Build apps like you never thought possible.

You dream up brilliant ideas. AI figures out how. On this site you can get your Harness Companion. Specialized automation for agentic work that handles everything: organizing branches, creating environments, and cleaning up when done.

How Harness Engineering looks like
PUSH
BRANCH
MERGE
TEST
DEPLOY
// example

How it looks like

You prompt. Claude writes the code. Your app is live. Automatically.

Your ideas...

... Created

/feature build a kanban board with drag-and-drop, task cards, dark theme, and deploy it
Ask Claude anything…
Opus 4.6 1M ∨
acme-saasdev
+
☁ kanban-project
kanban-abc.up.railway.app
TaskFlow
BoardTimelineSettings
RA
Sprint 14
Filter+ Task
To Do3
feature
Add user avatar upload to profile settings
JK
Apr 3
bug
Fix dropdown z-index on mobile nav
LS
Apr 2
design
Dark mode color token audit
MR
Apr 4
In Progress2
api
Implement drag-and-drop reordering endpoint
RA
Apr 1
feature
Real-time board sync via WebSockets
NK
Mar 30
Done2
api
Setup Prisma schema + seed data
RA
Mar 28
feature
Column layout + responsive grid
JK
Mar 27
deployed
// agentic automation

Your Harness Companion

Imagine you're building a web app. You ask Claude Code to add a dark mode feature. Claude writes the code and needs somewhere to put it. Without automation, you'd have to:

without harness: manual workflow
  • 1Manually create a branch for the feature
  • 2Manually review and merge the AI's code
  • 3Manually set up a test environment to preview
  • 4Manually create a pull request when ready
  • 5Manually tear down the environment after merging
  • 6Manually delete old branches to keep things tidy
with harness: fully automated
>Add dark mode to the app
Branch created & namedon push
Live URL generation, setting up DNSinstant
Preview environment scaffoldedauto
PR auto-created & mergedcommand
Environment deployed, URL sharedauto
Writing Release noteson merge
Environment & branches cleaned upon merge
New feature launched!
// getting started

How to get started?

01

Get your companion

Chat with Cuirass below. Tell him what you want to build and he’ll help you create your starter prompt.

Get your companion
02

Follow the wizard

You’ll be guided every step of the way. Creating your repo, tokens and environments. But first, get your companion below.

Get your companion
03

Build apps like you never thought possible.

With your CI/CD pipeline live and your companion by your side, every idea is one prompt away.

Get your companion
// get your companion

Get your companion

Describe your idea and we'll get you started. A draft starter prompt will be included so Claude builds your app directly from the first session.

Cuirassonline

Chat with Cuirass

Tell me what you want to build and I'll help you set it up

Or skip this and pick a variant manually

Manually pick your starting point

Picking manually is totally fine — your app's scope defines whether you need a deploy target or can work with a leaner companion. Slide to find yours.

drag to explore
Variant 02
~13 min setup

Web App

For landing pages, portfolios, dashboards, and apps. Each feature gets its own live URL, database, and file bucket. Use what you need; ignore what you don't.

Builds on Code Only, plus:

Live preview URL per feature you buildPostgreSQL database per environment (feature, dev, production)S3-compatible file bucket per environmentAutomatic environment creation on branch pushAutomatic cleanup on merge
// what is this

A new way to build software

Harness Engineering is an opinionated approach to building software. A single person, or a small team, directs AI agents through structured workflows called the harness. The harness ensures quality at speed, with minimal friction. Instead of writing every line of code by hand, you orchestrate intelligent agents that build, test, and deploy on your behalf.

traditional development
  • 1Speed is limited by how fast people can write code
  • 2Scaling means hiring more engineers
  • 3Context lives in people’s heads
  • 4Quality and speed are always in tension
harness engineering
  • Speed is limited by how fast you can review and iterate on ideas
  • Scaling means compounding, not linear growth
  • Context is encoded in the harness itself
  • Quality is built into the workflow, and speed follows naturally

The bottleneck is no longer writing code. It is deciding what to build. Harness Engineering shifts your team from execution to judgment, which is the one thing humans still do better than machines.

Read more about Harness Engineering
// HOW IT COMPARES

Not another AI platform.

Cursor, Replit, Lovable, and Vercel are platforms you use. Harness Companion is infrastructure you own. Here is what that means in practice.

Replit, Lovable
Shared workspace, one environment

Everyone shares the same staging environment. Test data collides between features. Coordinate manually or hope for the best.

Harness Companion
Isolated environment per branch

Every feature branch gets its own database, storage bucket, and preview URL. Automatically. Zero coordination.

/feature
Open SourceFull IsolationComposable TraitsAI-NativeComplete Lifecycle