Choose Cratis AI profiles

The Cratis AI marketplace plugins install the whole public skill set in one step. Many repositories need something narrower: a Kotlin Chronicle client that must not learn Arc conventions, an Arc-only backend with no event sourcing, a specifications library. Profiles are how you select that scope — and they work whether or not you use a marketplace.

Marketplace or profiles?

The two paths answer different questions and compose cleanly:

	Marketplace plugin	Profile subscription
Question it answers	“Give my assistant the Cratis skills”	“Give this repository exactly the skills its stack needs”
Scope	The whole public bundle (or the maintainer bundle)	The profiles you name — products, languages, and compositions
Selection granularity	One bundle	Per product, per language, per architecture
Versioning	Follows the Cratis/AI default branch you already read	Pinned to exact package versions; updates arrive as reviewed pull requests (designed — not published yet; today only @cratis/ai-fundamentals exists on npm)
Setup	One command per host	A committed .cratis/ai.json plus host packages
Good for	Trying Cratis AI, broad developer machines	Repositories with a fixed stack, teams that review AI changes

You can start with the marketplace and narrow later: the subscription path uses the same skills, so nothing you learn changes.

Choose the profile

Name the profile after the narrowest description of your repository:

Repository	Profile
Full Arc + Chronicle + React application	cratis/application
Arc backend without Chronicle	cratis/arc
Arc backend, C# only	cratis/arc/csharp
Arc backend in Kotlin	cratis/arc/kotlin
Chronicle client without Arc	cratis/chronicle
Chronicle client in Kotlin (Java rides the Kotlin JVM interop)	cratis/chronicle/kotlin
Chronicle client in TypeScript or Elixir	cratis/chronicle/typescript, cratis/chronicle/elixir
Application in a language Arc does not support yet	cratis/application/typescript, cratis/application/elixir (Chronicle-only until Arc supports the language)
Fundamentals library consumer	cratis/fundamentals
Specifications library	cratis/specifications/dotnet, cratis/specifications/typescript
Cratis framework or product repository (maintainers)	cratis/engineering

The language in cratis/<product>/<language> means the language you write that side of the stack in. Arc supports C# and Kotlin today; there is deliberately no cratis/arc/typescript.

The full map — every profile, what it composes, and its current status — lives in the profile reference in the Cratis/AI repository. The generated package and capability catalog shows each profile’s included skills and availability in plain language.

Subscribe in .cratis/ai.json

1. Create the subscription file in the consuming repository:

   {
     "schemaVersion": "1.0.0",
     "version": "1.0.0",
     "profiles": ["cratis/chronicle/kotlin"],
     "harnesses": ["claude", "codex", "copilot", "pi"],
     "updatePolicy": "reviewed-pull-request",
     "projectContext": ".cratis/PROJECT.md"
   }

2. Pin an exact version. latest, branches, and floating ranges are rejected. Rollback means restoring the previous exact version — never a floating one.

3. List your harnesses. The harnesses array names the hosts this repository expects the skills to reach.

4. Keep updatePolicy: reviewed-pull-request. Updates arrive as ordinary pull requests that change only the pin — you review them like any dependency.

5. Point projectContext at your project facts. The shared profiles never own your architecture, environment names, or commands; .cratis/PROJECT.md does. Keep credentials out of it.

The namespace derives the channel

Every profile id lives under cratis/. cratis/engineering alone derives the maintainer channel; every other cratis/* id derives the public channel, and the two can never appear in the same subscription.

Install the matching packages

A subscription names what the repository wants; the matching packages deliver it per host:

• Pi/npm — install the package for your profile at the exact pinned version:

  pi install -l npm:@cratis/ai-fundamentals@0.10.0

  Pi records the exact pin in .pi/settings.json; commit it after review.

• Marketplace hosts — the Claude Code, Codex, GitHub Copilot, and Cursor plugins resolve the same skills directly from the Cratis/AI repository, so a machine can run the marketplace plugin while the repository’s .cratis/ai.json documents the profile it should behave as.

No per-profile package beyond Fundamentals is published yet — the versioned flow is designed and tool-verified, but the first governed release has not been cut. Until it is, the marketplace plugin is the way to get the skills; the subscription still records the intended scope and starts receiving reviewed updates the moment the packages publish.

Update and roll back

Update and rollback are the same operation at different versions: change the exact version in .cratis/ai.json (and .pi/settings.json), review the pull request, and rerun your repository gates. Shared skill bodies never change under your feet, and removing a package never touches .cratis/PROJECT.md, AGENTS.md, or your local skills.

What not to do

• Do not copy .ai, .claude, .github, .agents, or .pi trees from another repository — that is the frozen propagation model the profiles replace.
• Do not mix public and engineering profiles in one subscription.
• Do not point a subscription at a floating version.

See Trust and distribution for why Cratis distributes skills this way, and Start using AI with Cratis for the marketplace install commands per host.