Boardflare Notebook Reference: Overview
This reference is the canonical guide for AI assistants and human developers working with Boardflare Python for Excel workbooks and the Boardflare Office add-in.
What is Boardflare?
Boardflare is an application-development platform for Microsoft Excel. It embeds a reactive Python environment powered by Marimo running in browser WebAssembly via Pyodide directly inside Excel’s shared runtime.
With Boardflare, a workbook becomes an interactive application: - Reactive Python Notebook: Write Python cells that automatically recalculate when upstream inputs change. - Worksheet Formulas: Publish computed data to Excel via =BF.OUTPUT("name") and callable Python functions via =BF.FUNCTION("name", arg1, ...). - Table Selection & Reactive Views: Read workbook inputs, track user selections in Excel tables, and compute dynamic derived views. - Durable Workbook Storage: Store the complete Marimo notebook source directly inside the .xlsx file (in the hidden _BOARDFLARE worksheet) so the application travels with the workbook without external file dependencies.
How AI Agents Should Use This Reference
When assisting users with a Boardflare workbook or modifying notebook code: 1. Identify the Task Layer: If answering questions about using the add-in or spreadsheet formula states, refer to the User Guide sections. If authoring or modifying code in _BOARDFLARE, refer to the Technical Authoring sections. 2. Respect the Boundaries: Never invent APIs or package imports. Boardflare runs in a strict zero-network Pyodide environment with a fixed set of pre-bundled packages. 3. Follow the Edit Loop: When modifying workbook code via Office.js or file editing, follow the deterministic handshake (increment H1, read H2) described in Workbook Editing. 4. Targeted Fixes: Inspect errors returned in the response JSON (H2) before making changes. Limit automated fix attempts to two iterations. 5. Verify Outputs: Verify that formulas resolve properly and do not show #BUSY!, #NAME?, #VALUE!, or #SPILL!.