The Parallel AI Coding Setup That Changed How I Build Software

Most developers use AI coding assistants one conversation at a time. Ask a question, wait for the response, ask another question. It works, but it is slow.

I run 3-4 Claude Code terminals simultaneously. While one Claude builds a component, another writes tests, and a third handles the backend. This parallel workflow has fundamentally changed how I approach complex features.

#The Setup: VS Code Integrated Terminals

The key to this workflow is keeping everything in VS Code - not a separate terminal app like iTerm or Windows Terminal.

Why? Because your code stays visible while Claude works.

When Claude modifies a file, you see it immediately in the editor. You can verify changes in real-time, catch mistakes early, and maintain context on what each terminal is doing. With a separate terminal app, you are constantly switching windows, losing track of which Claude is doing what.

My typical layout:

┌─────────────────────────────────────┬────────────────────┐
│                                     │   Terminal 1       │
│                                     │   (Frontend)       │
│          Editor                     ├────────────────────┤
│          (Code visible)             │   Terminal 2       │
│                                     │   (Tests)          │
│                                     ├────────────────────┤
│                                     │   Terminal 3       │
│                                     │   (Backend)        │
└─────────────────────────────────────┴────────────────────┘

VS Code makes this easy. Right-click a terminal tab to rename it. Drag terminals to create split panes. Use `Ctrl+`` to toggle the terminal panel. The integration is seamless.

#Why Multiple Claudes?

Three reasons: speed, focus, and flexibility.

#Speed Through Parallelization

AI coding assistants are bottlenecked by thinking time. Claude needs to understand your codebase, plan an approach, and generate code. This takes seconds to minutes depending on complexity.

With one terminal, you wait. With three terminals, Terminal 2 and Terminal 3 are working while you review Terminal 1's output. You are always reviewing, never waiting.

A feature that takes 30 minutes sequentially might take 15 minutes in parallel - not because each task is faster, but because the tasks overlap.

#Focus Through Context Isolation

Each Claude instance maintains its own conversation context. This is a feature, not a limitation.

When a single Claude handles everything - frontend, backend, tests, documentation - its context becomes polluted. It starts mixing concerns. It suggests backend patterns in frontend code. It forgets earlier decisions.

Separate terminals mean separate contexts. The frontend Claude thinks only about components. The backend Claude focuses only on the API. Each stays sharp because each stays focused.

#Flexibility Through Dynamic Allocation

Not every task needs the same setup. I scale terminals based on complexity:

• Bug fix in one file: 1 terminal
• New feature touching frontend and backend: 2-3 terminals
• Major refactor across a monorepo: 3-4 terminals

The allocation changes mid-task too. Start with two terminals. Hit a testing bottleneck? Spin up a third dedicated to tests. Need to update docs? Add a fourth.

#Real Examples From My Workflow

#Single Frontend Repository: 3 Terminals

When building a new feature in a React or Angular app, I typically run three terminals:

Terminal 1 - Implementation: "Build the user settings page with form validation"

Terminal 2 - Tests: "Write unit tests for the settings form component"

Terminal 3 - Polish: "Add loading states and error handling to the settings page"

Terminal 1 builds the core functionality. While I review that, Terminal 2 starts writing tests against the expected behavior. Terminal 3 handles the details I would otherwise forget - loading spinners, error boundaries, edge cases.

#Monorepo: Split by Package

In a monorepo with separate frontend and backend packages:

Terminal 1 & 2 - Frontend: Two terminals for the UI. One for components, one for state management or API integration.

Terminal 3 - Backend: Handles API endpoints, database queries, validation.

Terminal 4 (optional) - Shared: For shared types, utilities, or configuration that both packages need.

The split depends on where the complexity lives. A UI-heavy feature might be 3 frontend + 1 backend. An API-heavy feature flips that ratio.

#Tips That Make This Work

#Use /clear Aggressively

Every new task starts with /clear. Do not let old context accumulate. Claude works better with fresh, focused context than with a long history of unrelated requests.

When I switch a terminal from "build the form" to "add form validation", I clear first. The new task gets Claude's full attention.

#Name Your Terminals

Right-click any terminal tab in VS Code and rename it. "Frontend", "Tests", "API" - whatever makes sense.

When you have four terminals running, unnamed tabs become chaos. Named tabs let you glance at the panel and know exactly where to look.

#Never Overlap Files

This is critical: do not let two Claude instances edit the same file simultaneously.

If Terminal 1 is modifying UserSettings.tsx and Terminal 2 tries to add tests that also modify that file, you will get conflicts. One overwrites the other. Changes get lost.

Divide work by file boundaries. Terminal 1 owns the component file. Terminal 2 owns the test file. No overlap, no conflicts.

#Use --resume and --continue

Claude Code remembers your sessions. Use claude --continue to pick up the most recent conversation. Use claude --resume to see a list of past sessions and choose one.

This means you can close VS Code, come back tomorrow, and resume exactly where each terminal left off.

#When to Scale Up or Down

The parallel workflow is not always necessary. Match your setup to the task:

Task Type	Terminals	Why
Quick bug fix	1	Simple scope, single file
Small feature	2	Implementation + tests
Medium feature	3	Frontend + backend + tests
Large refactor	3-4	Multiple packages or concerns
Full-stack feature	4	UI + API + DB + tests

Start small and scale up. You can always add another terminal. Removing one is harder - you lose that context.

#The Mental Model Shift

The hardest part is not the setup. It is changing how you think about AI coding.

Most developers treat Claude like a senior engineer sitting next to them. One conversation, one focus, one task at a time.

I treat Claude like a small team. Assign parallel tasks. Check in on progress. Merge the results. The AI handles the implementation; I handle the coordination.

This works because Claude Code is cheap. Running three instances costs about the same tokens as running one - you are just distributing those tokens across parallel work streams instead of one sequential stream.

#Summary

• Run Claude Code in VS Code integrated terminals, not a separate app
• Keep code visible to verify AI changes in real-time
• Use 2-4 terminals depending on task complexity
• Isolate context by concern: frontend, backend, tests, docs
• Use /clear liberally and never let terminals overlap on files
• Scale terminals up or down as the task demands

The parallel workflow will not make every task faster. But for complex features that touch multiple parts of your codebase, having multiple Claudes working simultaneously is a genuine productivity multiplier.

Stop waiting for one AI to finish. Put your terminals to work.