What's Next

You built a working Library Management app: three DocTypes, a controller with
server-side validation, a form script, role permissions, a query report, and a
print format. From here you can go deeper into any part of the framework.

Build out the data model

• DocTypes Overview: the full data model, standard fields,
  and special DocType kinds.
• Fields: every field type and its key properties.
• Child Tables: rows embedded in a parent document, for
  example a list of fines on a transaction.
• Naming: all the ways the name primary key gets generated.
• Links and Actions: connect DocTypes and add document
  actions.

Write more server-side logic

• Controllers and Lifecycle: the complete list
  of lifecycle hooks, including submit, cancel and delete.
• Document API: reading and writing documents in
  code.
• Querying Data and the
  Query Builder: fetch and filter records.
• Whitelisted Methods: expose Python functions
  to the browser and the REST API.
• Background Jobs: run slow work off the request,
  for example sending overdue notices.
• Hooks: plug into other apps' DocTypes and framework
  events.

Do more on the client

• Form API: the full set of form events and frm
  methods.
• Dialog API and Controls:
  build custom dialogs and inputs.
• Server Calls: call your whitelisted methods from
  the browser.

Ship it

• REST API: read and write your data over HTTP.
• Testing: write tests for your controllers.
• Production Setup: deploy your app and site.

If you get stuck, the Frappe forum and the
source code are good places to look next.