About a year ago I was switching tabs. Claude in one browser window. Gemini in another. OpenAI Codex in a third. Copy a question, paste it in, wait, copy the answer, switch tabs, paste it somewhere else. It was chaos — and I was doing it every single day.

Then I built QuadCode.

The idea was simple: what if all four agents lived side-by-side in a single terminal window, each in its own pane, all running at the same time? No more tab switching. No more losing context. No more picking one AI and hoping it's the right one for the job.

This post is about why that multi-agent approach genuinely changes how you code — and why the old "just pick your favorite AI" advice is starting to feel outdated.

The Problem With Picking Just One

Every developer I know has a favorite AI. Most of the time it's Claude. Sometimes it's Gemini. A few diehards still swear by Codex. But here's the thing — they're all right, and they're all wrong, depending on the task.

Claude is exceptional at understanding context across a large codebase. It reasons through architectural decisions in a way that feels almost like pairing with a senior engineer. But ask it to generate a dense block of boilerplate or scaffold out a repetitive CRUD API, and it'll occasionally overthink it.

Gemini CLI is fast. Genuinely fast. Google's 1M token context window is a real advantage when you're working with a sprawling monorepo. Its free tier is also the most generous of any agent right now — 1,000 requests per day with just a Google account login.

OpenAI Codex has tight GitHub integration and plays well with existing ChatGPT subscriptions. If you're already paying for ChatGPT Pro, Codex is essentially free.

And Aider? Aider is the OG. The open-source terminal coding agent that proved the whole concept was viable. It auto-commits with sensible messages, supports 100+ languages, and maps your entire codebase automatically. It's not flashy, but it gets things done.

Running just one of these means you're always leaving something on the table.

What "Running Them in Parallel" Actually Looks Like

When I open QuadCode, I get four terminal panes in a single window. Each pane runs a completely independent agent session. I can assign Claude to pane 1, Gemini to pane 2, Codex to pane 3, and Aider to pane 4 — or mix and match however I want.

Here's a real example of how my workflow looks:

All four are running simultaneously. Aider is crunching through its refactor while I'm actively directing Claude and Gemini on the new feature. By the time I loop back to pane 4, it's already committed three clean commits.

💡 The key insight: You're not asking the same question four times hoping for a better answer. You're running four different specialists on four different parts of the same problem — simultaneously.

Broadcast Mode Changes Everything

One of QuadCode's most underrated features is Broadcast Mode. Hit Cmd+B, type a command, and it sends instantly to all four panes at once.

The obvious use case is setup commands:

git pull
npm install
npm run test

But the real power is research prompts. When I'm starting a new feature, I'll sometimes broadcast the same high-level question to all four agents and then read through how each one approaches it. Claude tends to think in abstractions first. Gemini dives straight into code. Codex wants to know about the existing file structure. Aider just starts doing it.

Within 90 seconds, I have four different perspectives on the same problem. The best approach usually emerges pretty clearly from that.

The Agents Are Getting Better at Playing Together

Here's something I didn't expect: the agents start to feel like a team rather than competitors. Claude becomes your architect. Gemini becomes your fast typist. Codex becomes your git workflow manager. Aider becomes the background worker you trust with the tedious stuff.

Once you internalize which agent is good at which type of task, you stop thinking of them as alternatives and start thinking of them as collaborators. That mental shift is, I think, the real value of a tool like QuadCode — it makes multi-agent collaboration feel natural instead of chaotic.

The Setup Is Literally Two Commands

One of the things I cared most about when building QuadCode was making the setup trivially easy. You shouldn't need a PhD in terminal configuration to run four AI agents at once.

If you have Claude Code, Gemini CLI, Codex CLI, and Aider installed on your system, QuadCode detects them automatically. Each pane has a dropdown where you select the agent. Hit the ⚡ (Auto/Bypass) button and it passes the skip-prompts flag so the agent runs hands-free without waiting for you to confirm every action.

That's it. No config files. No environment wrestling. No YAML.

Why Now Is the Right Time for This

A year ago, running multiple AI coding agents simultaneously would have been painful. The tools weren't stable enough. The context windows were too small. The latency was too high to keep four sessions open at once.

That's all changed. Claude Sonnet 4 is fast. Gemini CLI's free tier is generous enough that keeping it open all day costs you nothing. Codex runs locally. Aider is rock solid.

The bottleneck isn't the AI anymore. The bottleneck is your interface — whether you're context-switching between tabs, or running everything in parallel in a tool built for it.

QuadCode is that tool. It's available for macOS (Apple Silicon and Intel) and Linux. There's a 7-day free trial — no credit card required. If you decide you like it, a lifetime license is $24.50 (launch price — increases April 15th). No subscription. No monthly bill. Pay once, use forever.

Try QuadCode Free for 7 Days

Run Claude, Gemini, Codex & Aider side-by-side. Mac & Linux. No credit card required.

⬇ Download Free Trial — macOS