloud Handoff (/handoff): Serializes uncommitted modifications, git state, and conversation traces into an encrypted archive, transferring execution seamlessly to app.trydecember.com.
3. Web IDE & Sandbox Previews: Loads code within secure Linux containers where hot-reloading dev servers and browser preview ports are exposed via TLS tunnels.