inertia-rails-setup

Inertia Rails Project Setup

Detect stack, offer recommended deps, generate CLAUDE.md configuration.

Run once per project. Re-run when the stack changes.

NEVER:

• Run setup without inertia_rails gem in Gemfile — all skills assume it exists. If missing, tell the user to install it first.
• Overwrite existing ## Inertia Rails Stack in CLAUDE.md without reading it — the user may have manual customizations. Replace only the auto-generated block.
• Add @/ resolve aliases to vite.config.ts — vite-plugin-ruby already provides them. Only add to tsconfig.json.
• Recommend alba-inertia if the project uses jbuilder AND the user hasn't expressed interest in switching — suggest it, but don't push. You CAN still suggest it if the project has blueprinter (alba is a direct upgrade path).
• Generate CLAUDE.md blocks for skills the user doesn't have installed — saying "alba-inertia skill does NOT apply" is correct; saying "use alba-inertia" when the gem is absent is wrong.

Step 1: Detect Current Stack

Read Gemfile (NOT Gemfile.lock) and package.json and check for:

Look for	Means
inertia_rails gem	Inertia Rails installed (required)
@inertiajs/react in package.json	React frontend
@inertiajs/vue3 in package.json	Vue 3 frontend
@inertiajs/svelte in package.json	Svelte frontend
alba-inertia gem	Convention-based rendering active
alba + typelizer gems (no alba-inertia)	Alba serialization without convention rendering
pagy gem	Pagy pagination
kaminari gem	Kaminari pagination
rspec-rails gem	RSpec testing
js-routes gem	Typed frontend path helpers
devise gem	Devise authentication
pundit gem	Pundit authorization
action_policy gem	Action Policy authorization
components.json in root exists	shadcn installed (React: shadcn/ui, Vue: shadcn-vue, Svelte: shadcn-svelte)

Step 2: Recommend Missing Deps

Present detected stack, then offer deps that unlock skill features but aren't installed yet. Use AskUserQuestion with multiSelect for the recommendations.

Only recommend what's missing. Skip anything already detected in Step 1.

Dep	Type	Install command	What it unlocks
alba + typelizer + alba-inertia	gems	bundle add alba typelizer alba-inertia	Convention-based rendering, auto-generated TypeScript types from Ruby. Eliminates render inertia: { ... } boilerplate and manual TS interfaces. Unlocks alba-inertia skill.
js-routes	gem	bundle add js-routes	Typed path helpers (usersPath(), userPath(id)) in React — no more hardcoded URL strings.
pagy	gem	bundle add pagy	Lightweight pagination with Inertia-friendly metadata.
shadcn/ui (React)	npx	npx shadcn@latest init	Pre-built React components adapted for Inertia. Unlocks shadcn-inertia skill.
shadcn-vue (Vue)	npx	npx shadcn-vue@latest init	Pre-built Vue components adapted for Inertia. Unlocks shadcn-vue-inertia skill.
shadcn-svelte (Svelte)	npx	npx shadcn-svelte@latest init	Pre-built Svelte components (bits-ui) adapted for Inertia. Unlocks shadcn-svelte-inertia skill.

Do NOT recommend gems the user clearly chose alternatives for (e.g., don't suggest Pagy if Kaminari is present, you can still suggest alba if the project has jbuilder or blueprinter).

Step 3: Install Opted-In Deps

Post-install scaffolding per dep:

1. alba-inertia — also scaffold ApplicationResource:

   # app/resources/application_resource.rb
   class ApplicationResource
     include Alba::Resource
     helper Typelizer::DSL
     helper Alba::Inertia::Resource
     include Rails.application.routes.url_helpers
   end
   

   And add Typelizer initializer:

   # config/initializers/typelizer.rb
   Typelizer.configure do |config|
     config.output_dir = Rails.root.join("app/frontend/types/generated")
   end
   

2. js-routes — run rails generate js_routes if the generator exists
3. shadcn — framework-specific init:
   • React: npx shadcn@latest init
   • Vue: npx shadcn-vue@latest init
   • Svelte: npx shadcn-svelte@latest init After init, add @/ resolve aliases to tsconfig.json if not present

Step 4: Generate CLAUDE.md

Find or create CLAUDE.md in the project root. If ## Inertia Rails Stack exists, replace it (up to next ## or EOF). Otherwise, append.

MANDATORY — READ ENTIRE FILE before assembling the CLAUDE.md block: references/claude-md-templates.md (~90 lines) — all template blocks for each stack variant (serialization, UI, pagination, testing, routing, authorization). Pick one block per category based on the detected stack.

Do NOT load the templates file until Step 4 — Steps 1-3 determine which blocks to use.

Troubleshooting

Symptom	Cause	Fix
npx shadcn@latest init fails with "No framework detected"	Missing or misconfigured vite.config.ts	Ensure vite-plugin-ruby is configured and tailwindcss is in package.json before running init
Typelizer generates types in wrong directory	Missing or wrong output_dir in initializer	Add config/initializers/typelizer.rb with config.output_dir = Rails.root.join("app/frontend/types/generated")
@/ imports not resolving	Aliases added to vite.config.ts instead of tsconfig.json	vite-plugin-ruby handles Vite aliases — only tsconfig.json needs @/ paths for TypeScript
CLAUDE.md has conflicting instructions	Multiple ## Inertia Rails Stack sections	Delete duplicates — only one auto-generated block should exist
Skills reference alba-inertia but it's not installed	Setup wasn't run, or alba wasn't selected	Re-run setup; CLAUDE.md should say "alba-inertia skill does NOT apply" if gem is absent
js_routes:generate fails	js-routes gem installed but generator not yet run	Run rails generate js_routes first to create the config file, then rails js_routes:generate

Step 5: Summary

Tell the user:

1. What was installed
2. Which skills are relevant to their stack (and which to ignore)
3. Review ## Inertia Rails Stack in CLAUDE.md — it takes precedence over generic examples in individual skills