Petal Pro 4.0 — The AI-Ready Phoenix Boilerplate

Petal Pro 4.0 is out. Half our day is in Claude Code now — yours probably is too. v4 is the same Phoenix + LiveView SaaS starter you know, but with the AI tooling baked into the boilerplate itself. MCP server, recipe commands for the things people customise first, sub-agents that know your conventions. Plus the usual stack of new features.

What’s new

Admin MCP server

Point Claude Code at POST /api/mcp with a bearer token and you’ve got a working tool surface — search users, manage memberships, query stats — without leaving your editor. 10 actions ship out of the box. Adding a new one is one Jido.Action module.

AI admin chat (native Jido)

The in-app admin chat got rebuilt on Jido.Action so it shares the same tool registry as the MCP server. Add a tool once, get it in both places. LangChain and Tesla are gone. Everything’s on Req.

AI cost tracking

Every Claude/OpenAI/Gemini call gets logged with token counts, costs, and timing in ai_call_logs. Built as a Req plugin. No wrapper code in your app.

22 Claude Code recipes

Slash commands for the customisations everyone does first: /recipes:remove-billing, /recipes:add-magic-link-auth, /recipes:switch-to-single-tenant, /recipes:remove-orgs, and 18 more. Plus 5 sub-agents (schema-architect, elixir-reviewer, heex-reviewer, ui-ux-reviewer, test-runner) and a stack of scaffolding skills.

GDPR Your Data

A new /app/users/your-data page lets users export their full personal data as JSON and submit account deletion requests. Soft-delete + anonymisation cascade + Oban background processing. If you sell into the EU, that’s one less weekend you have to spend writing it.

Granular notification preferences

Per-type toggles for in-app vs email. Security-critical notifications are forced-on. Single dispatch entry point: Notifications.notify/3 — checks per-user preferences, fans out to the right channels.

In-app feedback

A built-in feedback widget at /app/feedback lets users submit bug reports and feature requests with category tags. You get a searchable admin dashboard to manage it all — no third-party tool needed.

Built-in changelog system

Ship your own changelog to your users, not just ours to you. Full admin CRUD with an Editor.js content editor, public pages with likes and social sharing, a promotional banner component, and email notifications when new entries are published.

New sidebar layout

The app shell got a full refresh. Collapsible sidebar with localStorage persistence, mobile-friendly sticky bar, and a live notification badge. The old top-nav header is gone.

DataTable overhaul

Declarative DataTableConfig, global search, filter chips, row selection, and bulk actions.

Org ownership model

New owner role (owner → admin → member), ownership transfer, self-service leave org, and invitation expiry with auto-purge.

Infrastructure

• Sentry error monitoring — set SENTRY_DSN and it just works
• Hammer rate limiting on auth endpoints
• Resend transactional email adapter
• Bunny.net file upload provider
• DB schema visualiser at /dev

• Dynamic OG image generation
• UUID v7 primary keys across the board
• Elixir 1.19+ / OTP 27
• HTTPoison/Tesla → Req across the board

Upgrading from v3

If you have an active membership, v4 is yours — log in and download.

The biggest item in the diff will be the Styler 1.11 reformat. Don’t panic — that’s expected. Read the upgrade guide before you cherry-pick.

Read the full changelog