arn-infra-define

Arness Infra Define

Generate infrastructure-as-code in the user's chosen IaC tool for their configured cloud provider(s). This is the central skill in the Arness Infra pipeline -- it reads the project's infrastructure configuration, resolves the application context, generates per-provider IaC code, validates it through a multi-level validation ladder, and produces an infrastructure architecture specification.

This skill is expertise-adaptive: beginner users receive platform-native configurations (e.g., fly.toml, vercel.json) instead of full IaC. Intermediate and expert users receive IaC in their chosen tool (OpenTofu, Pulumi, CDK, Bicep, kubectl/Helm).

If a triage implications brief exists (from arn-infra-triage), this skill uses it as the primary input for infrastructure decisions, skipping redundant codebase analysis.

Prerequisites

Read the ## Arness section from the project's CLAUDE.md. If no ## Arness section exists or Arness Infra fields are missing, inform the user: "Arness Infra is not configured for this project yet. Run /arn-infra-wizard to get started — it will set everything up automatically." Do not proceed without it.

Extract:

• Deferred -- if yes, inform the user that infrastructure is deferred and suggest running /arn-infra-assess first
• Experience level -- derived from user profile. Read ~/.arness/user-profile.yaml (or .claude/arness-profile.local.md if it exists — project override takes precedence). Apply the experience derivation mapping from ${CLAUDE_PLUGIN_ROOT}/skills/arn-infra-ensure-config/references/experience-derivation.md. If no profile exists, check for legacy Experience level in ## Arness as fallback.
• Providers -- which cloud providers to generate IaC for
• Providers config -- path to providers.md for per-provider scope and IaC tool overrides
• Default IaC tool -- the default IaC tool to use when no per-provider override exists
• Environments -- environment names (for environment-specific configurations)
• Environments config -- path to environments.md
• Tooling manifest -- path to tooling-manifest.json for tool availability checks
• Cost threshold -- monthly budget limit for cost gate warnings
• Validation ceiling -- maximum validation level before requiring explicit approval
• Infra plans directory -- from ## Arness config, for locating triage briefs (default: .arness/infra-plans)
• Infra specs directory -- from ## Arness config, for writing the INFRA spec (default: .arness/infra-specs)