Introducing December
December is an autonomous AI software engineer, built to help engineering teams plan, generate, test, and ship production-ready applications across cloud and terminal.
About December Agent
December pairs codebase intelligence with live, hardware-isolated sandboxes. Instead of offering speculative code completions, December acts as an end-to-end pair engineer: it inspects your directory structure, reads package manifests, executes commands, captures compiler diagnostics, and iterates autonomously until your tests pass.
Cloud & Terminal Synergy: Start tasks locally in your terminal with
@trydecember/cliand seamlessly transition into the web cloud sandbox atapp.trydecember.comusing the/handoffcommand.
Core Pillars
- Dual Surface Experience: Work inside your favorite local terminal environment, or migrate active sessions seamlessly to the cloud workspace.
- Deterministic Agent Loop: Uses an inspect-plan-execute-verify cycle. The agent inspects files, creates an implementation plan, makes changes, and executes test suites before concluding.
- Hardware-Isolated Cloud Previews: Spins up isolated virtual machines running genuine Linux runtimes for real-time web previews, API execution, and background worker testing.
- Git Checkpoints & Rollbacks: Every modification is versioned. Review diffs in real-time or roll back to any previous checkpoint with one click or terminal command.
- Bring Your Own Key (BYOK): Supports OpenAI, Anthropic (Claude 3.7 Sonnet), Google Gemini (Gemini 2.5 Flash/Pro), DeepSeek, OpenRouter, and local Ollama instances with zero token markup.
Quick Navigation
Documentation Directory
Explore guides, architecture deep-dives, CLI references, and integrations.
Core Concepts
Terminal-native execution with seamless cloud micro-VM handoff.
Deterministic inspect-plan-execute-verify cycle for safe edits.
Point-in-time versioning and rollback safety for local work trees.
Isolated Linux sandboxes with dev server provisioning and HMR.