Local-first AI coding agent for macOS

UnderStack Code

UnderStack Code plans, writes, tests and reviews code with AI models that run on your Mac. Every edit, command and deployment waits for your approval.

What you get

Perpetual licence — one payment, no subscription
All future updates of UnderStack Code included
Use on up to 2 Macs you own or control
Security updates until at least 31 December 2031

System requirements

macOS 14 Sonoma or later
Mac with Apple silicon (M1 or later)
16 GB unified memory minimum, 32 GB recommended
Free disk space for the AI models (up to about 30 GB)

Not included

The AI models (OpenAI gpt-oss, Google Gemma, Z-Image). The app downloads them for free from their publishers, under their own licences.
Optional online services (web search, Vercel previews) need your own account or key.

UnderStack Code is an AI system. Its output can be wrong — review code, commands and images before you rely on them. AI transparency notice

The first version is not yet notarized by Apple; the install guide shows how to open it the first time. Install guide

Coming soon

UnderStack Code is not on sale yet. Write to info@understack.dk if you want to hear when it launches.

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Total€50

incl. VAT · The VAT of your country is included; the invoice shows the amount.

I want the download to be available immediately. I expressly agree that UnderStack starts supplying the software before the 14-day withdrawal period ends, and I acknowledge that I lose my right of withdrawal once the download starts.I accept the Terms of Sale and the End-User Licence Agreement. I have read the Privacy Policy.

Payment is handled by Revolut. We never see your card details.