amux vs Plandex

AI coding agent fleet vs. single-task coding engine — two different problems, two different tools. Updated July 2026.

If you want to run one complex, multi-file coding task carefully with staged review and rollback, Plandex is purpose-built for that. If you want to run 10-50 coding tasks in parallel overnight, check results from your phone in the morning, and manage agents alongside CRM and email — that's amux. Both are open source. They are not direct competitors; they solve different layers of the AI coding problem.

Quick comparison

What is Plandex?

Plandex is an open-source AI coding engine designed for long-running, complex coding tasks. You give it a goal — "refactor the auth module to use JWT instead of sessions" — and it breaks the task into steps, writes code incrementally into a protected sandbox, and shows you a staged diff before applying any changes. If something looks wrong, you can rewind.

Plandex's key strength is careful, reviewable, single-task execution. It supports multiple LLM backends (Anthropic Claude, OpenAI GPT-4, Google Gemini, local Llama models) and works entirely from the terminal. There is no web dashboard, no mobile app, and no concept of running multiple agents in parallel.

Plandex is well-suited for high-risk tasks where you want to review every file change before it lands: large refactors, schema migrations, security-sensitive code changes.

What is amux?

amux is an open-source control plane for running an AI engineering team from a single dashboard or your phone. It launches, monitors, and self-heals dozens of parallel Claude Code, Codex, or Gemini CLI sessions, with built-in kanban, notes, CRM, email, browser automation, and a scheduler. Self-healing, single Python file, zero external dependencies, MIT licensed.

amux's primary use case is parallel fleet management for overnight autonomous work. You queue up 10-20 tasks before bed, assign one agent per task, and wake up to pull requests. The self-healing watchdog handles context overflow, process crashes, stuck tool-approval prompts, and silent hangs — all without you being present.

Where Plandex beats amux

If you have a single, complex, high-risk coding job that touches many files and needs careful incremental review, Plandex is stronger. Its sandbox model means no change lands in your working tree until you approve it. The rewind feature lets you backtrack without hunting through git history. And because Plandex supports local models (Llama via Ollama), you can run it fully air-gapped at zero API cost.

• Staged diff review — see exactly what will change before it applies
• Built-in undo/rewind — step backward through task history
• Broad model support — Claude, GPT, Gemini, local models via API
• Sandbox isolation — changes stay in a protected context, not your working directory
• Interactive refinement — conversation-style mid-task corrections

Where amux beats Plandex

If your goal is to maximize throughput — running many tasks in parallel, overnight, without supervision — amux is the right tool. The gap widens when you need business-layer features (CRM, email, browser automation) that Plandex doesn't have, or when you want to manage your agents from your phone while away from your desk.

• Parallel fleet — 10-50 agents running simultaneously, not sequentially
• Self-healing watchdog — auto-compact on context overflow, restart on crash, replay last message
• YOLO mode (default) — auto-approves tool prompts so agents never block overnight
• Plan strip visibility — read Claude Code's native task list in real time from the dashboard
• Mobile-first — native iOS app + PWA for phone management, Plandex has neither
• Kanban board — shared SQLite board with atomic task claiming (no duplicated work)
• Built-in CRM — manage client relationships alongside your agent fleet
• Gmail API email — send updates from within amux
• Browser automation — Playwright-based with Inspect panel (console, network, errors)
• Scheduler — cron-style recurring tasks that trigger agent sessions

Execution model: parallel vs. sequential

This is the fundamental architectural difference. Plandex is sequential by design: it handles one task per session, builds up a coherent context for that task, and applies changes in a controlled sequence. This makes it excellent for tasks where order matters and you want fine-grained control at every step.

amux is parallel by design: each tmux session is an isolated Claude Code (or Codex/Gemini) process working on its own task in its own git worktree. Ten agents run ten tasks simultaneously. The shared kanban board uses SQLite compare-and-swap to prevent two agents from claiming the same task. A completed task opens a PR; a failed task stays in "todo" for the next run.

The practical consequence: in one night, amux can complete 10-50 tasks; Plandex completes 1-3 (sequentially, with review pauses). If throughput is the bottleneck, amux wins. If quality-of-review on a single critical task is the bottleneck, Plandex wins.

Overnight autonomy

Plandex is designed for interactive use — you guide it, review its diffs, and approve changes. Running it unattended overnight is technically possible but not its intended use: it will pause waiting for your review and there is no watchdog to restart it if something goes wrong.

amux is purpose-built for overnight autonomy. YOLO mode (now the default for new sessions in July 2026) auto-approves all tool-approval prompts. The watchdog monitors every session for idle hangs, context overflow, thinking-block corruption, and process crashes. If any occur, it handles them automatically. You can queue work at 11pm and wake up at 7am to 10 completed PRs.

From your phone — via the amux iOS app or PWA — you can check which tasks each agent completed, peek at the last 100 lines of any session's output, and send one-tap canned messages to redirect agents without touching your laptop.

Business tooling

Plandex is a coding tool only. amux goes beyond coding agents: it includes a contact CRM (add clients, log interactions, set follow-up reminders), Gmail API email integration (send updates from within amux, threading preserved), shared Playwright browser automation (run SaaS dashboard tasks via browser agents), a cron-style scheduler, and markdown notes. These features are particularly relevant for freelancers, solopreneurs, and startup founders who manage client relationships in the same tool they use to ship code.

Which should you use?

Choose Plandex if:

• You have one large, risky refactor that touches 20+ files
• You want staged diff review before any change lands
• You want built-in undo/rewind
• You need local model support (air-gapped, zero API cost)
• You are doing interactive, supervised coding — not overnight autonomous runs

Choose amux if:

• You want 10-50 parallel agents running overnight
• You need self-healing autonomy (no babysitting)
• You manage your agents from your phone
• You need CRM, email, browser automation, or a scheduler alongside your coding agents
• You want a shared kanban board with atomic task claiming for a team of agents
• You run Claude Code, Codex CLI, or Gemini CLI as your agent runtime

Use both if: You want Plandex for high-risk single jobs and amux for fleet-parallel feature work. They are complementary, not mutually exclusive.

Frequently asked questions

git clone https://github.com/mixpeek/amux && cd amux && ./install.sh
amux register myproject --dir ~/Dev/myproject --yolo
amux start myproject
amux serve  # → https://localhost:8822

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