Frappe Custom App Syntax

Deterministic syntax reference for building Frappe custom apps — scaffolding, configuration, modules, patches, and fixtures.

Decision Tree

What do you need?
├─ Brand new app from scratch → bench new-app
├─ Extend existing ERPNext behavior → bench new-app + required_apps = ["frappe", "erpnext"]
├─ Install existing app from Git → bench get-app <url>
└─ Add functionality to an installed app
   ├─ New data model → Add module to modules.txt + create DocType
   ├─ New fields on existing DocType → Fixtures (Custom Field)
   ├─ Modify field properties → Fixtures (Property Setter)
   └─ Data migration → Patch in patches.txt

New app vs extend existing?
├─ Independent functionality → New app