Infinum AI Stack

A workflow, a set of skills, and a delivery platform — packaged together and installed per repo with one command — so specs, quality gates, and measurement live alongside the code.

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What's in the stack

#	Component	What it is
01	PSDD	Pragmatic Spec Driven Development — Infinum's 4-step workflow for shipping features with AI. Depth scales with the work.
02	Skills marketplace	Per-repo installable plugins — PRD authoring, security audits, UI validation, local PR review, and more. Install only what the project needs.
03	Caliber	Infinum's AI delivery platform. Define specs (PRD, brief, tech spec, plan) following PSDD, reviewed and approved in the portal; Assure every PR with code, security, and spec-conformance audits plus a human sign-off; Measure AI cost and delivery per project, team, and person. Agents connect through one MCP server — Claude Code via infinum/caliber-plugin. Talk to us to learn more.
04	Sandbox kits	Docker Sandboxes kits that give you an Infinum-ready claude sandbox in one command — plugins, house rules and team tooling preconfigured.

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Quick start

1. Align your AI coding setup

Run prompts/ai-engineering-setup.md with your AI coding agent of choice — Claude Code, Codex, Cursor, Gemini CLI, Copilot. The prompt is agent-agnostic. It checks what you already have and walks you through whatever's missing across four capabilities:

• A PRD creation skill
• A spec-driven development setup (Caliber, or your own equivalent)
• A local agentic PR-review skill
• A UI validation skill

Default to project-level setup. We prefer each repo to carry its own AI workflows so configuration ships with the code. User-level works too, but your improvements stay on your machine instead of traveling with the repo.

2. Use it on a real feature

The stack pays off on work with real complexity — a new screen, a meaningful refactor, business logic with edge cases. It's overkill for small bug fixes, copy tweaks, or anything you'd knock out in under an hour.

The full flow for a meaningful feature:

• Start from a PRD or a well-refined task ticket — capture what "done" means before writing any code
• Understand → design → plan → build, using Caliber's prd, brief, tech-spec, and plan commands or your equivalent spec-driven setup
• Iterate on the UI with the UI validation skill where applicable
• Run a local PR review before you push; with Caliber set up in the repository, the check runs on push and the PR gets its Caliber status

Optional: layer in cloud PR review (CodeRabbit) on top of the local pass for an additional automated check.

3. Stay current

The installer enables the stack-essentials plugin by default. It prints a banner at session start when infinum/ai has new commits on main since your last installer run — telling you a new version of the workspace installer is available and nudging you to re-run pnpm dlx github:infinum/ai. That's all it does; picking up the update is a manual re-run (do it yourself, or have an agent run it non-interactively — node bin/install.js --help lists the flags). Re-running is idempotent and reports exactly which rules changed (often "nothing" — see the plugin README for why). Plugin updates flow through the Claude Code marketplace's auto-update toggle separately.

To disable the update banner: set INFINUM_STACK_SKIP_UPDATE_CHECK=1 in your environment, or run /plugin disable stack-essentials.

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Glossary

Term	Meaning
The Stack	The packaged combination of workflow, skills, and delivery platform that Infinum engineers install per repo. Described in this document.
PSDD	Pragmatic Spec Driven Development — Infinum's 4-step workflow for building with AI. Full guide: psdd/README.md.
Skill	A focused, reusable instruction set installed as a plugin. Defined in a SKILL.md file. Each Infinum skill ships as its own plugin so engineers install only what they need.
Caliber	Infinum's AI delivery platform. Defines specs (Define), gates every pull request with audits and a human sign-off (Assure), and measures AI cost and delivery (Measure). Agents connect through one MCP server; Claude Code via infinum/caliber-plugin. More at caliber.infinum.com; talk to us to learn more.

For PSDD-specific terms (PRD/FRD, Technical brief, Ask mode, Plan mode, Build mode, Agent, Fresh agent, Context window) — see the PSDD glossary.

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License

This project is source-available, not open source. It is licensed under the Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0) — full text in LICENSE and at https://creativecommons.org/licenses/by-nc/4.0/. The license permits noncommercial use only and covers the entire repository, both its source code and its documentation.

What this means in practice

You are free to:

• read, use, copy, modify, and share this project;
• use it for personal, educational, research, and other noncommercial purposes;
• use it within charitable, educational, public-research, public-safety or health, environmental-protection, and government organizations,

as long as you give appropriate credit (attribution) and indicate any changes you made.

You may not use this project, or anything based on it, for any commercial purpose. A commercial purpose is, broadly, use primarily intended for or directed toward commercial advantage — including using this tooling or documentation to deliver services to your own clients or customers.

Commercial use

Infinum offers AI transformation as a service. If you want to use this tooling or documentation commercially — in your own products, in client work, or in your internal business operations — you need a separate commercial license from Infinum, which holds the copyright. To discuss commercial licensing, contact [email protected].

What's included, what's not

This repository contains the parts of our AI tooling and way-of-working documentation that we are comfortable sharing publicly. Client-specific material, credentials, internal-only processes, and other sensitive content have been removed and are kept in a separate private repository.

Trademarks

The name "Infinum", the Infinum logo, and other Infinum brand elements are trademarks of Infinum d.o.o. They are not licensed under CC BY-NC 4.0 or any other license in this repository, and nothing here grants you any right to use them.

No warranty

As stated in the license, this project is provided "as is", without warranties or conditions of any kind, to the fullest extent the law allows; Infinum will not be liable for any damages arising out of the license or the use of the project.

Contributions

Contributions are accepted by default only from the Infinum group (Infinum and its subsidiaries/affiliates); outside contributions are declined by default and require triage. See Contribution policy and licensing.